Merge branch 'support-code' of github.umn.edu:umn-csci-4611-f21/shared-upstream

38 files changed, 2967 insertions, 1316 deletions

diff --git a/dev/MinGfx/src/gfxmath.cc b/dev/MinGfx/src/gfxmath.cc
index 20c9cc4..28cfedf 100644
--- a/dev/MinGfx/src/gfxmath.cc
+++ b/dev/MinGfx/src/gfxmath.cc
@@ -1,82 +1,137 @@
-/*

- Copyright (c) 2017,2018 Regents of the University of Minnesota.

- All Rights Reserved.

- See corresponding header file for details.

- */

-

-#include "gfxmath.h"

-

-#define _USE_MATH_DEFINES

-#include <math.h>

-#include <algorithm>

-

-#include "ray.h"

-

-

-namespace mingfx {

-    

-const float GfxMath::PI = 3.14159265359f;

-const float GfxMath::TWO_PI = 6.28318530718f;

-const float GfxMath::HALF_PI = 1.57079632679f;

-

-

-float GfxMath::Clamp(float x, float a, float b) {

-    return std::min(std::max(x, a), b);

-}    

-

-float GfxMath::ToRadians(float degrees) {

-    return degrees * GfxMath::PI / 180.0f;

-}

-

-float GfxMath::ToDegrees(float radians) {

-    return radians * 180.0f / GfxMath::PI;

-}

-

-Vector3 GfxMath::ToRadians(Vector3 degrees) {

-    return Vector3(ToRadians(degrees[0]), ToRadians(degrees[1]), ToRadians(degrees[2]));

-}

-

-Vector3 GfxMath::ToDegrees(Vector3 radians) {

-    return Vector3(ToDegrees(radians[0]), ToDegrees(radians[1]), ToDegrees(radians[2]));

-}

-    

-float GfxMath::Lerp(float a, float b, float alpha) {

-    return (1.0f-alpha)*a + alpha*b;

-}

-    

-int GfxMath::iLerp(int a, int b, float alpha) {

-    return (int)std::round((1.0f-alpha)*(float)a + alpha*(float)b);

-}

-    

-Point3 GfxMath::ScreenToNearPlane(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint) {

-    Matrix4 filmPtToWorld = (P*V).Inverse();

-    return filmPtToWorld * Point3(ndcPoint[0], ndcPoint[1], -1.0);

-}

-    

-    

-Point3 GfxMath::ScreenToWorld(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint, float zValue) {

-    Matrix4 filmPtToWorld = (P*V).Inverse();

-    float zneg1topos1 = zValue*2.0f - 1.0f;

-    return filmPtToWorld * Point3(ndcPoint[0], ndcPoint[1], zneg1topos1);

-}

-

-    

-Point3 GfxMath::ScreenToDepthPlane(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint, float planeDepth) {

-    Point3 pNear = ScreenToNearPlane(V, P, ndcPoint);

-    

-    Matrix4 camMat = V.Inverse();

-    Point3 eye = camMat.ColumnToPoint3(3);

-    Vector3 look = -camMat.ColumnToVector3(2);

-    

-    Ray r(eye, pNear - eye);

-    

-    Point3 p3D;

-    float t;

-    if (!r.IntersectPlane(eye + planeDepth*look, -look, &t, &p3D)) {

-        std::cerr << "filmplane2D_to_plane3D() error -- no intersection found!" << std::endl;

-    }

-    return p3D;

-}

-    

-    

-} // end namespace

+/*
+ Copyright (c) 2017,2018 Regents of the University of Minnesota.
+ All Rights Reserved.
+ See corresponding header file for details.
+ */
+
+#include "gfxmath.h"
+
+#define _USE_MATH_DEFINES
+#include <math.h>
+#include <algorithm>
+
+#include "ray.h"
+
+
+namespace mingfx {
+    
+const float GfxMath::PI = 3.14159265359f;
+const float GfxMath::TWO_PI = 6.28318530718f;
+const float GfxMath::HALF_PI = 1.57079632679f;
+
+float GfxMath::sin(float a) {
+#ifdef WIN32
+    return std::sinf(a);
+#else
+    return std::sin(a);
+#endif
+}
+
+float GfxMath::cos(float a) {
+#ifdef WIN32
+    return std::cosf(a);
+#else
+    return std::cos(a);
+#endif
+}
+
+float GfxMath::tan(float a) {
+#ifdef WIN32
+    return std::tanf(a);
+#else
+    return std::tan(a);
+#endif
+}
+
+float GfxMath::asin(float a) {
+#ifdef WIN32
+    return std::asinf(a);
+#else
+    return std::asin(a);
+#endif
+}
+
+float GfxMath::acos(float a) {
+#ifdef WIN32
+    return std::acosf(a);
+#else
+    return std::acos(a);
+#endif
+}
+
+float GfxMath::atan(float a) {
+#ifdef WIN32
+    return std::atanf(a);
+#else
+    return std::atan(a);
+#endif
+}
+
+float GfxMath::atan2(float a, float b) {
+#ifdef WIN32
+    return std::atan2f(a, b);
+#else
+    return std::atan2(a, b);
+#endif
+}
+
+float GfxMath::Clamp(float x, float a, float b) {
+    return std::min(std::max(x, a), b);
+}    
+
+float GfxMath::ToRadians(float degrees) {
+    return degrees * GfxMath::PI / 180.0f;
+}
+
+float GfxMath::ToDegrees(float radians) {
+    return radians * 180.0f / GfxMath::PI;
+}
+
+Vector3 GfxMath::ToRadians(Vector3 degrees) {
+    return Vector3(ToRadians(degrees[0]), ToRadians(degrees[1]), ToRadians(degrees[2]));
+}
+
+Vector3 GfxMath::ToDegrees(Vector3 radians) {
+    return Vector3(ToDegrees(radians[0]), ToDegrees(radians[1]), ToDegrees(radians[2]));
+}
+    
+float GfxMath::Lerp(float a, float b, float alpha) {
+    return (1.0f-alpha)*a + alpha*b;
+}
+    
+int GfxMath::iLerp(int a, int b, float alpha) {
+    return (int)std::round((1.0f-alpha)*(float)a + alpha*(float)b);
+}
+    
+Point3 GfxMath::ScreenToNearPlane(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint) {
+    Matrix4 filmPtToWorld = (P*V).Inverse();
+    return filmPtToWorld * Point3(ndcPoint[0], ndcPoint[1], -1.0);
+}
+    
+    
+Point3 GfxMath::ScreenToWorld(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint, float zValue) {
+    Matrix4 filmPtToWorld = (P*V).Inverse();
+    float zneg1topos1 = zValue*2.0f - 1.0f;
+    return filmPtToWorld * Point3(ndcPoint[0], ndcPoint[1], zneg1topos1);
+}
+
+    
+Point3 GfxMath::ScreenToDepthPlane(const Matrix4 &V, const Matrix4 &P, const Point2 &ndcPoint, float planeDepth) {
+    Point3 pNear = ScreenToNearPlane(V, P, ndcPoint);
+    
+    Matrix4 camMat = V.Inverse();
+    Point3 eye = camMat.ColumnToPoint3(3);
+    Vector3 look = -camMat.ColumnToVector3(2);
+    
+    Ray r(eye, pNear - eye);
+    
+    Point3 p3D;
+    float t;
+    if (!r.IntersectPlane(eye + planeDepth*look, -look, &t, &p3D)) {
+        std::cerr << "filmplane2D_to_plane3D() error -- no intersection found!" << std::endl;
+    }
+    return p3D;
+}
+    
+    
+} // end namespace
diff --git a/dev/MinGfx/src/gfxmath.h b/dev/MinGfx/src/gfxmath.h
index 8bb6c25..86c1061 100644
--- a/dev/MinGfx/src/gfxmath.h
+++ b/dev/MinGfx/src/gfxmath.h
@@ -1,81 +1,97 @@
-/*

- This file is part of the MinGfx Project.

- 

- Copyright (c) 2017,2018 Regents of the University of Minnesota.

- All Rights Reserved.

- 

- Original Author(s) of this File:

-	Dan Keefe, 2018, University of Minnesota

-	

- Author(s) of Significant Updates/Modifications to the File:

-	...

- */

-

-#ifndef SRC_GFXMATH_H_

-#define SRC_GFXMATH_H_

-

-#include "point2.h"

-#include "point3.h"

-#include "vector3.h"

-#include "matrix4.h"

-

-namespace mingfx {

-

-

-/** This class holds a variety of static math functions that are useful to have

- defined with creating graphics programs.

- */

-class GfxMath {

-public:

-

-    /// Returns a if x is less than a and b if x is greater than b.

-    static float Clamp(float x, float a, float b);

-        

-    static float ToRadians(float degrees);

-        

-    static float ToDegrees(float radians);

-    

-    static Vector3 ToRadians(Vector3 degrees);

-    

-    static Vector3 ToDegrees(Vector3 radians);

-    

-    static float Lerp(float a, float b, float alpha);

-

-    static int iLerp(int a, int b, float alpha);

-

-    /// Converts a 2D point on the filmplane represented in Normalized Device

-    /// Coorindates, which means (-1,1) for the top left corner of the screen and

-    /// (1,-1) for the bottom right corner, to a 3D point that lies on the camera's

-    /// near plane.  Useful for converting mouse coordinates into a 3D point.

-    /// Remember that this uses NORMALIZED device coordinates for the screenPt,

-    /// not pixels.  GraphicsApp and most other graphics engines report mouse move

-    /// events in pixels, so you need to convert these to normalized device coordinates

-    /// first.  If you are using GraphicsApp, you can do this with:

-    /// Point2 normPos = graphicsApp->pixels_to_normalized_coordinates(mousePos);

-    static Point3 ScreenToNearPlane(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt);

-

-    /// Similar to filmplane2D_to_nearplane3D() but here rather than using the

-    /// nearplane, you specify the depth of the plane to use as a distance away

-    /// from the camera's focal point.

-    static Point3 ScreenToDepthPlane(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt, float planeDepth);

-

-    /// Converts a 2D point on the filmplane represented in Normalized Device

-    /// Coorindates, which means (-1,1) for the top left corner of the screen and

-    /// (1,-1) for the bottom right corner, to a 3D point in the world.  The depth

-    /// buffer value under the pixel must be supplied. If you are using GraphicsApp,

-    /// you can use the mouse pos in pixels to get the required arguments like this:

-    /// Point2 normPos = graphicsApp->pixels_to_normalized_coordinates(mousePos);

-    /// float normZ = graphicsApp->z_value_at_pixel(mousePos);

-    static Point3 ScreenToWorld(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt, float normalizedZ);

-

-

-    static const float PI;

-    static const float TWO_PI;

-    static const float HALF_PI;

-};

-

-

-    

-} // end namespace

-

+/*
+ This file is part of the MinGfx Project.
+ 
+ Copyright (c) 2017,2018 Regents of the University of Minnesota.
+ All Rights Reserved.
+ 
+ Original Author(s) of this File:
+	Dan Keefe, 2018, University of Minnesota
+	
+ Author(s) of Significant Updates/Modifications to the File:
+	...
+ */
+
+#ifndef SRC_GFXMATH_H_
+#define SRC_GFXMATH_H_
+
+#include "point2.h"
+#include "point3.h"
+#include "vector3.h"
+#include "matrix4.h"
+
+namespace mingfx {
+
+
+/** This class holds a variety of static math functions that are useful to have
+ defined with creating graphics programs.
+ */
+class GfxMath {
+public:
+
+    /// MinGfx specific implementations of trigonometric functions included to
+    /// solve compilation issues between different platforms.
+    static float sin(float a);
+
+    static float cos(float a);
+
+    static float tan(float a);
+
+    static float asin(float a);
+
+    static float acos(float a);
+
+    static float atan(float a);
+
+    static float atan2(float a, float b);
+
+    /// Returns a if x is less than a and b if x is greater than b.
+    static float Clamp(float x, float a, float b);
+        
+    static float ToRadians(float degrees);
+        
+    static float ToDegrees(float radians);
+    
+    static Vector3 ToRadians(Vector3 degrees);
+    
+    static Vector3 ToDegrees(Vector3 radians);
+    
+    static float Lerp(float a, float b, float alpha);
+
+    static int iLerp(int a, int b, float alpha);
+
+    /// Converts a 2D point on the filmplane represented in Normalized Device
+    /// Coorindates, which means (-1,1) for the top left corner of the screen and
+    /// (1,-1) for the bottom right corner, to a 3D point that lies on the camera's
+    /// near plane.  Useful for converting mouse coordinates into a 3D point.
+    /// Remember that this uses NORMALIZED device coordinates for the screenPt,
+    /// not pixels.  GraphicsApp and most other graphics engines report mouse move
+    /// events in pixels, so you need to convert these to normalized device coordinates
+    /// first.  If you are using GraphicsApp, you can do this with:
+    /// Point2 normPos = graphicsApp->pixels_to_normalized_coordinates(mousePos);
+    static Point3 ScreenToNearPlane(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt);
+
+    /// Similar to filmplane2D_to_nearplane3D() but here rather than using the
+    /// nearplane, you specify the depth of the plane to use as a distance away
+    /// from the camera's focal point.
+    static Point3 ScreenToDepthPlane(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt, float planeDepth);
+
+    /// Converts a 2D point on the filmplane represented in Normalized Device
+    /// Coorindates, which means (-1,1) for the top left corner of the screen and
+    /// (1,-1) for the bottom right corner, to a 3D point in the world.  The depth
+    /// buffer value under the pixel must be supplied. If you are using GraphicsApp,
+    /// you can use the mouse pos in pixels to get the required arguments like this:
+    /// Point2 normPos = graphicsApp->pixels_to_normalized_coordinates(mousePos);
+    /// float normZ = graphicsApp->z_value_at_pixel(mousePos);
+    static Point3 ScreenToWorld(const Matrix4 &viewMatrix, const Matrix4 &projMatrix, const Point2 &normalizedScreenPt, float normalizedZ);
+
+
+    static const float PI;
+    static const float TWO_PI;
+    static const float HALF_PI;
+};
+
+
+    
+} // end namespace
+
 #endif
\ No newline at end of file
diff --git a/dev/MinGfx/src/quaternion.cc b/dev/MinGfx/src/quaternion.cc
index 7551c62..24830c8 100644
--- a/dev/MinGfx/src/quaternion.cc
+++ b/dev/MinGfx/src/quaternion.cc
@@ -1,260 +1,261 @@
-/*

-Copyright (c) 2017,2018 Regents of the University of Minnesota.

-All Rights Reserved.

-See corresponding header file for details.

-*/

-

-#define _USE_MATH_DEFINES

-#include "quaternion.h"

-

-#include "gfxmath.h"

-

-namespace mingfx {

-

-

-Quaternion::Quaternion() {

-    q[0] = 0.0;

-    q[1] = 0.0;

-    q[2] = 0.0;

-    q[3] = 1.0;

-}

-

-Quaternion::Quaternion(float qx, float qy, float qz, float qw) {

-    q[0] = qx;

-    q[1] = qy;

-    q[2] = qz;

-    q[3] = qw;

-}

-

-Quaternion::Quaternion(float *ptr) {

-    q[0] = ptr[0];

-    q[1] = ptr[1];

-    q[2] = ptr[2];

-    q[3] = ptr[3];

-}

-

-Quaternion::Quaternion(const Quaternion& other) {

-    q[0] = other[0];

-    q[1] = other[1];

-    q[2] = other[2];

-    q[3] = other[3];

-}

-

-Quaternion::~Quaternion() {

-}

-

-bool Quaternion::operator==(const Quaternion& other) const {

-    return (fabs(other[0] - q[0]) < MINGFX_MATH_EPSILON &&

-            fabs(other[1] - q[1]) < MINGFX_MATH_EPSILON &&

-            fabs(other[2] - q[2]) < MINGFX_MATH_EPSILON &&

-            fabs(other[3] - q[3]) < MINGFX_MATH_EPSILON);

-}

-

-bool Quaternion::operator!=(const Quaternion& other) const {

-    return (fabs(other[0] - q[0]) >= MINGFX_MATH_EPSILON ||

-            fabs(other[1] - q[1]) >= MINGFX_MATH_EPSILON ||

-            fabs(other[2] - q[2]) >= MINGFX_MATH_EPSILON ||

-            fabs(other[3] - q[3]) >= MINGFX_MATH_EPSILON);

-}

-

-Quaternion& Quaternion::operator=(const Quaternion& other) {

-    q[0] = other[0];

-    q[1] = other[1];

-    q[2] = other[2];

-    q[3] = other[3];

-    return *this;

-}

-

-float Quaternion::operator[](const int i) const {

-    if ((i>=0) && (i<=3)) {

-        return q[i];

-    }

-    else {

-        // this is an error!

-        return 0.0;

-    }

-}

-

-float& Quaternion::operator[](const int i) {

-    return q[i];

-}

-

-

-const float * Quaternion::value_ptr() const {

-    return q;

-}

-

-Quaternion Quaternion::Slerp(const Quaternion &other, float alpha) const {

-    // https://en.wikipedia.org/wiki/Slerp

-    

-    Quaternion v0 = *this;

-    Quaternion v1 = other;

-    

-    // Only unit quaternions are valid rotations.

-    // Normalize to avoid undefined behavior.

-    v0.Normalize();

-    v1.Normalize();

-    

-    // Compute the cosine of the angle between the two vectors.

-    float dot = v0.Dot(v1);

-    

-    // If the dot product is negative, the quaternions

-    // have opposite handed-ness and slerp won't take

-    // the shorter path. Fix by reversing one quaternion.

-    if (dot < 0.0f) {

-        v1 = -v1;

-        dot = -dot;

-    }

-    

-    const double DOT_THRESHOLD = 0.9995;

-    if (dot > DOT_THRESHOLD) {

-        // If the inputs are too close for comfort, linearly interpolate

-        // and normalize the result.

-        

-        Quaternion result = v0 + alpha*(v1 - v0);

-        result.Normalize();

-        return result;

-    }

-    

-    GfxMath::Clamp(dot, -1, 1);        // Robustness: Stay within domain of acos()

-    float theta_0 = acos(dot);        // theta_0 = angle between input vectors

-    float theta = theta_0 * alpha;    // theta = angle between v0 and result

-    

-    float s0 = cos(theta) - dot * sin(theta) / sin(theta_0);  // == sin(theta_0 - theta) / sin(theta_0)

-    float s1 = sin(theta) / sin(theta_0);

-    

-    return (s0 * v0) + (s1 * v1);

-}

-

-Quaternion Quaternion::Slerp(const Quaternion &a, const Quaternion &b, float alpha) {

-    return a.Slerp(b, alpha);

-}

-

-

-std::ostream & operator<< ( std::ostream &os, const Quaternion &q) {

-    return os << "<" << q[0] << ", " << q[1] << ", " << q[2] << ", " << q[3] << ")";

-}

-

-std::istream & operator>> ( std::istream &is, Quaternion &q) {

-    // format:  <qx, qy, qz, qw>

-    char dummy;

-    return is >> dummy >> q[0] >> dummy >> q[1] >> dummy >> q[2] >> dummy >> q[3] >> dummy;

-}

-

-

-float Quaternion::Dot(const Quaternion& other) const {

-    return q[0]*other[0] + q[1]*other[1] + q[2]*other[2] + q[3]*other[3];

-

-}

-

-float Quaternion::Length() const {

-    return sqrt(q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3]);

-}

-

-void Quaternion::Normalize() {

-    float sizeSq =  + q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3];

-    if (sizeSq < MINGFX_MATH_EPSILON) {

-        return; // do nothing to zero quats

-    }

-    float scaleFactor = (float)1.0/(float)sqrt(sizeSq);

-    q[0] *= scaleFactor;

-    q[1] *= scaleFactor;

-    q[2] *= scaleFactor;

-    q[3] *= scaleFactor;

-}

-

-Quaternion Quaternion::ToUnit() const {

-    Quaternion qtmp(*this);

-    qtmp.Normalize();

-    return qtmp;

-}

-

-/// Returns the conjugate of the quaternion.

-Quaternion Quaternion::Conjugate() const {

-    return Quaternion(-q[0], -q[1], -q[2], q[3]);

-}

-

-

-Quaternion Quaternion::FromAxisAngle(const Vector3 &axis, float angle) {

-    // [qx, qy, qz, qw] = [sin(a/2) * vx, sin(a/2)* vy, sin(a/2) * vz, cos(a/2)]

-    float x = sin(angle/2.0f) * axis[0];

-    float y = sin(angle/2.0f) * axis[1];

-    float z = sin(angle/2.0f) * axis[2];

-    float w = cos(angle/2.0f);

-    return Quaternion(x,y,z,w);

-}

-

-

-Quaternion Quaternion::FromEulerAnglesZYX(const Vector3 &angles) {

-    Quaternion rot_x = Quaternion::FromAxisAngle(Vector3::UnitX(), angles[0]);

-    Quaternion rot_y = Quaternion::FromAxisAngle(Vector3::UnitY(), angles[1]);

-    Quaternion rot_z = Quaternion::FromAxisAngle(Vector3::UnitZ(), angles[2]);

-    return rot_z * rot_y * rot_x;

-}

-

-Vector3 Quaternion::ToEulerAnglesZYX() const {

-    // https://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles

-

-    Vector3 angles;

-    

-    // roll (x-axis rotation)

-    float sinr = +2.0f * (w() * x() + y() * z());

-    float cosr = +1.0f - 2.0f * (x() * x() + y() * y());

-    angles[0] = std::atan2(sinr, cosr);

-    

-    // pitch (y-axis rotation)

-    float sinp = +2.0f * (w() * y() - z() * x());

-    if (std::fabs(sinp) >= 1.f)

-        angles[1] = std::copysign(GfxMath::HALF_PI, sinp); // use 90 degrees if out of range

-    else

-        angles[1] = std::asin(sinp);

-    

-    // yaw (z-axis rotation)

-    float siny = +2.0f * (w() * z() + x() * y());

-    float cosy = +1.0f - 2.0f * (y() * y() + z() * z());

-    angles[2] = std::atan2(siny, cosy);

-    

-    return angles;

-}

-

-

-Quaternion operator*(const Quaternion& q1, const Quaternion& q2) {

-    float real1 = q1[3];

-    Vector3 imag1 = Vector3(q1[0], q1[1], q1[2]);

-    

-    float real2 = q2[3];

-    Vector3 imag2 = Vector3(q2[0], q2[1], q2[2]);

-    

-    float real = real1*real2 - imag1.Dot(imag2);

-    Vector3 imag = real1*imag2 + real2*imag1 + imag1.Cross(imag2);

-    

-    return Quaternion(imag[0], imag[1], imag[2], real);

-}

-

-

-Quaternion operator/(const Quaternion& q, const float s) {

-    const float invS = 1.0f / s;

-    return Quaternion(q[0]*invS, q[1]*invS, q[2]*invS, q[3]*invS);

-}

-

-Quaternion operator*(const float s, const Quaternion& q) {

-    return Quaternion(q[0]*s, q[1]*s, q[2]*s, q[3]*s);

-}

-

-Quaternion operator*(const Quaternion& q, const float s) {

-    return Quaternion(q[0]*s, q[1]*s, q[2]*s, q[3]*s);

-}

-

-Quaternion operator-(const Quaternion& q) {

-    return Quaternion(-q[0], -q[1], -q[2], -q[3]);

-}

-

-Quaternion operator+(const Quaternion& q1, const Quaternion& q2) {

-    return Quaternion(q1[0] + q2[0], q1[1] + q2[1], q1[2] + q2[2], q1[3] + q2[3]);

-}

-

-Quaternion operator-(const Quaternion& q1, const Quaternion& q2) {

-    return Quaternion(q1[0] - q2[0], q1[1] - q2[1], q1[2] - q2[2], q1[3] - q2[3]);

-}

-    

-} // end namespace

+/*
+Copyright (c) 2017,2018 Regents of the University of Minnesota.
+All Rights Reserved.
+See corresponding header file for details.
+*/
+
+#define _USE_MATH_DEFINES
+#include "quaternion.h"
+
+#include "gfxmath.h"
+
+namespace mingfx {
+
+
+Quaternion::Quaternion() {
+    q[0] = 0.0;
+    q[1] = 0.0;
+    q[2] = 0.0;
+    q[3] = 1.0;
+}
+
+Quaternion::Quaternion(float qx, float qy, float qz, float qw) {
+    q[0] = qx;
+    q[1] = qy;
+    q[2] = qz;
+    q[3] = qw;
+}
+
+Quaternion::Quaternion(float *ptr) {
+    q[0] = ptr[0];
+    q[1] = ptr[1];
+    q[2] = ptr[2];
+    q[3] = ptr[3];
+}
+
+Quaternion::Quaternion(const Quaternion& other) {
+    q[0] = other[0];
+    q[1] = other[1];
+    q[2] = other[2];
+    q[3] = other[3];
+}
+
+Quaternion::~Quaternion() {
+}
+
+bool Quaternion::operator==(const Quaternion& other) const {
+    return (fabs(other[0] - q[0]) < MINGFX_MATH_EPSILON &&
+            fabs(other[1] - q[1]) < MINGFX_MATH_EPSILON &&
+            fabs(other[2] - q[2]) < MINGFX_MATH_EPSILON &&
+            fabs(other[3] - q[3]) < MINGFX_MATH_EPSILON);
+}
+
+bool Quaternion::operator!=(const Quaternion& other) const {
+    return (fabs(other[0] - q[0]) >= MINGFX_MATH_EPSILON ||
+            fabs(other[1] - q[1]) >= MINGFX_MATH_EPSILON ||
+            fabs(other[2] - q[2]) >= MINGFX_MATH_EPSILON ||
+            fabs(other[3] - q[3]) >= MINGFX_MATH_EPSILON);
+}
+
+Quaternion& Quaternion::operator=(const Quaternion& other) {
+    q[0] = other[0];
+    q[1] = other[1];
+    q[2] = other[2];
+    q[3] = other[3];
+    return *this;
+}
+
+float Quaternion::operator[](const int i) const {
+    if ((i>=0) && (i<=3)) {
+        return q[i];
+    }
+    else {
+        // this is an error!
+        return 0.0;
+    }
+}
+
+float& Quaternion::operator[](const int i) {
+    return q[i];
+}
+
+
+const float * Quaternion::value_ptr() const {
+    return q;
+}
+
+Quaternion Quaternion::Slerp(const Quaternion &other, float alpha) const {
+    // https://en.wikipedia.org/wiki/Slerp
+    
+    Quaternion v0 = *this;
+    Quaternion v1 = other;
+    
+    // Only unit quaternions are valid rotations.
+    // Normalize to avoid undefined behavior.
+    v0.Normalize();
+    v1.Normalize();
+    
+    // Compute the cosine of the angle between the two vectors.
+    float dot = v0.Dot(v1);
+    
+    // If the dot product is negative, the quaternions
+    // have opposite handed-ness and slerp won't take
+    // the shorter path. Fix by reversing one quaternion.
+    if (dot < 0.0f) {
+        v1 = -v1;
+        dot = -dot;
+    }
+    
+    const double DOT_THRESHOLD = 0.9995;
+    if (dot > DOT_THRESHOLD) {
+        // If the inputs are too close for comfort, linearly interpolate
+        // and normalize the result.
+        
+        Quaternion result = v0 + alpha*(v1 - v0);
+        result.Normalize();
+        return result;
+    }
+    
+    GfxMath::Clamp(dot, -1, 1);         // Robustness: Stay within domain of acos()
+    float theta_0 = GfxMath::acos(dot); // theta_0 = angle between input vectors
+    float theta = theta_0 * alpha;      // theta = angle between v0 and result
+    
+    float s0 = GfxMath::cos(theta) - dot
+             * GfxMath::sin(theta) / GfxMath::sin(theta_0);  // == sin(theta_0 - theta) / sin(theta_0)
+    float s1 = GfxMath::sin(theta) / GfxMath::sin(theta_0);
+    
+    return (s0 * v0) + (s1 * v1);
+}
+
+Quaternion Quaternion::Slerp(const Quaternion &a, const Quaternion &b, float alpha) {
+    return a.Slerp(b, alpha);
+}
+
+
+std::ostream & operator<< ( std::ostream &os, const Quaternion &q) {
+    return os << "<" << q[0] << ", " << q[1] << ", " << q[2] << ", " << q[3] << ")";
+}
+
+std::istream & operator>> ( std::istream &is, Quaternion &q) {
+    // format:  <qx, qy, qz, qw>
+    char dummy;
+    return is >> dummy >> q[0] >> dummy >> q[1] >> dummy >> q[2] >> dummy >> q[3] >> dummy;
+}
+
+
+float Quaternion::Dot(const Quaternion& other) const {
+    return q[0]*other[0] + q[1]*other[1] + q[2]*other[2] + q[3]*other[3];
+
+}
+
+float Quaternion::Length() const {
+    return sqrt(q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3]);
+}
+
+void Quaternion::Normalize() {
+    float sizeSq =  + q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3];
+    if (sizeSq < MINGFX_MATH_EPSILON) {
+        return; // do nothing to zero quats
+    }
+    float scaleFactor = (float)1.0/(float)sqrt(sizeSq);
+    q[0] *= scaleFactor;
+    q[1] *= scaleFactor;
+    q[2] *= scaleFactor;
+    q[3] *= scaleFactor;
+}
+
+Quaternion Quaternion::ToUnit() const {
+    Quaternion qtmp(*this);
+    qtmp.Normalize();
+    return qtmp;
+}
+
+/// Returns the conjugate of the quaternion.
+Quaternion Quaternion::Conjugate() const {
+    return Quaternion(-q[0], -q[1], -q[2], q[3]);
+}
+
+
+Quaternion Quaternion::FromAxisAngle(const Vector3 &axis, float angle) {
+    // [qx, qy, qz, qw] = [sin(a/2) * vx, sin(a/2)* vy, sin(a/2) * vz, cos(a/2)]
+    float x = GfxMath::sin(angle/2.0) * axis[0];
+    float y = GfxMath::sin(angle/2.0) * axis[1];
+    float z = GfxMath::sin(angle/2.0) * axis[2];
+    float w = GfxMath::cos(angle/2.0);
+    return Quaternion(x,y,z,w);
+}
+
+
+Quaternion Quaternion::FromEulerAnglesZYX(const Vector3 &angles) {
+    Quaternion rot_x = Quaternion::FromAxisAngle(Vector3::UnitX(), angles[0]);
+    Quaternion rot_y = Quaternion::FromAxisAngle(Vector3::UnitY(), angles[1]);
+    Quaternion rot_z = Quaternion::FromAxisAngle(Vector3::UnitZ(), angles[2]);
+    return rot_z * rot_y * rot_x;
+}
+
+Vector3 Quaternion::ToEulerAnglesZYX() const {
+    // https://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles
+
+    Vector3 angles;
+    
+    // roll (x-axis rotation)
+    float sinr = +2.0f * (w() * x() + y() * z());
+    float cosr = +1.0f - 2.0f * (x() * x() + y() * y());
+    angles[0] = std::atan2(sinr, cosr);
+    
+    // pitch (y-axis rotation)
+    float sinp = +2.0f * (w() * y() - z() * x());
+    if (std::fabs(sinp) >= 1.f)
+        angles[1] = std::copysign(GfxMath::HALF_PI, sinp); // use 90 degrees if out of range
+    else
+        angles[1] = std::asin(sinp);
+    
+    // yaw (z-axis rotation)
+    float siny = +2.0f * (w() * z() + x() * y());
+    float cosy = +1.0f - 2.0f * (y() * y() + z() * z());
+    angles[2] = std::atan2(siny, cosy);
+    
+    return angles;
+}
+
+
+Quaternion operator*(const Quaternion& q1, const Quaternion& q2) {
+    float real1 = q1[3];
+    Vector3 imag1 = Vector3(q1[0], q1[1], q1[2]);
+    
+    float real2 = q2[3];
+    Vector3 imag2 = Vector3(q2[0], q2[1], q2[2]);
+    
+    float real = real1*real2 - imag1.Dot(imag2);
+    Vector3 imag = real1*imag2 + real2*imag1 + imag1.Cross(imag2);
+    
+    return Quaternion(imag[0], imag[1], imag[2], real);
+}
+
+
+Quaternion operator/(const Quaternion& q, const float s) {
+    const float invS = 1.0f / s;
+    return Quaternion(q[0]*invS, q[1]*invS, q[2]*invS, q[3]*invS);
+}
+
+Quaternion operator*(const float s, const Quaternion& q) {
+    return Quaternion(q[0]*s, q[1]*s, q[2]*s, q[3]*s);
+}
+
+Quaternion operator*(const Quaternion& q, const float s) {
+    return Quaternion(q[0]*s, q[1]*s, q[2]*s, q[3]*s);
+}
+
+Quaternion operator-(const Quaternion& q) {
+    return Quaternion(-q[0], -q[1], -q[2], -q[3]);
+}
+
+Quaternion operator+(const Quaternion& q1, const Quaternion& q2) {
+    return Quaternion(q1[0] + q2[0], q1[1] + q2[1], q1[2] + q2[2], q1[3] + q2[3]);
+}
+
+Quaternion operator-(const Quaternion& q1, const Quaternion& q2) {
+    return Quaternion(q1[0] - q2[0], q1[1] - q2[1], q1[2] - q2[2], q1[3] - q2[3]);
+}
+    
+} // end namespace
diff --git a/dev/MinGfx/src/quick_shapes.cc b/dev/MinGfx/src/quick_shapes.cc
index dbd6c9e..01f187a 100644
--- a/dev/MinGfx/src/quick_shapes.cc
+++ b/dev/MinGfx/src/quick_shapes.cc
@@ -1,727 +1,733 @@
-/*

- Copyright (c) 2017,2018 Regents of the University of Minnesota.

- All Rights Reserved.

- See corresponding header file for details.

- */

-

-#include "quick_shapes.h"

-#include "platform.h"

-

-#include <cmath>

-#include <iostream>

-#include <string>

-

-

-namespace mingfx {

-    

-    

-    

-#define PI 3.14159265359f

-#define TWOPI 6.28318530718f

-    

-    

-    

-// Helper datastructure for building shapes algorithmically

-class Vertex {

-public:

-    Vertex(GLfloat xx, GLfloat yy, GLfloat zz, GLfloat nnx, GLfloat nny, GLfloat nnz) :

-    x(xx), y(yy), z(zz), nx(nnx), ny(nny), nz(nnz) {}

-    

-    GLfloat x;

-    GLfloat y;

-    GLfloat z;

-    GLfloat nx;

-    GLfloat ny;

-    GLfloat nz;

-};

-

-    

-    

-    

-QuickShapes::QuickShapes() {

-}

-

-QuickShapes::~QuickShapes() {

-}

-    

-    

-    

-    

-// ------------  CUBE  ------------

-

-

-void QuickShapes::initCube() {

-    GLfloat vertices[]  = {

-        1.0f, 1.0f, 1.0f,  -1.0f, 1.0f, 1.0f,  -1.0f,-1.0f, 1.0f,      // v0-v1-v2 (front)

-        -1.0f,-1.0f, 1.0f,   1.0f,-1.0f, 1.0f,   1.0f, 1.0f, 1.0f,      // v2-v3-v0

-        

-        1.0f, 1.0f, 1.0f,   1.0f,-1.0f, 1.0f,   1.0f,-1.0f,-1.0f,      // v0-v3-v4 (right)

-        1.0f,-1.0f,-1.0f,   1.0f, 1.0f,-1.0f,   1.0f, 1.0f, 1.0f,      // v4-v5-v0

-        

-        1.0f, 1.0f, 1.0f,   1.0f, 1.0f,-1.0f,  -1.0f, 1.0f,-1.0f,      // v0-v5-v6 (top)

-        -1.0f, 1.0f,-1.0f,  -1.0f, 1.0f, 1.0f,   1.0f, 1.0f, 1.0f,      // v6-v1-v0

-        

-        -1.0f, 1.0f, 1.0f,  -1.0f, 1.0f,-1.0f,  -1.0f,-1.0f,-1.0f,      // v1-v6-v7 (left)

-        -1.0f,-1.0f,-1.0f,  -1.0f,-1.0f, 1.0f,  -1.0f, 1.0f, 1.0f,      // v7-v2-v1.0

-        

-        -1.0f,-1.0f,-1.0f,   1.0f,-1.0f,-1.0f,   1.0f,-1.0f, 1.0f,      // v7-v4-v3 (bottom)

-        1.0f,-1.0f, 1.0f,  -1.0f,-1.0f, 1.0f,  -1.0f,-1.0f,-1.0f,      // v3-v2-v7

-        

-        1.0f,-1.0f,-1.0f,  -1.0f,-1.0f,-1.0f,  -1.0f, 1.0f,-1.0f,      // v4-v7-v6 (back)

-        -1.0f, 1.0f,-1.0f,   1.0f, 1.0f,-1.0f,   1.0f,-1.0f,-1.0f       // v6-v5-v4

-    };

-    

-    GLfloat normals[]   = {

-        0, 0, 1,   0, 0, 1,   0, 0, 1,      // v0-v1-v2 (front)

-        0, 0, 1,   0, 0, 1,   0, 0, 1,      // v2-v3-v0

-        

-        1, 0, 0,   1, 0, 0,   1, 0, 0,      // v0-v3-v4 (right)

-        1, 0, 0,   1, 0, 0,   1, 0, 0,      // v4-v5-v0

-        

-        0, 1, 0,   0, 1, 0,   0, 1, 0,      // v0-v5-v6 (top)

-        0, 1, 0,   0, 1, 0,   0, 1, 0,      // v6-v1-v0

-        

-        -1, 0, 0,  -1, 0, 0,  -1, 0, 0,     // v1-v6-v7 (left)

-        -1, 0, 0,  -1, 0, 0,  -1, 0, 0,     // v7-v2-v1

-        

-        0,-1, 0,   0,-1, 0,   0,-1, 0,      // v7-v4-v3 (bottom)

-        0,-1, 0,   0,-1, 0,   0,-1, 0,      // v3-v2-v7

-        

-        0, 0,-1,   0, 0,-1,   0, 0,-1,      // v4-v7-v6 (back)

-        0, 0,-1,   0, 0,-1,   0, 0,-1       // v6-v5-v4

-    };

-    

-    cubeMesh_.SetVertices(vertices, 36);

-    cubeMesh_.SetNormals(normals, 36);

-    cubeMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawCube(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (cubeMesh_.num_vertices() == 0) {

-        initCube();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &cubeMesh_, defaultMaterial_);

-}

-

-

-

-

-// ------------  SQUARE  ------------

-

-

-void QuickShapes::initSquare() {

-    GLfloat vertices[] = {

-        1.0f, 0.0f, 1.0f,   1.0f, 0.0f,-1.0f,  -1.0f, 0.0f,-1.0f,      // v0-v5-v6 (top)

-        -1.0f, 0.0f,-1.0f,  -1.0f, 0.0f, 1.0f,   1.0f, 0.0f, 1.0f      // v6-v1-v0

-    };

-    

-    GLfloat normals[] = {

-        0, 1, 0,   0, 1, 0,   0, 1, 0,

-        0, 1, 0,   0, 1, 0,   0, 1, 0

-    };

-    

-    GLfloat texcoords[] = {

-        1.0f, 1.0f,   1.0f, 0.0f,   0.0f, 0.0f,

-        0.0f, 0.0f,   0.0f, 1.0f,   1.0f, 1.0f

-    };

-    

-    squareMesh_.SetVertices(vertices, 6);

-    squareMesh_.SetNormals(normals, 6);

-    squareMesh_.SetTexCoords(0, texcoords, 6);

-    squareMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawSquare(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                  const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (squareMesh_.num_vertices() == 0) {

-        initSquare();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &squareMesh_, defaultMaterial_);

-}

-    

-

-void QuickShapes::DrawSquare(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                  const Matrix4 &projectionMatrix, const Color &color,

-                  const Texture2D &tex)

-{

-    if (squareMesh_.num_vertices() == 0) {

-        initSquare();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = tex;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &squareMesh_, defaultMaterial_);

-}

-    

-    

-    

-

-

-// ------------  CYLINDER  ------------

-

-

-void QuickShapes::initCyl() {

-    

-    std::vector<Vertex> verts;

-    

-    Vertex top(0,1,0, 0,1,0);

-    Vertex bot(0,-1,0, 0,-1,0);

-    

-    const int nslices = 20;

-    for (int s=1; s<nslices+1; s++) {

-        int slast = s - 1;

-        GLfloat xlast = std::cosf(-TWOPI * (float)slast / (float)nslices);

-        GLfloat zlast = std::sinf(-TWOPI * (float)slast/(float)nslices);

-        GLfloat xnew = std::cosf(-TWOPI * (float)(s)/(float)nslices);

-        GLfloat znew = std::sinf(-TWOPI * (float)(s)/(float)nslices);

-        

-        // one triangle on the top

-        verts.push_back(top);

-        verts.push_back(Vertex(xlast,1,zlast, 0,1,0));

-        verts.push_back(Vertex(xnew,1,znew, 0,1,0));

-        

-        // two triangles to create a rect on the side

-        verts.push_back(Vertex(xlast,1,zlast, xlast,0,zlast));

-        verts.push_back(Vertex(xlast,-1,zlast, xlast,0,zlast));

-        verts.push_back(Vertex(xnew,1,znew, xnew,0,znew));

-        

-        verts.push_back(Vertex(xnew,-1,znew, xnew,0,znew));

-        verts.push_back(Vertex(xnew,1,znew, xnew,0,znew));

-        verts.push_back(Vertex(xlast,-1,zlast, xlast,0,zlast));

-        

-        // one triangle on the bottom

-        verts.push_back(bot);

-        verts.push_back(Vertex(xnew,-1,znew, 0,-1,0));

-        verts.push_back(Vertex(xlast,-1,zlast, 0,-1,0));

-    }

-    

-    std::vector<Point3> vertices;

-    std::vector<Vector3> normals;

-    for (int i=0; i<verts.size(); i++) {

-        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));

-        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));

-    }    

-    cylMesh_.SetVertices(vertices);

-    cylMesh_.SetNormals(normals);

-    cylMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawCylinder(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                    const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (cylMesh_.num_vertices() == 0) {

-        initCyl();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &cylMesh_, defaultMaterial_);

-}

-

-

-

-

-// ------------  CONE  ------------

-

-

-void QuickShapes::initCone() {

-    

-    std::vector<Vertex> verts;

-    

-    Vertex top(0,1,0, 0,1,0);

-    Vertex bot(0,-1,0, 0,-1,0);

-    

-    const int nslices = 20;

-    for (int s=1; s<nslices+1; s++) {

-        int slast = s - 1;

-        GLfloat xlast = std::cosf(-TWOPI * (float)slast/(float)nslices);

-        GLfloat zlast = std::sinf(-TWOPI * (float)slast/(float)nslices);

-        GLfloat xnew = std::cosf(-TWOPI * (float)(s)/(float)nslices);

-        GLfloat znew = std::sinf(-TWOPI * (float)(s)/(float)nslices);

-        

-        // one triangle on the side

-        // normals are a bit more complex than for other shapes...

-        Vector3 nlast = Vector3(xlast, 2, zlast).ToUnit();

-        Vector3 nnew = Vector3(xnew, 2, znew).ToUnit();

-        Vector3 ntop = 0.5*(nlast + nnew);

-        

-        verts.push_back(Vertex(top.x, top.y, top.z, ntop[0], ntop[1], ntop[2]));

-        verts.push_back(Vertex(xlast,-1,zlast, nlast[0], nlast[1], nlast[2]));

-        verts.push_back(Vertex(xnew,-1,znew, nnew[0], nnew[1], nnew[2]));

-        

-        // one triangle on the bottom

-        verts.push_back(bot);

-        verts.push_back(Vertex(xnew,-1,znew, 0,-1,0));

-        verts.push_back(Vertex(xlast,-1,zlast, 0,-1,0));

-    }

-    

-    std::vector<Point3> vertices;

-    std::vector<Vector3> normals;

-    for (int i = 0; i < verts.size(); i++) {

-        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));

-        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));

-    }

-    

-    coneMesh_.SetVertices(vertices);

-    coneMesh_.SetNormals(normals);

-    coneMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawCone(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (coneMesh_.num_vertices() == 0) {

-        initCone();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &coneMesh_, defaultMaterial_);

-}

-

-

-

-

-

-// ------------  SPHERE  ------------

-

-

-void QuickShapes::initSph() {

-    

-    std::vector<Vertex> verts;

-    

-    Vertex top(0,1,0, 0,1,0);

-    Vertex bot(0,-1,0, 0,-1,0);

-    

-    const int nslices = 40;

-    const int nstacks = 40;

-    for (int s=1; s<nslices+1; s++) {

-        int slast = s - 1;

-        GLfloat xlast = std::cosf(-TWOPI * (float)slast/(float)nslices);

-        GLfloat zlast = std::sinf(-TWOPI * (float)slast/(float)nslices);

-        GLfloat xnew = std::cosf(-TWOPI * (float)(s)/(float)nslices);

-        GLfloat znew = std::sinf(-TWOPI * (float)(s)/(float)nslices);

-        

-        float stackstep = PI/(float)nstacks;

-        

-        // one triangle on the top

-        verts.push_back(top);

-        verts.push_back(Vertex(std::sinf(stackstep)*xlast,std::cosf(stackstep),std::sinf(stackstep)*zlast,

-                               std::sinf(stackstep)*xlast,std::cosf(stackstep),std::sinf(stackstep)*zlast));

-        verts.push_back(Vertex(std::sinf(stackstep)*xnew,std::cosf(stackstep),std::sinf(stackstep)*znew,

-                               std::sinf(stackstep)*xnew,std::cosf(stackstep),std::sinf(stackstep)*znew));

-        

-        for (int t=2; t<nstacks; t++) {

-            int tlast = t - 1;

-            GLfloat ylast = std::cosf(PI*(float)(tlast)/(float)nstacks);

-            GLfloat ynew = std::cosf(PI*(float)(t)/(float)nstacks);

-            

-            GLfloat rlast = std::sinf(PI * (float)(tlast)/(float)nstacks);

-            GLfloat rnew = std::sinf(PI * (float)(t)/(float)nstacks);

-            

-            // two triangles to create a rect on the side

-            verts.push_back(Vertex(rlast*xlast,ylast,rlast*zlast, rlast*xlast,ylast,rlast*zlast));

-            verts.push_back(Vertex(rnew*xlast,ynew,rnew*zlast, rnew*xlast,ynew,rnew*zlast));

-            verts.push_back(Vertex(rnew*xnew,ynew,rnew*znew, rnew*xnew,ynew,rnew*znew));

-            

-            verts.push_back(Vertex(rnew*xnew,ynew,rnew*znew, rnew*xnew,ynew,rnew*znew));

-            verts.push_back(Vertex(rlast*xnew,ylast,rlast*znew, rlast*xnew,ylast,rlast*znew));

-            verts.push_back(Vertex(rlast*xlast,ylast,rlast*zlast, rlast*xlast,ylast,rlast*zlast));

-        }

-        

-        // one triangle on the bottom

-        verts.push_back(bot);

-        verts.push_back(Vertex(std::sinf(stackstep)*xnew,std::cosf(PI-stackstep),std::sinf(stackstep)*znew,

-                               std::sinf(stackstep)*xnew,std::cosf(PI-stackstep),std::sinf(stackstep)*znew));

-        verts.push_back(Vertex(std::sinf(stackstep)*xlast,std::cosf(PI-stackstep),std::sinf(stackstep)*zlast,

-                               std::sinf(stackstep)*xlast,std::cosf(PI-stackstep),std::sinf(stackstep)*zlast));

-    }

-    

-    std::vector<Point3> vertices;

-    std::vector<Vector3> normals;

-    for (int i = 0; i < verts.size(); i++) {

-        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));

-        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));

-    }

-    sphereMesh_.SetVertices(vertices);

-    sphereMesh_.SetNormals(normals);

-    sphereMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawSphere(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                  const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (sphereMesh_.num_vertices() == 0) {

-        initSph();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &sphereMesh_, defaultMaterial_);

-}

-

-

-

-

-// ------------  BRUSH  ------------

-

-

-void QuickShapes::initBrush() {

-    

-    // Raw vertices -- points that make up the brush geometry

-    const GLfloat v[19][3] = {

-        { 0.5f,   0.0f,   0.0f},  // 0

-        {-0.5f,   0.0f,   0.0f},  // 1

-        

-        { 0.5f,   0.1f,   0.25f}, // 2

-        {-0.5f,   0.1f,   0.25f}, // 3

-        { 0.5f,   0.1f,   0.75f}, // 4

-        {-0.5f,   0.1f,   0.75f}, // 5

-        { 0.1f,   0.06f,  1.0f},  // 6

-        {-0.1f,   0.06f,  1.0f},  // 7

-        { 0.15f,  0.1f,   1.75f}, // 8

-        {-0.15f,  0.1f,   1.75f}, // 9

-        

-        { 0.0f,   0.0f,   1.85f}, // 10

-        

-        { 0.5f,  -0.1f,   0.25f}, // 11

-        {-0.5f,  -0.1f,   0.25f}, // 12

-        { 0.5f,  -0.1f,   0.75f}, // 13

-        {-0.5f,  -0.1f,   0.75f}, // 14

-        { 0.1f,  -0.06f,  1.0f},  // 15

-        {-0.1f,  -0.06f,  1.0f},  // 16

-        { 0.15f, -0.1f,   1.75f}, // 17

-        {-0.15f, -0.1f,   1.75f}  // 18

-    };

-    

-    

-    // Vertices arranged into triangles

-    const GLfloat verts[34][3][3] = {

-        // top

-        {{v[0][0], v[0][1], v[0][2]},  {v[1][0], v[1][1], v[1][2]},  {v[2][0], v[2][1], v[2][2]}},

-        {{v[1][0], v[1][1], v[1][2]},  {v[3][0], v[3][1], v[3][2]},  {v[2][0], v[2][1], v[2][2]}},

-        

-        {{v[2][0], v[2][1], v[2][2]},  {v[3][0], v[3][1], v[3][2]},  {v[4][0], v[4][1], v[4][2]}},

-        {{v[3][0], v[3][1], v[3][2]},  {v[5][0], v[5][1], v[5][2]},  {v[4][0], v[4][1], v[4][2]}},

-        

-        {{v[4][0], v[4][1], v[4][2]},  {v[5][0], v[5][1], v[5][2]},  {v[6][0], v[6][1], v[6][2]}},

-        {{v[5][0], v[5][1], v[5][2]},  {v[7][0], v[7][1], v[7][2]},  {v[6][0], v[6][1], v[6][2]}},

-        

-        {{v[6][0], v[6][1], v[6][2]},  {v[7][0], v[7][1], v[7][2]},  {v[8][0], v[8][1], v[8][2]}},

-        {{v[7][0], v[7][1], v[7][2]},  {v[9][0], v[9][1], v[9][2]},  {v[8][0], v[8][1], v[8][2]}},

-        

-        {{v[8][0], v[8][1], v[8][2]},  {v[9][0], v[9][1], v[9][2]},  {v[10][0], v[10][1], v[10][2]}},

-        

-        // bottom

-        {{v[0][0], v[0][1], v[0][2]},  {v[12][0], v[12][1], v[12][2]},  {v[1][0], v[1][1], v[1][2]}},

-        {{v[11][0], v[11][1], v[11][2]},  {v[12][0], v[12][1], v[12][2]},  {v[0][0], v[0][1], v[0][2]}},

-        

-        {{v[11][0], v[11][1], v[11][2]},  {v[14][0], v[14][1], v[14][2]},  {v[12][0], v[12][1], v[12][2]}},

-        {{v[13][0], v[13][1], v[13][2]},  {v[14][0], v[14][1], v[14][2]},  {v[11][0], v[11][1], v[11][2]}},

-        

-        {{v[13][0], v[13][1], v[13][2]},  {v[16][0], v[16][1], v[16][2]},  {v[14][0], v[14][1], v[14][2]}},

-        {{v[15][0], v[15][1], v[15][2]},  {v[16][0], v[16][1], v[16][2]},  {v[13][0], v[13][1], v[13][2]}},

-        

-        {{v[15][0], v[15][1], v[15][2]},  {v[18][0], v[18][1], v[18][2]},  {v[16][0], v[16][1], v[16][2]}},

-        {{v[17][0], v[17][1], v[17][2]},  {v[18][0], v[18][1], v[18][2]},  {v[15][0], v[15][1], v[15][2]}},

-        

-        {{v[18][0], v[18][1], v[18][2]},  {v[17][0], v[17][1], v[17][2]},  {v[10][0], v[10][1], v[10][2]}},

-        

-        // one side

-        {{v[11][0], v[11][1], v[11][2]},  {v[0][0], v[0][1], v[0][2]},  {v[2][0], v[2][1], v[2][2]}},

-        

-        {{v[11][0], v[11][1], v[11][2]},  {v[2][0], v[2][1], v[2][2]},  {v[4][0], v[4][1], v[4][2]}},

-        {{v[4][0], v[4][1], v[4][2]},  {v[13][0], v[13][1], v[13][2]},  {v[11][0], v[11][1], v[11][2]}},

-        

-        {{v[13][0], v[13][1], v[13][2]},  {v[4][0], v[4][1], v[4][2]},  {v[6][0], v[6][1], v[6][2]}},

-        {{v[6][0], v[6][1], v[6][2]},  {v[15][0], v[15][1], v[15][2]},  {v[13][0], v[13][1], v[13][2]}},

-        

-        {{v[15][0], v[15][1], v[15][2]},  {v[6][0], v[6][1], v[6][2]},  {v[8][0], v[8][1], v[8][2]}},

-        {{v[8][0], v[8][1], v[8][2]},  {v[17][0], v[17][1], v[17][2]},  {v[15][0], v[15][1], v[15][2]}},

-        

-        {{v[17][0], v[17][1], v[17][2]},  {v[8][0], v[8][1], v[8][2]},  {v[10][0], v[10][1], v[10][2]}},

-        

-        // other side

-        {{v[3][0], v[3][1], v[3][2]},  {v[1][0], v[1][1], v[1][2]},  {v[12][0], v[12][1], v[12][2]}},

-        

-        {{v[3][0], v[3][1], v[3][2]},  {v[12][0], v[12][1], v[12][2]},  {v[14][0], v[14][1], v[14][2]}},

-        {{v[14][0], v[14][1], v[14][2]},  {v[5][0], v[5][1], v[5][2]},  {v[3][0], v[3][1], v[3][2]}},

-        

-        {{v[5][0], v[5][1], v[5][2]},  {v[14][0], v[14][1], v[14][2]},  {v[16][0], v[16][1], v[16][2]}},

-        {{v[16][0], v[16][1], v[16][2]},  {v[7][0], v[7][1], v[7][2]},  {v[5][0], v[5][1], v[5][2]}},

-        

-        {{v[7][0], v[7][1], v[7][2]},  {v[16][0], v[16][1], v[16][2]},  {v[18][0], v[18][1], v[18][2]}},

-        {{v[18][0], v[18][1], v[18][2]},  {v[9][0], v[9][1], v[9][2]},  {v[7][0], v[7][1], v[7][2]}},

-        

-        {{v[9][0], v[9][1], v[9][2]},  {v[18][0], v[18][1], v[18][2]},  {v[10][0], v[10][1], v[10][2]}}

-        

-    };

-    

-    

-    // Normals defined so as to make each face of the brush a flat surface

-    const GLfloat norms[34][3][3] = {

-        // top

-        {{0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}},

-        {{0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}},

-        

-        {{0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}},

-        {{0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}},

-        

-        {{0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}},

-        {{0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}},

-        

-        {{0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}},

-        {{0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}},

-        

-        {{0.0f, 0.709f, 0.709f}, {0.0f, 0.709f, 0.709f}, {0.0f, 0.709f, 0.709f}},

-        

-        // bottom

-        {{0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}},

-        {{0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}},

-        

-        {{0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}},

-        {{0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}},

-        

-        {{0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}},

-        {{0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}},

-        

-        {{0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}},

-        {{0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}},

-        

-        {{0.0f, -0.709f, 0.709f}, {0.0f, -0.709f, 0.709f}, {0.0f, -0.709f, 0.709f}},

-        

-        // one side

-        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},

-        

-        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},

-        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},

-        

-        {{0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}},

-        {{0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}},

-        

-        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},

-        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},

-        

-        {{0.709f, 0.0f, 0.709f}, {0.709f, 0.0f, 0.709f}, {0.709f, 0.0f, 0.709f}},

-        

-        // other side

-        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},

-        

-        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},

-        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},

-        

-        {{-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}},

-        {{-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}},

-        

-        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},

-        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},

-        

-        {{-0.709f, 0.0f, 0.709f}, {-0.709f, 0.0f, 0.709f}, {-0.709f, 0.0f, 0.709f}}

-    };

-    

-    brushMesh_.SetVertices((float*)verts, 102);

-    brushMesh_.SetNormals((float*)norms, 102);

-    brushMesh_.UpdateGPUMemory();

-}

-

-

-void QuickShapes::DrawBrush(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,

-                 const Matrix4 &projectionMatrix, const Color &color)

-{

-    if (brushMesh_.num_vertices() == 0) {

-        initBrush();

-    }

-    defaultMaterial_.ambient_reflectance = color;

-    defaultMaterial_.diffuse_reflectance = color;

-    defaultMaterial_.surface_texture = emptyTex_;

-    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &brushMesh_, defaultMaterial_);

-}

-

-

-

-// ----------------

-

-

-void QuickShapes::DrawLineSegment(const Matrix4 &modelMatrix,

-                       const Matrix4 &viewMatrix,

-                       const Matrix4 &projectionMatrix,

-                       const Color &color,

-                       const Point3 &p1,

-                       const Point3 &p2,

-                       float radius)

-{

-    Matrix4 S = Matrix4::Scale(Vector3(radius, 0.5f*(p2-p1).Length(), radius));

-    Vector3 y = (p2-p1).ToUnit();

-    Vector3 z = Vector3(1,0,0).Cross(y).ToUnit();

-    if (z == Vector3(0,0,0)) {

-        z = Vector3(0,0,1).Cross(y).ToUnit();

-    }

-    Vector3 x = y.Cross(z);

-    Matrix4 R = Matrix4::FromRowMajorElements(

-        x[0], y[0], z[0], 0,

-        x[1], y[1], z[1], 0,

-        x[2], y[2], z[2], 0,

-        0,    0,    0, 1

-    );

-    Matrix4 T = Matrix4::Translation(0.5 * Vector3(p1[0]+p2[0], p1[1]+p2[1], p1[2]+p2[2]));

-    

-    Matrix4 M = T * R * S;

-    

-    DrawCylinder(modelMatrix * M, viewMatrix, projectionMatrix, color);

-}

-

-

-

-void QuickShapes::DrawLines(const Matrix4 &modelMatrix,

-                 const Matrix4 &viewMatrix,

-                 const Matrix4 &projectionMatrix,

-                 const Color &color,

-                 const std::vector<Point3> &points,

-                 LinesType ltype,

-                 float radius)

-{

-    if (ltype == LinesType::LINES) {

-        for (size_t i=0; i<points.size(); i+=2) {

-            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[i], points[i+1], radius);

-        }

-    }

-    else {

-        for (size_t i=0; i<points.size()-1; i++) {

-            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[i], points[i+1], radius);

-        }

-        if (ltype == LinesType::LINE_LOOP) {

-            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[points.size()-1], points[0], radius);

-        }

-    }

-}

-

-    

-    

-void QuickShapes::DrawArrow(const Matrix4 &modelMatrix,

-                 const Matrix4 &viewMatrix,

-                 const Matrix4 &projectionMatrix,

-                 const Color &color,

-                 Point3 p, Vector3 dir, float radius)

-{

-    float d = dir.Length() - 8.0f*radius;

-    DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, p, p + d*dir.ToUnit(), radius);

-    

-    Matrix4 S = Matrix4::Scale(Vector3(radius*3.0f, radius*4.0f, radius*3.0f));

-    Vector3 y = dir.ToUnit();

-    Vector3 z = Vector3(1,0,0).Cross(y).ToUnit();

-    if (z == Vector3(0,0,0)) {

-        z = Vector3(0,0,1).Cross(y).ToUnit();

-    }

-    Vector3 x = y.Cross(z);

-    Matrix4 R = Matrix4::FromRowMajorElements(

-                                              x[0], y[0], z[0], 0,

-                                              x[1], y[1], z[1], 0,

-                                              x[2], y[2], z[2], 0,

-                                              0,    0,    0, 1

-                                              );

-    Matrix4 T = Matrix4::Translation((p + d*dir.ToUnit()) - Point3::Origin());

-    

-    Matrix4 M = T * R * S * Matrix4::Translation(Vector3(0,1,0));

-    

-    DrawCone(modelMatrix * M, viewMatrix, projectionMatrix, color);

-}

-    

-    

-void QuickShapes::DrawAxes(const Matrix4 &modelMatrix,

-                const Matrix4 &viewMatrix,

-                const Matrix4 &projectionMatrix)

-{

-    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(1.0f, 0.6f, 0.6f), Point3::Origin(), Vector3::UnitX(), 0.02f);

-    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(0.6f, 1.0f, 0.6f), Point3::Origin(), Vector3::UnitY(), 0.02f);

-    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(0.6f, 0.6f, 1.0f), Point3::Origin(), Vector3::UnitZ(), 0.02f);

-

-}

-    

-    

-void QuickShapes::initFull() {

-    GLfloat vertices[] = {

-        -1, -1, 0,   1, -1, 0,  1, 1, 0,

-        -1, -1, 0,   1, 1, 0,   -1, 1, 0

-    };

-    

-    GLfloat normals[] = {

-        0, 0, 1,   0, 0, 1,   0, 0, 1,

-        0, 0, 1,   0, 0, 1,   0, 0, 1

-    };

-    

-    GLfloat texcoords[] = {

-        0.0f, 1.0f,   1.0f, 1.0f,   1.0f, 0.0f,

-        0.0f, 1.0f,   1.0f, 0.0f,   0.0f, 0.0f

-    };

-    

-    fullMesh_.SetVertices(vertices, 6);

-    fullMesh_.SetNormals(normals, 6);

-    fullMesh_.SetTexCoords(0, texcoords, 6);

-    fullMesh_.UpdateGPUMemory();

-}

-    

-

-void QuickShapes::DrawFullscreenTexture(const Color &color, const Texture2D &tex) {

-    if (fullMesh_.num_vertices() == 0) {

-        initFull();

-    }

-    DrawWithFullscreen(color, &fullMesh_, tex);

-}

-    

-    

-    

-    

-

-void QuickShapes::DrawWithFullscreen(const Color &color, Mesh *mesh, const Texture2D &tex) {

-    if (!fullscreenShader_.initialized()) {

-        fullscreenShader_.AddVertexShaderFromFile(Platform::FindMinGfxShaderFile("fullscreen.vert"));

-        fullscreenShader_.AddFragmentShaderFromFile(Platform::FindMinGfxShaderFile("fullscreen.frag"));

-        fullscreenShader_.LinkProgram();

-    }

-

-    glDisable(GL_DEPTH_TEST);

-    glDepthMask(GL_FALSE);

-    

-    // Activate the shader program

-    fullscreenShader_.UseProgram();

-    

-    // Pass uniforms and textures from C++ to the GPU Shader Program

-    fullscreenShader_.SetUniform("TintColor", color);

-    fullscreenShader_.BindTexture("SurfaceTexture", tex);

-    

-    // Draw the mesh using the shader program

-    mesh->Draw();

-    

-    // Deactivate the shader program

-    fullscreenShader_.StopProgram();

-    

-    glEnable(GL_DEPTH_TEST);

-    glDepthMask(GL_TRUE);

-}

-

-

-DefaultShader* QuickShapes::default_shader() {

-    return &defaultShader_;

-}

-    

-    

-DefaultShader::MaterialProperties* QuickShapes::material() {

-    return &defaultMaterial_;

-}

-

-    

-} // end namespace

+/*
+ Copyright (c) 2017,2018 Regents of the University of Minnesota.
+ All Rights Reserved.
+ See corresponding header file for details.
+ */
+
+#include "quick_shapes.h"
+#include "platform.h"
+
+#include <cmath>
+#include <iostream>
+#include <string>
+
+#include "gfxmath.h"
+
+namespace mingfx {
+    
+    
+    
+#define PI 3.14159265359f
+#define TWOPI 6.28318530718f
+    
+    
+    
+// Helper datastructure for building shapes algorithmically
+class Vertex {
+public:
+    Vertex(GLfloat xx, GLfloat yy, GLfloat zz, GLfloat nnx, GLfloat nny, GLfloat nnz) :
+    x(xx), y(yy), z(zz), nx(nnx), ny(nny), nz(nnz) {}
+    
+    GLfloat x;
+    GLfloat y;
+    GLfloat z;
+    GLfloat nx;
+    GLfloat ny;
+    GLfloat nz;
+};
+
+    
+    
+    
+QuickShapes::QuickShapes() {
+}
+
+QuickShapes::~QuickShapes() {
+}
+    
+    
+    
+    
+// ------------  CUBE  ------------
+
+
+void QuickShapes::initCube() {
+    GLfloat vertices[]  = {
+        1.0f, 1.0f, 1.0f,  -1.0f, 1.0f, 1.0f,  -1.0f,-1.0f, 1.0f,      // v0-v1-v2 (front)
+        -1.0f,-1.0f, 1.0f,   1.0f,-1.0f, 1.0f,   1.0f, 1.0f, 1.0f,      // v2-v3-v0
+        
+        1.0f, 1.0f, 1.0f,   1.0f,-1.0f, 1.0f,   1.0f,-1.0f,-1.0f,      // v0-v3-v4 (right)
+        1.0f,-1.0f,-1.0f,   1.0f, 1.0f,-1.0f,   1.0f, 1.0f, 1.0f,      // v4-v5-v0
+        
+        1.0f, 1.0f, 1.0f,   1.0f, 1.0f,-1.0f,  -1.0f, 1.0f,-1.0f,      // v0-v5-v6 (top)
+        -1.0f, 1.0f,-1.0f,  -1.0f, 1.0f, 1.0f,   1.0f, 1.0f, 1.0f,      // v6-v1-v0
+        
+        -1.0f, 1.0f, 1.0f,  -1.0f, 1.0f,-1.0f,  -1.0f,-1.0f,-1.0f,      // v1-v6-v7 (left)
+        -1.0f,-1.0f,-1.0f,  -1.0f,-1.0f, 1.0f,  -1.0f, 1.0f, 1.0f,      // v7-v2-v1.0
+        
+        -1.0f,-1.0f,-1.0f,   1.0f,-1.0f,-1.0f,   1.0f,-1.0f, 1.0f,      // v7-v4-v3 (bottom)
+        1.0f,-1.0f, 1.0f,  -1.0f,-1.0f, 1.0f,  -1.0f,-1.0f,-1.0f,      // v3-v2-v7
+        
+        1.0f,-1.0f,-1.0f,  -1.0f,-1.0f,-1.0f,  -1.0f, 1.0f,-1.0f,      // v4-v7-v6 (back)
+        -1.0f, 1.0f,-1.0f,   1.0f, 1.0f,-1.0f,   1.0f,-1.0f,-1.0f       // v6-v5-v4
+    };
+    
+    GLfloat normals[]   = {
+        0, 0, 1,   0, 0, 1,   0, 0, 1,      // v0-v1-v2 (front)
+        0, 0, 1,   0, 0, 1,   0, 0, 1,      // v2-v3-v0
+        
+        1, 0, 0,   1, 0, 0,   1, 0, 0,      // v0-v3-v4 (right)
+        1, 0, 0,   1, 0, 0,   1, 0, 0,      // v4-v5-v0
+        
+        0, 1, 0,   0, 1, 0,   0, 1, 0,      // v0-v5-v6 (top)
+        0, 1, 0,   0, 1, 0,   0, 1, 0,      // v6-v1-v0
+        
+        -1, 0, 0,  -1, 0, 0,  -1, 0, 0,     // v1-v6-v7 (left)
+        -1, 0, 0,  -1, 0, 0,  -1, 0, 0,     // v7-v2-v1
+        
+        0,-1, 0,   0,-1, 0,   0,-1, 0,      // v7-v4-v3 (bottom)
+        0,-1, 0,   0,-1, 0,   0,-1, 0,      // v3-v2-v7
+        
+        0, 0,-1,   0, 0,-1,   0, 0,-1,      // v4-v7-v6 (back)
+        0, 0,-1,   0, 0,-1,   0, 0,-1       // v6-v5-v4
+    };
+    
+    cubeMesh_.SetVertices(vertices, 36);
+    cubeMesh_.SetNormals(normals, 36);
+    cubeMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawCube(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (cubeMesh_.num_vertices() == 0) {
+        initCube();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &cubeMesh_, defaultMaterial_);
+}
+
+
+
+
+// ------------  SQUARE  ------------
+
+
+void QuickShapes::initSquare() {
+    GLfloat vertices[] = {
+        1.0f, 0.0f, 1.0f,   1.0f, 0.0f,-1.0f,  -1.0f, 0.0f,-1.0f,      // v0-v5-v6 (top)
+        -1.0f, 0.0f,-1.0f,  -1.0f, 0.0f, 1.0f,   1.0f, 0.0f, 1.0f      // v6-v1-v0
+    };
+    
+    GLfloat normals[] = {
+        0, 1, 0,   0, 1, 0,   0, 1, 0,
+        0, 1, 0,   0, 1, 0,   0, 1, 0
+    };
+    
+    GLfloat texcoords[] = {
+        1.0f, 1.0f,   1.0f, 0.0f,   0.0f, 0.0f,
+        0.0f, 0.0f,   0.0f, 1.0f,   1.0f, 1.0f
+    };
+    
+    squareMesh_.SetVertices(vertices, 6);
+    squareMesh_.SetNormals(normals, 6);
+    squareMesh_.SetTexCoords(0, texcoords, 6);
+    squareMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawSquare(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                  const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (squareMesh_.num_vertices() == 0) {
+        initSquare();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &squareMesh_, defaultMaterial_);
+}
+    
+
+void QuickShapes::DrawSquare(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                  const Matrix4 &projectionMatrix, const Color &color,
+                  const Texture2D &tex)
+{
+    if (squareMesh_.num_vertices() == 0) {
+        initSquare();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = tex;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &squareMesh_, defaultMaterial_);
+}
+    
+    
+    
+
+
+// ------------  CYLINDER  ------------
+
+
+void QuickShapes::initCyl() {
+    
+    std::vector<Vertex> verts;
+    
+    Vertex top(0,1,0, 0,1,0);
+    Vertex bot(0,-1,0, 0,-1,0);
+    
+    const int nslices = 20;
+    for (int s=1; s<nslices+1; s++) {
+        GLfloat xlast = GfxMath::cos(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat zlast = GfxMath::sin(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat xnew = GfxMath::cos(-TWOPI * (float)(s)/(float)nslices);
+        GLfloat znew = GfxMath::sin(-TWOPI * (float)(s)/(float)nslices);
+        
+        // one triangle on the top
+        verts.push_back(top);
+        verts.push_back(Vertex(xlast,1,zlast, 0,1,0));
+        verts.push_back(Vertex(xnew,1,znew, 0,1,0));
+        
+        // two triangles to create a rect on the side
+        verts.push_back(Vertex(xlast,1,zlast, xlast,0,zlast));
+        verts.push_back(Vertex(xlast,-1,zlast, xlast,0,zlast));
+        verts.push_back(Vertex(xnew,1,znew, xnew,0,znew));
+        
+        verts.push_back(Vertex(xnew,-1,znew, xnew,0,znew));
+        verts.push_back(Vertex(xnew,1,znew, xnew,0,znew));
+        verts.push_back(Vertex(xlast,-1,zlast, xlast,0,zlast));
+        
+        // one triangle on the bottom
+        verts.push_back(bot);
+        verts.push_back(Vertex(xnew,-1,znew, 0,-1,0));
+        verts.push_back(Vertex(xlast,-1,zlast, 0,-1,0));
+    }
+    
+    std::vector<Point3> vertices;
+    std::vector<Vector3> normals;
+    for (int i=0; i<verts.size(); i++) {
+        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));
+        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));
+    }    
+    cylMesh_.SetVertices(vertices);
+    cylMesh_.SetNormals(normals);
+    cylMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawCylinder(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                    const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (cylMesh_.num_vertices() == 0) {
+        initCyl();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &cylMesh_, defaultMaterial_);
+}
+
+
+
+
+// ------------  CONE  ------------
+
+
+void QuickShapes::initCone() {
+    
+    std::vector<Vertex> verts;
+    
+    Vertex top(0,1,0, 0,1,0);
+    Vertex bot(0,-1,0, 0,-1,0);
+    
+    const int nslices = 20;
+    for (int s=1; s<nslices+1; s++) {
+        GLfloat xlast = GfxMath::cos(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat zlast = GfxMath::sin(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat xnew = GfxMath::cos(-TWOPI * (float)(s)/(float)nslices);
+        GLfloat znew = GfxMath::sin(-TWOPI * (float)(s)/(float)nslices);
+        
+        // one triangle on the side
+        // normals are a bit more complex than for other shapes...
+        Vector3 nlast = Vector3(xlast, 2, zlast).ToUnit();
+        Vector3 nnew = Vector3(xnew, 2, znew).ToUnit();
+        Vector3 ntop = 0.5*(nlast + nnew);
+        
+        verts.push_back(Vertex(top.x, top.y, top.z, ntop[0], ntop[1], ntop[2]));
+        verts.push_back(Vertex(xlast,-1,zlast, nlast[0], nlast[1], nlast[2]));
+        verts.push_back(Vertex(xnew,-1,znew, nnew[0], nnew[1], nnew[2]));
+        
+        // one triangle on the bottom
+        verts.push_back(bot);
+        verts.push_back(Vertex(xnew,-1,znew, 0,-1,0));
+        verts.push_back(Vertex(xlast,-1,zlast, 0,-1,0));
+    }
+    
+    std::vector<Point3> vertices;
+    std::vector<Vector3> normals;
+    for (int i = 0; i < verts.size(); i++) {
+        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));
+        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));
+    }
+    
+    coneMesh_.SetVertices(vertices);
+    coneMesh_.SetNormals(normals);
+    coneMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawCone(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (coneMesh_.num_vertices() == 0) {
+        initCone();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &coneMesh_, defaultMaterial_);
+}
+
+
+
+
+
+// ------------  SPHERE  ------------
+
+
+void QuickShapes::initSph() {
+    
+    std::vector<Vertex> verts;
+    
+    Vertex top(0,1,0, 0,1,0);
+    Vertex bot(0,-1,0, 0,-1,0);
+    
+    const int nslices = 40;
+    const int nstacks = 40;
+    for (int s=1; s<nslices+1; s++) {
+        GLfloat xlast = GfxMath::cos(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat zlast = GfxMath::sin(-TWOPI * (float)(s-1)/(float)nslices);
+        GLfloat xnew = GfxMath::cos(-TWOPI * (float)(s)/(float)nslices);
+        GLfloat znew = GfxMath::sin(-TWOPI * (float)(s)/(float)nslices);
+        
+        float stackstep = PI/(float)nstacks;
+        
+        // one triangle on the top
+        verts.push_back(top);
+        verts.push_back(Vertex(GfxMath::sin(stackstep)*xlast,GfxMath::cos(stackstep),
+                               GfxMath::sin(stackstep)*zlast,
+                               GfxMath::sin(stackstep)*xlast,GfxMath::cos(stackstep),
+                               GfxMath::sin(stackstep)*zlast));
+        verts.push_back(Vertex(GfxMath::sin(stackstep)*xnew,GfxMath::cos(stackstep),
+                               GfxMath::sin(stackstep)*znew,
+                               GfxMath::sin(stackstep)*xnew,GfxMath::cos(stackstep),
+                               GfxMath::sin(stackstep)*znew));
+        
+        for (int t=2; t<nstacks; t++) {
+            GLfloat ylast = GfxMath::cos(PI*(float)(t-1)/(float)nstacks);
+            GLfloat ynew = GfxMath::cos(PI*(float)(t)/(float)nstacks);
+            
+            GLfloat rlast = GfxMath::sin(PI * (float)(t-1)/(float)nstacks);
+            GLfloat rnew = GfxMath::sin(PI * (float)(t)/(float)nstacks);
+            
+            // two triangles to create a rect on the side
+            verts.push_back(Vertex(rlast*xlast,ylast,rlast*zlast, rlast*xlast,ylast,rlast*zlast));
+            verts.push_back(Vertex(rnew*xlast,ynew,rnew*zlast, rnew*xlast,ynew,rnew*zlast));
+            verts.push_back(Vertex(rnew*xnew,ynew,rnew*znew, rnew*xnew,ynew,rnew*znew));
+            
+            verts.push_back(Vertex(rnew*xnew,ynew,rnew*znew, rnew*xnew,ynew,rnew*znew));
+            verts.push_back(Vertex(rlast*xnew,ylast,rlast*znew, rlast*xnew,ylast,rlast*znew));
+            verts.push_back(Vertex(rlast*xlast,ylast,rlast*zlast, rlast*xlast,ylast,rlast*zlast));
+        }
+        
+        // one triangle on the bottom
+        verts.push_back(bot);
+        verts.push_back(Vertex(GfxMath::sin(stackstep)*xnew,GfxMath::cos(PI-stackstep),
+                               GfxMath::sin(stackstep)*znew,
+                               GfxMath::sin(stackstep)*xnew,GfxMath::cos(PI-stackstep),
+                               GfxMath::sin(stackstep)*znew));
+        verts.push_back(Vertex(GfxMath::sin(stackstep)*xlast,GfxMath::cos(PI-stackstep),
+                               GfxMath::sin(stackstep)*zlast,
+                               GfxMath::sin(stackstep)*xlast,GfxMath::cos(PI-stackstep),
+                               GfxMath::sin(stackstep)*zlast));
+    }
+    
+    
+    std::vector<Point3> vertices;
+    std::vector<Vector3> normals;
+    for (int i = 0; i < verts.size(); i++) {
+        vertices.push_back(Point3(verts[i].x, verts[i].y, verts[i].z));
+        normals.push_back(Vector3(verts[i].nx, verts[i].ny, verts[i].nz));
+    }
+    sphereMesh_.SetVertices(vertices);
+    sphereMesh_.SetNormals(normals);
+    sphereMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawSphere(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                  const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (sphereMesh_.num_vertices() == 0) {
+        initSph();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &sphereMesh_, defaultMaterial_);
+}
+
+
+
+
+// ------------  BRUSH  ------------
+
+
+void QuickShapes::initBrush() {
+    
+    // Raw vertices -- points that make up the brush geometry
+    const GLfloat v[19][3] = {
+        { 0.5f,   0.0f,   0.0f},  // 0
+        {-0.5f,   0.0f,   0.0f},  // 1
+        
+        { 0.5f,   0.1f,   0.25f}, // 2
+        {-0.5f,   0.1f,   0.25f}, // 3
+        { 0.5f,   0.1f,   0.75f}, // 4
+        {-0.5f,   0.1f,   0.75f}, // 5
+        { 0.1f,   0.06f,  1.0f},  // 6
+        {-0.1f,   0.06f,  1.0f},  // 7
+        { 0.15f,  0.1f,   1.75f}, // 8
+        {-0.15f,  0.1f,   1.75f}, // 9
+        
+        { 0.0f,   0.0f,   1.85f}, // 10
+        
+        { 0.5f,  -0.1f,   0.25f}, // 11
+        {-0.5f,  -0.1f,   0.25f}, // 12
+        { 0.5f,  -0.1f,   0.75f}, // 13
+        {-0.5f,  -0.1f,   0.75f}, // 14
+        { 0.1f,  -0.06f,  1.0f},  // 15
+        {-0.1f,  -0.06f,  1.0f},  // 16
+        { 0.15f, -0.1f,   1.75f}, // 17
+        {-0.15f, -0.1f,   1.75f}  // 18
+    };
+    
+    
+    // Vertices arranged into triangles
+    const GLfloat verts[34][3][3] = {
+        // top
+        {{v[0][0], v[0][1], v[0][2]},  {v[1][0], v[1][1], v[1][2]},  {v[2][0], v[2][1], v[2][2]}},
+        {{v[1][0], v[1][1], v[1][2]},  {v[3][0], v[3][1], v[3][2]},  {v[2][0], v[2][1], v[2][2]}},
+        
+        {{v[2][0], v[2][1], v[2][2]},  {v[3][0], v[3][1], v[3][2]},  {v[4][0], v[4][1], v[4][2]}},
+        {{v[3][0], v[3][1], v[3][2]},  {v[5][0], v[5][1], v[5][2]},  {v[4][0], v[4][1], v[4][2]}},
+        
+        {{v[4][0], v[4][1], v[4][2]},  {v[5][0], v[5][1], v[5][2]},  {v[6][0], v[6][1], v[6][2]}},
+        {{v[5][0], v[5][1], v[5][2]},  {v[7][0], v[7][1], v[7][2]},  {v[6][0], v[6][1], v[6][2]}},
+        
+        {{v[6][0], v[6][1], v[6][2]},  {v[7][0], v[7][1], v[7][2]},  {v[8][0], v[8][1], v[8][2]}},
+        {{v[7][0], v[7][1], v[7][2]},  {v[9][0], v[9][1], v[9][2]},  {v[8][0], v[8][1], v[8][2]}},
+        
+        {{v[8][0], v[8][1], v[8][2]},  {v[9][0], v[9][1], v[9][2]},  {v[10][0], v[10][1], v[10][2]}},
+        
+        // bottom
+        {{v[0][0], v[0][1], v[0][2]},  {v[12][0], v[12][1], v[12][2]},  {v[1][0], v[1][1], v[1][2]}},
+        {{v[11][0], v[11][1], v[11][2]},  {v[12][0], v[12][1], v[12][2]},  {v[0][0], v[0][1], v[0][2]}},
+        
+        {{v[11][0], v[11][1], v[11][2]},  {v[14][0], v[14][1], v[14][2]},  {v[12][0], v[12][1], v[12][2]}},
+        {{v[13][0], v[13][1], v[13][2]},  {v[14][0], v[14][1], v[14][2]},  {v[11][0], v[11][1], v[11][2]}},
+        
+        {{v[13][0], v[13][1], v[13][2]},  {v[16][0], v[16][1], v[16][2]},  {v[14][0], v[14][1], v[14][2]}},
+        {{v[15][0], v[15][1], v[15][2]},  {v[16][0], v[16][1], v[16][2]},  {v[13][0], v[13][1], v[13][2]}},
+        
+        {{v[15][0], v[15][1], v[15][2]},  {v[18][0], v[18][1], v[18][2]},  {v[16][0], v[16][1], v[16][2]}},
+        {{v[17][0], v[17][1], v[17][2]},  {v[18][0], v[18][1], v[18][2]},  {v[15][0], v[15][1], v[15][2]}},
+        
+        {{v[18][0], v[18][1], v[18][2]},  {v[17][0], v[17][1], v[17][2]},  {v[10][0], v[10][1], v[10][2]}},
+        
+        // one side
+        {{v[11][0], v[11][1], v[11][2]},  {v[0][0], v[0][1], v[0][2]},  {v[2][0], v[2][1], v[2][2]}},
+        
+        {{v[11][0], v[11][1], v[11][2]},  {v[2][0], v[2][1], v[2][2]},  {v[4][0], v[4][1], v[4][2]}},
+        {{v[4][0], v[4][1], v[4][2]},  {v[13][0], v[13][1], v[13][2]},  {v[11][0], v[11][1], v[11][2]}},
+        
+        {{v[13][0], v[13][1], v[13][2]},  {v[4][0], v[4][1], v[4][2]},  {v[6][0], v[6][1], v[6][2]}},
+        {{v[6][0], v[6][1], v[6][2]},  {v[15][0], v[15][1], v[15][2]},  {v[13][0], v[13][1], v[13][2]}},
+        
+        {{v[15][0], v[15][1], v[15][2]},  {v[6][0], v[6][1], v[6][2]},  {v[8][0], v[8][1], v[8][2]}},
+        {{v[8][0], v[8][1], v[8][2]},  {v[17][0], v[17][1], v[17][2]},  {v[15][0], v[15][1], v[15][2]}},
+        
+        {{v[17][0], v[17][1], v[17][2]},  {v[8][0], v[8][1], v[8][2]},  {v[10][0], v[10][1], v[10][2]}},
+        
+        // other side
+        {{v[3][0], v[3][1], v[3][2]},  {v[1][0], v[1][1], v[1][2]},  {v[12][0], v[12][1], v[12][2]}},
+        
+        {{v[3][0], v[3][1], v[3][2]},  {v[12][0], v[12][1], v[12][2]},  {v[14][0], v[14][1], v[14][2]}},
+        {{v[14][0], v[14][1], v[14][2]},  {v[5][0], v[5][1], v[5][2]},  {v[3][0], v[3][1], v[3][2]}},
+        
+        {{v[5][0], v[5][1], v[5][2]},  {v[14][0], v[14][1], v[14][2]},  {v[16][0], v[16][1], v[16][2]}},
+        {{v[16][0], v[16][1], v[16][2]},  {v[7][0], v[7][1], v[7][2]},  {v[5][0], v[5][1], v[5][2]}},
+        
+        {{v[7][0], v[7][1], v[7][2]},  {v[16][0], v[16][1], v[16][2]},  {v[18][0], v[18][1], v[18][2]}},
+        {{v[18][0], v[18][1], v[18][2]},  {v[9][0], v[9][1], v[9][2]},  {v[7][0], v[7][1], v[7][2]}},
+        
+        {{v[9][0], v[9][1], v[9][2]},  {v[18][0], v[18][1], v[18][2]},  {v[10][0], v[10][1], v[10][2]}}
+        
+    };
+    
+    
+    // Normals defined so as to make each face of the brush a flat surface
+    const GLfloat norms[34][3][3] = {
+        // top
+        {{0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}},
+        {{0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}, {0.0f, 0.93f, -0.37f}},
+        
+        {{0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}},
+        {{0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}, {0.0f, 1.0f, 0.0f}},
+        
+        {{0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}},
+        {{0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}, {0.0f, 0.988f, 0.158f}},
+        
+        {{0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}},
+        {{0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}, {0.0f, 0.999f, -0.0533f}},
+        
+        {{0.0f, 0.709f, 0.709f}, {0.0f, 0.709f, 0.709f}, {0.0f, 0.709f, 0.709f}},
+        
+        // bottom
+        {{0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}},
+        {{0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}, {0.0f, -0.93f, -0.37f}},
+        
+        {{0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}},
+        {{0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}, {0.0f, -1.0f, 0.0f}},
+        
+        {{0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}},
+        {{0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}, {0.0f, -0.988f, 0.158f}},
+        
+        {{0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}},
+        {{0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}, {0.0f, -0.999f, -0.0533f}},
+        
+        {{0.0f, -0.709f, 0.709f}, {0.0f, -0.709f, 0.709f}, {0.0f, -0.709f, 0.709f}},
+        
+        // one side
+        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},
+        
+        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},
+        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},
+        
+        {{0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}},
+        {{0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}, {0.848f, 0.0f, 0.530f}},
+        
+        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},
+        {{1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}, {1.0f, 0.0f, 0.0f}},
+        
+        {{0.709f, 0.0f, 0.709f}, {0.709f, 0.0f, 0.709f}, {0.709f, 0.0f, 0.709f}},
+        
+        // other side
+        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},
+        
+        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},
+        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},
+        
+        {{-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}},
+        {{-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}, {-0.848f, 0.0f, 0.530f}},
+        
+        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},
+        {{-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}, {-1.0f, 0.0f, 0.0f}},
+        
+        {{-0.709f, 0.0f, 0.709f}, {-0.709f, 0.0f, 0.709f}, {-0.709f, 0.0f, 0.709f}}
+    };
+    
+    brushMesh_.SetVertices((float*)verts, 102);
+    brushMesh_.SetNormals((float*)norms, 102);
+    brushMesh_.UpdateGPUMemory();
+}
+
+
+void QuickShapes::DrawBrush(const Matrix4 &modelMatrix, const Matrix4 &viewMatrix,
+                 const Matrix4 &projectionMatrix, const Color &color)
+{
+    if (brushMesh_.num_vertices() == 0) {
+        initBrush();
+    }
+    defaultMaterial_.ambient_reflectance = color;
+    defaultMaterial_.diffuse_reflectance = color;
+    defaultMaterial_.surface_texture = emptyTex_;
+    defaultShader_.Draw(modelMatrix, viewMatrix, projectionMatrix, &brushMesh_, defaultMaterial_);
+}
+
+
+
+// ----------------
+
+
+void QuickShapes::DrawLineSegment(const Matrix4 &modelMatrix,
+                       const Matrix4 &viewMatrix,
+                       const Matrix4 &projectionMatrix,
+                       const Color &color,
+                       const Point3 &p1,
+                       const Point3 &p2,
+                       float radius)
+{
+    Matrix4 S = Matrix4::Scale(Vector3(radius, 0.5f*(p2-p1).Length(), radius));
+    Vector3 y = (p2-p1).ToUnit();
+    Vector3 z = Vector3(1,0,0).Cross(y).ToUnit();
+    if (z == Vector3(0,0,0)) {
+        z = Vector3(0,0,1).Cross(y).ToUnit();
+    }
+    Vector3 x = y.Cross(z);
+    Matrix4 R = Matrix4::FromRowMajorElements(
+        x[0], y[0], z[0], 0,
+        x[1], y[1], z[1], 0,
+        x[2], y[2], z[2], 0,
+        0,    0,    0, 1
+    );
+    Matrix4 T = Matrix4::Translation(0.5 * Vector3(p1[0]+p2[0], p1[1]+p2[1], p1[2]+p2[2]));
+    
+    Matrix4 M = T * R * S;
+    
+    DrawCylinder(modelMatrix * M, viewMatrix, projectionMatrix, color);
+}
+
+
+
+void QuickShapes::DrawLines(const Matrix4 &modelMatrix,
+                 const Matrix4 &viewMatrix,
+                 const Matrix4 &projectionMatrix,
+                 const Color &color,
+                 const std::vector<Point3> &points,
+                 LinesType ltype,
+                 float radius)
+{
+    if (ltype == LinesType::LINES) {
+        for (size_t i=0; i<points.size(); i+=2) {
+            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[i], points[i+1], radius);
+        }
+    }
+    else {
+        for (size_t i=0; i<points.size()-1; i++) {
+            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[i], points[i+1], radius);
+        }
+        if (ltype == LinesType::LINE_LOOP) {
+            DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, points[points.size()-1], points[0], radius);
+        }
+    }
+}
+
+    
+    
+void QuickShapes::DrawArrow(const Matrix4 &modelMatrix,
+                 const Matrix4 &viewMatrix,
+                 const Matrix4 &projectionMatrix,
+                 const Color &color,
+                 Point3 p, Vector3 dir, float radius)
+{
+    float d = dir.Length() - 8.0f*radius;
+    DrawLineSegment(modelMatrix, viewMatrix, projectionMatrix, color, p, p + d*dir.ToUnit(), radius);
+    
+    Matrix4 S = Matrix4::Scale(Vector3(radius*3.0f, radius*4.0f, radius*3.0f));
+    Vector3 y = dir.ToUnit();
+    Vector3 z = Vector3(1,0,0).Cross(y).ToUnit();
+    if (z == Vector3(0,0,0)) {
+        z = Vector3(0,0,1).Cross(y).ToUnit();
+    }
+    Vector3 x = y.Cross(z);
+    Matrix4 R = Matrix4::FromRowMajorElements(
+                                              x[0], y[0], z[0], 0,
+                                              x[1], y[1], z[1], 0,
+                                              x[2], y[2], z[2], 0,
+                                              0,    0,    0, 1
+                                              );
+    Matrix4 T = Matrix4::Translation((p + d*dir.ToUnit()) - Point3::Origin());
+    
+    Matrix4 M = T * R * S * Matrix4::Translation(Vector3(0,1,0));
+    
+    DrawCone(modelMatrix * M, viewMatrix, projectionMatrix, color);
+}
+    
+    
+void QuickShapes::DrawAxes(const Matrix4 &modelMatrix,
+                const Matrix4 &viewMatrix,
+                const Matrix4 &projectionMatrix)
+{
+    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(1.0f, 0.6f, 0.6f), Point3::Origin(), Vector3::UnitX(), 0.02f);
+    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(0.6f, 1.0f, 0.6f), Point3::Origin(), Vector3::UnitY(), 0.02f);
+    DrawArrow(modelMatrix, viewMatrix, projectionMatrix, Color(0.6f, 0.6f, 1.0f), Point3::Origin(), Vector3::UnitZ(), 0.02f);
+
+}
+    
+    
+void QuickShapes::initFull() {
+    GLfloat vertices[] = {
+        -1, -1, 0,   1, -1, 0,  1, 1, 0,
+        -1, -1, 0,   1, 1, 0,   -1, 1, 0
+    };
+    
+    GLfloat normals[] = {
+        0, 0, 1,   0, 0, 1,   0, 0, 1,
+        0, 0, 1,   0, 0, 1,   0, 0, 1
+    };
+    
+    GLfloat texcoords[] = {
+        0.0f, 1.0f,   1.0f, 1.0f,   1.0f, 0.0f,
+        0.0f, 1.0f,   1.0f, 0.0f,   0.0f, 0.0f
+    };
+    
+    fullMesh_.SetVertices(vertices, 6);
+    fullMesh_.SetNormals(normals, 6);
+    fullMesh_.SetTexCoords(0, texcoords, 6);
+    fullMesh_.UpdateGPUMemory();
+}
+    
+
+void QuickShapes::DrawFullscreenTexture(const Color &color, const Texture2D &tex) {
+    if (fullMesh_.num_vertices() == 0) {
+        initFull();
+    }
+    DrawWithFullscreen(color, &fullMesh_, tex);
+}
+    
+    
+    
+    
+
+void QuickShapes::DrawWithFullscreen(const Color &color, Mesh *mesh, const Texture2D &tex) {
+    if (!fullscreenShader_.initialized()) {
+        fullscreenShader_.AddVertexShaderFromFile(Platform::FindMinGfxShaderFile("fullscreen.vert"));
+        fullscreenShader_.AddFragmentShaderFromFile(Platform::FindMinGfxShaderFile("fullscreen.frag"));
+        fullscreenShader_.LinkProgram();
+    }
+
+    glDisable(GL_DEPTH_TEST);
+    glDepthMask(GL_FALSE);
+    
+    // Activate the shader program
+    fullscreenShader_.UseProgram();
+    
+    // Pass uniforms and textures from C++ to the GPU Shader Program
+    fullscreenShader_.SetUniform("TintColor", color);
+    fullscreenShader_.BindTexture("SurfaceTexture", tex);
+    
+    // Draw the mesh using the shader program
+    mesh->Draw();
+    
+    // Deactivate the shader program
+    fullscreenShader_.StopProgram();
+    
+    glEnable(GL_DEPTH_TEST);
+    glDepthMask(GL_TRUE);
+}
+
+
+DefaultShader* QuickShapes::default_shader() {
+    return &defaultShader_;
+}
+    
+    
+DefaultShader::MaterialProperties* QuickShapes::material() {
+    return &defaultMaterial_;
+}
+
+    
+} // end namespace
diff --git a/dev/MinGfx/src/ray.h b/dev/MinGfx/src/ray.h
index 7374d86..d1b41b6 100644
--- a/dev/MinGfx/src/ray.h
+++ b/dev/MinGfx/src/ray.h
@@ -1,167 +1,166 @@
-/*

- This file is part of the MinGfx Project.

- 

- Copyright (c) 2017,2018 Regents of the University of Minnesota.

- All Rights Reserved.

- 

- Original Author(s) of this File:

-	Dan Keefe, 2018, University of Minnesota

-	

- Author(s) of Significant Updates/Modifications to the File:

-	...

- */

-

-#ifndef SRC_RAY_H_

-#define SRC_RAY_H_

-

-#include <iostream>

-

-#include "aabb.h"

-#include "point3.h"

-#include "vector3.h"

-#include "mesh.h"

-

-

-namespace mingfx {

-

-    

-/** Stores the mathematical object of a ray that begins at an origin (a 3D

- point) and points in a direction (a unit 3D vector).  Rays can intersect

- a variety of other computer graphics objects, such as planes, triangles,

- spheres, 3D meshes, etc.  These intersections can be tested with the

- Intersect...() methods.  The Ray can also be transformed by a Matrix4.

- Example:

- ~~~

- // Create a pick ray from the mouse position

- void MyGraphicsApp::OnLeftMouseDown(const Point2 &pos) {

-    Point2 mouse_xy = PixelsToNormalizedDeviceCoords(pos);

-    float mouse_z = ReadZValueAtPixel(pos);

-    Point3 mouse_3d = GfxMath::ScreenToNearPlane(view_matrix, proj_matrix, mouse_xy, mouse_z);

-    Matrix4 camera_matrix = view_matrix.Inverse();

-    Point3 eye = camera_matrix.ColumnToPoint3(3);

- 

-    Ray pick_ray(eye, mouse_3d - eye);

- 

-    // check to see if the ray intersects a sphere

-    float t;

-    Point3 p;

-    if (pick_ray.IntersectSphere(Point3(0,0,0), 2.0, &t, &p)) {

-        std::cout << "Mouse pointing at sphere!  Intersection point = " << p << std::endl;

-    }

- }

- ~~~

- */

-class Ray {

-public:

-    

-    /// Defaults to a ray at the origin and pointing in the -Z direction

-    Ray();

-    

-    /// Creates a ray from a 3D origin and direction

-    Ray(const Point3 &origin, const Vector3 &direction);

-    

-    /// Ray destructor

-    virtual ~Ray();

-    

-    /// Check for "equality", taking floating point imprecision into account

-    bool operator==(const Ray& other) const;

-    

-    /// Check for "inequality", taking floating point imprecision into account

-    bool operator!=(const Ray& other) const;

-    

-    /// Returns the length of the direction vector

-    float Length() const;

-    

-    /** Checks to see if the ray intersects a plane defined by a point and a normal.

-     If there was an intersection, true is returned, iTime is set to the intersection

-     time, and iPoint is set to the intersection point.  The plane is considered

-     to be 1-sided.  That is the intersection will only occur if the ray hits the

-     plane from its front side as determined by the plane's normal.

-     */

-    bool IntersectPlane(const Point3 &planePt, const Vector3 &planeNormal,

-                        float *iTime, Point3 *iPoint) const;

-    

-    /** Checks to see if the ray intersects a triangle defined by the vertices v1, v2, and v3.

-     The vertices must be provided in counter-clockwise order so that the normal of the

-     triangle can be determined via the right-hand rule.  The intersection will only happen

-     if the ray hits the front side of the triangle.  If there was an intersection,

-     true is returned, iTime is set to the intersection time, and iPoint is set to the intersection point.

-     */

-    bool IntersectTriangle(const Point3 &v1, const Point3 &v2, const Point3 &v3,

-                           float *iTime, Point3 *iPoint) const;

-    

-    /** Checks to see if the ray intersects a quad defined by the vertices v1, v2, v3, and v4.

-     The vertices must be provided in counter-clockwise order so that the normal of the

-     triangle can be determined via the right-hand rule.  The intersection will only happen

-     if the ray hits the front side of the triangle.  If there was an intersection,

-     true is returned, iTime is set to the intersection time, and iPoint is set to the intersection point.

-     */

-    bool IntersectQuad(const Point3 &v1, const Point3 &v2, const Point3 &v3, const Point3 &v4,

-                       float *iTime, Point3 *iPoint) const;

-

-    /** Checks to see if the ray intersects a sphere defined by a center point and a radius.

-     If there was an intersection, true is returned, iTime is set to the intersection time, 

-     and iPoint is set to the intersection point.

-     */

-    bool IntersectSphere(const Point3 &center, float radius,

-                         float *iTime, Point3 *iPoint) const;

-    

-    /** Checks to see if the ray intersects a triangle mesh.  This is a brute-force

-     check over each triangle in the mesh. If there was an intersection, true is returned, 

-     iTime is set to the intersection time, iPoint is set to the intersection point,

-     and iTriangleID is set to the ID of the closest intersected triangle along the ray.

-     */

-    bool IntersectMesh(const Mesh &mesh, float *iTime,

-                       Point3 *iPoint, int *iTriangleID) const;

-    

-    /** Checks to see if the ray intersects a triangle mesh.  This uses a BVH

-     (Bounding Volume Hierarchy) to accelerate the ray-triangle intersection tests.

-     Each mesh can optionally store a BVH.  If a BVH has already been calculated

-     for the mesh (done with Mesh::CalculateBVH()), then this function will be 

-     much faster than the brute-force IntersectMesh() function.  If a BVH has 

-     not already been calculated for the mesh, the first call to FastIntersectMesh()

-     will trigger the mesh to create a BVH (not a fast operation) but then 

-     subsequent calls to FastIntersectMesh() will be fast.

-     */

-    bool FastIntersectMesh(Mesh *mesh, float *iTime,

-                           Point3 *iPoint, int *iTriangleID) const;

-    

-    /** Checks to see if the ray intersects an AABB (Axis-Aligned Bounding Box).

-     Typically, this is the first step of a more detailed intersection test and

-     we don't care about the actual point of intersection, just whether it

-     intersects or not.  So, we don't bother calculating the iPoint.  We get the

-     iTime for free though, so we do return that.  You can calc the iPoint if

-     you want using:

-     ~~~

-     float t;

-     if (ray.IntersectAABB(box, &t)) {

-       Point3 iPoint = ray.origin() + t*ray.direction();

-     }

-     ~~~

-     */

-     bool IntersectAABB(const AABB &box, float *iTime) const;

-    

-    /// Returns the origin

-    Point3 origin() const;

-    

-    /// Returns the direction

-    Vector3 direction() const;

-

-    /// Sets a new origin and direction

-    void set(Point3 newOrigin, Vector3 newDir);

-    

-private:

-    Point3 p_;

-    Vector3 d_;

-};

-

-

-// --- Stream operators ---

-

-std::ostream & operator<< ( std::ostream &os, const Ray &r);

-std::istream & operator>> ( std::istream &is, Ray &r);

-

-    

-} // end namespace

-

-#endif

+/*
+ This file is part of the MinGfx Project.
+ 
+ Copyright (c) 2017,2018 Regents of the University of Minnesota.
+ All Rights Reserved.
+ 
+ Original Author(s) of this File:
+	Dan Keefe, 2018, University of Minnesota
+	
+ Author(s) of Significant Updates/Modifications to the File:
+	...
+ */
+
+#ifndef SRC_RAY_H_
+#define SRC_RAY_H_
+
+#include <iostream>
+
+#include "aabb.h"
+#include "point3.h"
+#include "vector3.h"
+#include "mesh.h"
+
+
+namespace mingfx {
+
+    
+/** Stores the mathematical object of a ray that begins at an origin (a 3D
+ point) and points in a direction (a unit 3D vector).  Rays can intersect
+ a variety of other computer graphics objects, such as planes, triangles,
+ spheres, 3D meshes, etc.  These intersections can be tested with the
+ Intersect...() methods.  The Ray can also be transformed by a Matrix4.
+ Example:
+ ~~~
+ // Create a pick ray from the mouse position
+ void MyGraphicsApp::OnLeftMouseDown(const Point2 &mouse_in_2d_pixels) {
+    Point2 mouse_in_2d_ndc = PixelsToNormalizedDeviceCoords(mouse_in_2d_pixels);
+    Point3 mouse_in_3d = GfxMath::ScreenToNearPlane(view_matrix, proj_matrix, mouse_in_2d_ndc);
+    Matrix4 camera_matrix = view_matrix.Inverse();
+    Point3 eye = camera_matrix.ColumnToPoint3(3);
+ 
+    Ray pick_ray(eye, mouse_in_3d - eye);
+ 
+    // check to see if the ray intersects a sphere
+    float t;
+    Point3 p;
+    if (pick_ray.IntersectSphere(Point3(0,0,0), 2.0, &t, &p)) {
+        std::cout << "Mouse pointing at sphere!  Intersection point = " << p << std::endl;
+    }
+ }
+ ~~~
+ */
+class Ray {
+public:
+    
+    /// Defaults to a ray at the origin and pointing in the -Z direction
+    Ray();
+    
+    /// Creates a ray from a 3D origin and direction
+    Ray(const Point3 &origin, const Vector3 &direction);
+    
+    /// Ray destructor
+    virtual ~Ray();
+    
+    /// Check for "equality", taking floating point imprecision into account
+    bool operator==(const Ray& other) const;
+    
+    /// Check for "inequality", taking floating point imprecision into account
+    bool operator!=(const Ray& other) const;
+    
+    /// Returns the length of the direction vector
+    float Length() const;
+    
+    /** Checks to see if the ray intersects a plane defined by a point and a normal.
+     If there was an intersection, true is returned, iTime is set to the intersection
+     time, and iPoint is set to the intersection point.  The plane is considered
+     to be 1-sided.  That is the intersection will only occur if the ray hits the
+     plane from its front side as determined by the plane's normal.
+     */
+    bool IntersectPlane(const Point3 &planePt, const Vector3 &planeNormal,
+                        float *iTime, Point3 *iPoint) const;
+    
+    /** Checks to see if the ray intersects a triangle defined by the vertices v1, v2, and v3.
+     The vertices must be provided in counter-clockwise order so that the normal of the
+     triangle can be determined via the right-hand rule.  The intersection will only happen
+     if the ray hits the front side of the triangle.  If there was an intersection,
+     true is returned, iTime is set to the intersection time, and iPoint is set to the intersection point.
+     */
+    bool IntersectTriangle(const Point3 &v1, const Point3 &v2, const Point3 &v3,
+                           float *iTime, Point3 *iPoint) const;
+    
+    /** Checks to see if the ray intersects a quad defined by the vertices v1, v2, v3, and v4.
+     The vertices must be provided in counter-clockwise order so that the normal of the
+     triangle can be determined via the right-hand rule.  The intersection will only happen
+     if the ray hits the front side of the triangle.  If there was an intersection,
+     true is returned, iTime is set to the intersection time, and iPoint is set to the intersection point.
+     */
+    bool IntersectQuad(const Point3 &v1, const Point3 &v2, const Point3 &v3, const Point3 &v4,
+                       float *iTime, Point3 *iPoint) const;
+
+    /** Checks to see if the ray intersects a sphere defined by a center point and a radius.
+     If there was an intersection, true is returned, iTime is set to the intersection time, 
+     and iPoint is set to the intersection point.
+     */
+    bool IntersectSphere(const Point3 &center, float radius,
+                         float *iTime, Point3 *iPoint) const;
+    
+    /** Checks to see if the ray intersects a triangle mesh.  This is a brute-force
+     check over each triangle in the mesh. If there was an intersection, true is returned, 
+     iTime is set to the intersection time, iPoint is set to the intersection point,
+     and iTriangleID is set to the ID of the closest intersected triangle along the ray.
+     */
+    bool IntersectMesh(const Mesh &mesh, float *iTime,
+                       Point3 *iPoint, int *iTriangleID) const;
+    
+    /** Checks to see if the ray intersects a triangle mesh.  This uses a BVH
+     (Bounding Volume Hierarchy) to accelerate the ray-triangle intersection tests.
+     Each mesh can optionally store a BVH.  If a BVH has already been calculated
+     for the mesh (done with Mesh::CalculateBVH()), then this function will be 
+     much faster than the brute-force IntersectMesh() function.  If a BVH has 
+     not already been calculated for the mesh, the first call to FastIntersectMesh()
+     will trigger the mesh to create a BVH (not a fast operation) but then 
+     subsequent calls to FastIntersectMesh() will be fast.
+     */
+    bool FastIntersectMesh(Mesh *mesh, float *iTime,
+                           Point3 *iPoint, int *iTriangleID) const;
+    
+    /** Checks to see if the ray intersects an AABB (Axis-Aligned Bounding Box).
+     Typically, this is the first step of a more detailed intersection test and
+     we don't care about the actual point of intersection, just whether it
+     intersects or not.  So, we don't bother calculating the iPoint.  We get the
+     iTime for free though, so we do return that.  You can calc the iPoint if
+     you want using:
+     ~~~
+     float t;
+     if (ray.IntersectAABB(box, &t)) {
+       Point3 iPoint = ray.origin() + t*ray.direction();
+     }
+     ~~~
+     */
+     bool IntersectAABB(const AABB &box, float *iTime) const;
+    
+    /// Returns the origin
+    Point3 origin() const;
+    
+    /// Returns the direction
+    Vector3 direction() const;
+
+    /// Sets a new origin and direction
+    void set(Point3 newOrigin, Vector3 newDir);
+    
+private:
+    Point3 p_;
+    Vector3 d_;
+};
+
+
+// --- Stream operators ---
+
+std::ostream & operator<< ( std::ostream &os, const Ray &r);
+std::istream & operator>> ( std::istream &is, Ray &r);
+
+    
+} // end namespace
+
+#endif
diff --git a/dev/a2-carsoccer/.gitignore b/dev/a2-carsoccer/.gitignore
new file mode 100644
index 0000000..dd1a9a8
--- /dev/null
+++ b/dev/a2-carsoccer/.gitignore
@@ -0,0 +1,2 @@
+config.h
+build
diff --git a/dev/a2-carsoccer/CMakeLists.txt b/dev/a2-carsoccer/CMakeLists.txt
new file mode 100644
index 0000000..0d67553
--- /dev/null
+++ b/dev/a2-carsoccer/CMakeLists.txt
@@ -0,0 +1,176 @@
+# Original Author(s) of this File: 
+#   Daniel Keefe, 2017, University of Minnesota
+#  
+# Author(s) of Significant Updates/Modifications to the File:
+#   ... 
+
+
+
+# You are encouraged to copy this example, move it outside of the MinGfx directory, and use
+# it as a starting point for your project.  When you do this, you'll have to edit the
+# following line as needed to point to the MinGfx install prefix used on your system.
+
+# !!!!!!!!!!!!! EDIT THE FOLLOWING LINE AS NEEDED !!!!!!!!!!!!! 
+list(APPEND CMAKE_PREFIX_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../build/install ../..)
+
+
+
+
+
+#### BASIC PROJECT SETUP ####
+
+project(a2-carsoccer)
+
+# Using 3.9 to get a modern version of FindOpenGL.cmake
+cmake_minimum_required (VERSION 3.9) 
+
+# Dependencies that are auto-downloaded, built, and installed for you will go in the 
+# directory pointed to by the CMAKE_INSTALL_PREFIX.  It defaults to a location inside
+# the build directory.
+if (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT OR "${CMAKE_INSTALL_PREFIX}" STREQUAL "")
+    set (CMAKE_INSTALL_PREFIX "${CMAKE_BINARY_DIR}/install" CACHE PATH "default install path" FORCE )
+endif()
+
+# Add to paths cmake uses to search for scripts, modules, and config packages
+list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_INSTALL_PREFIX})
+list(INSERT CMAKE_PREFIX_PATH 0 ${CMAKE_INSTALL_PREFIX})
+
+include(MessageMacros)
+h1("Building ${PROJECT_NAME}")
+h2("Configuring paths")
+
+message(STATUS "Module path: ${CMAKE_MODULE_PATH}")
+message(STATUS "Prefix path: ${CMAKE_PREFIX_PATH}")
+message(STATUS "Install prefix: ${CMAKE_INSTALL_PREFIX}")
+
+set(DATA_DIR_BUILD ${CMAKE_CURRENT_SOURCE_DIR}/data)
+set(DATA_DIR_INSTALL ${CMAKE_INSTALL_PREFIX}/share/${PROJECT_NAME}/data)
+
+message(STATUS "Data dir (in build tree): ${DATA_DIR_BUILD}")
+message(STATUS "Data dir (in install tree): ${DATA_DIR_INSTALL}")
+
+# Configure a header file to pass some of the CMake settings to the source code
+configure_file(
+    ${CMAKE_CURRENT_SOURCE_DIR}/config.h.in
+    ${CMAKE_CURRENT_SOURCE_DIR}/config.h
+)
+
+#### SOURCE FOR THIS PROJECT ####
+h2("Configuring source files")
+
+set(SOURCEFILES
+    ball.cc
+    car.cc
+    car_soccer.cc
+    main.cc
+)
+
+set(HEADERFILES
+    ball.h
+    car_soccer.h
+    car.h
+    config.h
+)
+
+set(EXTRAFILES
+    config.h.in
+    README.md
+)
+
+set_source_files_properties(${EXTRAFILES} PROPERTIES HEADER_FILE_ONLY TRUE)
+
+
+
+#### COMPILE OPTIONS ####
+
+h2("Configuring Compiler Options")
+
+
+
+message(STATUS "Building for " ${CMAKE_SYSTEM_NAME} ".")
+
+# Linux specific
+if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+  add_definitions(-DLINUX)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
+endif()
+
+
+# Apple specific
+if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  add_definitions(-DOSX)
+
+  # RPATH settings, see https://cmake.org/Wiki/CMake_RPATH_handling
+  set(CMAKE_MACOSX_RPATH ON)
+
+  # use, i.e. don't skip the full RPATH for the build tree
+  SET(CMAKE_SKIP_BUILD_RPATH  FALSE)
+
+  # when building, don't use the install RPATH already
+  # (but later on when installing)
+  SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE) 
+
+  SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
+
+  # add the automatically determined parts of the RPATH
+  # which point to directories outside the build tree to the install RPATH
+  SET(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+
+  # the RPATH to be used when installing, but only if it's not a system directory
+  LIST(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
+  IF("${isSystemDir}" STREQUAL "-1")
+     SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
+  ENDIF("${isSystemDir}" STREQUAL "-1")
+
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
+endif()
+
+
+# Windows specific
+if (WIN32)
+  add_definitions(-DWIN32)
+endif()
+
+
+
+
+#### DEFINE TARGET(S) ####
+
+h2("Defining Target(s)")
+
+add_executable(${PROJECT_NAME} ${SOURCEFILES} ${HEADERFILES} ${EXTRAFILES})
+
+
+
+#### FIND AND ADD DEPENDENCIES ####
+
+h2("Adding Dependencies")
+set(EXTERNAL_DIR external)
+
+
+# MinGfx (linked with an imported cmake target so no need to specify include dirs)
+# This will try to find MinGfxConfig.cmake, which should have been installed under
+# CMAKE_INSTALL_PREFIX/lib/cmake/MinGfx when you installed the MinGfx Toolkit.
+find_package(MinGfx REQUIRED)
+target_link_libraries(${PROJECT_NAME} PUBLIC MinGfx::MinGfx)
+
+
+# Add dependency on OpenGL
+include(UseOpenGL)
+UseOpenGL(${PROJECT_NAME} PUBLIC ${EXTERNAL_DIR})
+
+
+
+#### INSTALL TARGET(S) ####
+
+h2("Configuring Install Target")
+
+# The install locations are relative to the CMAKE_INSTALL_PREFIX variable
+install(TARGETS ${PROJECT_NAME} RUNTIME DESTINATION bin)
+
+install(
+    DIRECTORY data/
+    DESTINATION ${DATA_DIR_INSTALL}
+    OPTIONAL
+)
diff --git a/dev/a2-carsoccer/README.md b/dev/a2-carsoccer/README.md
new file mode 100644
index 0000000..9c30158
--- /dev/null
+++ b/dev/a2-carsoccer/README.md
@@ -0,0 +1 @@
+# My solution to Assignment 2
diff --git a/dev/a2-carsoccer/ball.cc b/dev/a2-carsoccer/ball.cc
new file mode 100644
index 0000000..8289905
--- /dev/null
+++ b/dev/a2-carsoccer/ball.cc
@@ -0,0 +1,58 @@
+#include "ball.h"
+
+/// The constructor sets the radius and calls Reset() to start the ball at
+/// the center of the field
+Ball::Ball() : radius_(2.6f) {
+    Reset();
+}
+    
+Ball::~Ball() {
+    
+}
+
+
+float Ball::radius() {
+    return radius_;
+}
+    
+Point3 Ball::position() {
+    return position_;
+}
+
+void Ball::set_position(const Point3 &p) {
+    position_ = p;
+}
+
+Vector3 Ball::velocity() {
+    return velocity_;
+}
+
+void Ball::set_velocity(const Vector3 &v) {
+    velocity_ = v;
+}
+
+void Ball::Reset() {
+    position_ = Point3(0, radius_, 0);
+    
+    float a = GfxMath::PI * rand()/RAND_MAX;
+    velocity_ = Vector3(25*cos(a), 10, 25*sin(a));
+}
+
+void Ball::Draw(QuickShapes quickShapes, Matrix4 modelMatrix, Matrix4 viewMatrix, Matrix4 projMatrix) {
+    Color ballcol(1,1,1);
+    Matrix4 Mball =
+        Matrix4::Translation(position_- Point3(0,0,0)) *
+        Matrix4::Scale(Vector3(radius_, radius_, radius_));
+    quickShapes.DrawSphere(modelMatrix * Mball, viewMatrix, projMatrix, ballcol);
+    
+    // Draw the ball's shadow -- this is a bit of a hack, scaling Y by zero
+    // flattens the sphere into a pancake, which we then draw just a bit
+    // above the ground plane.
+    Color shadowcol(0.2f, 0.4f, 0.15f);
+    Matrix4 Mshadow =
+        Matrix4::Translation(Vector3(position_[0], -0.1f, position_[2])) *
+        Matrix4::Scale(Vector3(radius_, 0, radius_)) *
+        Matrix4::RotationX(90);
+    quickShapes.DrawSphere(modelMatrix * Mshadow, viewMatrix, projMatrix, shadowcol);
+}
+
diff --git a/dev/a2-carsoccer/ball.h b/dev/a2-carsoccer/ball.h
new file mode 100644
index 0000000..0fa107e
--- /dev/null
+++ b/dev/a2-carsoccer/ball.h
@@ -0,0 +1,39 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+ */
+
+#ifndef BALL_H_
+#define BALL_H_
+
+#include <mingfx.h>
+using namespace mingfx;
+
+/// Small class representing the ball.  Feel free to add additional member variables and functions if you wish.
+class Ball {
+public:
+    
+    Ball();
+    virtual ~Ball();
+    
+    // The same radius is used to draw the ball and to calculate physics for the ball
+    float radius();
+
+    // Current 3D position
+    Point3 position();
+    void set_position(const Point3 &p);
+
+    // Current 3D velocity
+    Vector3 velocity();
+    void set_velocity(const Vector3 &v);
+    
+    // Resets the ball's position and velocity to initial values.
+    void Reset();
+    
+    void Draw(QuickShapes quickShapes, Matrix4 modelMatrix, Matrix4 viewMatrix, Matrix4 projMatrix);
+    
+private:
+    Point3 position_;
+    Vector3 velocity_;
+    float radius_;
+};
+
+#endif
diff --git a/dev/a2-carsoccer/car.cc b/dev/a2-carsoccer/car.cc
new file mode 100644
index 0000000..3b9bb5c
--- /dev/null
+++ b/dev/a2-carsoccer/car.cc
@@ -0,0 +1,66 @@
+#include "car.h"
+
+/// The constructor sets the static properties of the car, like its size,
+/// and then calls Reset() to reset the position, velocity, and any other
+/// dynamic variables that change during game play.
+Car::Car() : size_(3,2,4), collision_radius_(2.5) {
+    Reset();
+}
+
+Car::~Car() {
+}
+
+
+float Car::collision_radius() {
+    return collision_radius_;
+    
+}
+
+Vector3 Car::size() {
+    return size_;
+}
+
+Point3 Car::position() {
+    return position_;
+}
+
+void Car::set_position(const Point3 &p) {
+    position_ = p;
+}
+
+Vector3 Car::forward() {
+    return forward_;
+}
+
+void Car::set_forward(const Vector3 &v) {
+    forward_ = v;
+}
+
+float Car::speed() {
+    return speed_;
+}
+
+void Car::set_speed(float s) {
+    speed_ = s;
+}
+
+Vector3 Car::velocity() {
+    return speed_ * forward_;
+}
+
+
+void Car::Reset() {
+    position_ = Point3(0, size_[1]/2, 45);
+    forward_ = Vector3(0, 0, -1);
+    speed_ = 0.0f;
+}
+
+void Car::Draw(QuickShapes quickShapes, Matrix4 modelMatrix, Matrix4 viewMatrix, Matrix4 projMatrix) {
+    Color carcol(0.8f, 0.2f, 0.2f);
+    Matrix4 Mcar =
+        Matrix4::Translation(position_ - Point3(0,0,0)) *
+        Matrix4::LookAt(Point3(0,0,0), Point3(0,0,0) + forward_, Vector3(0,1,0)).Inverse() *
+        Matrix4::Scale(size_) *
+        Matrix4::Scale(Vector3(0.5f, 0.5f, 0.5f));
+    quickShapes.DrawCube(modelMatrix * Mcar, viewMatrix, projMatrix, carcol);
+}
diff --git a/dev/a2-carsoccer/car.h b/dev/a2-carsoccer/car.h
new file mode 100644
index 0000000..6746a56
--- /dev/null
+++ b/dev/a2-carsoccer/car.h
@@ -0,0 +1,52 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+ */
+
+#ifndef CAR_H_
+#define CAR_H_
+
+#include <mingfx.h>
+using namespace mingfx;
+
+/// Small class representing the car.  Feel free to add additional member variables and functions if you wish.
+class Car {
+public:
+    Car();
+    virtual ~Car();
+        
+    // Size is the size of the box drawn to represent the car in the X, Y, and Z dimensions
+    Vector3 size();
+
+    // Radius of the bounding sphere used to calculate approximate physics
+    float collision_radius();
+
+    // 3D position of the car
+    Point3 position();
+    void set_position(const Point3 &p);
+
+    // The unit vector direction the car is pointing.  Since the car drives around on the
+    // Y=0 plane, this vector will always have a y coordinate = 0
+    Vector3 forward();
+    void set_forward(const Vector3 &v);
+
+    // The speed of the car can be positive (moving forward) or negative (moving in reverse)
+    float speed();
+    void set_speed(float s);
+    
+    // Current 3D velocity, computed as speed_ * forward_
+    Vector3 velocity();
+    
+    // Resets the position, speed, and forward direction to the car's starting point
+    void Reset();
+    
+    // Draws a simple box shape for the car at the proper position and rotated to face forward
+    void Draw(QuickShapes quickShapes, Matrix4 modelMatrix, Matrix4 viewMatrix, Matrix4 projMatrix);
+    
+private:
+    Vector3 size_;
+    float collision_radius_;
+    Point3 position_;
+    Vector3 forward_;
+    float speed_;
+};
+
+#endif
diff --git a/dev/a2-carsoccer/car_soccer.cc b/dev/a2-carsoccer/car_soccer.cc
new file mode 100644
index 0000000..c5619a8
--- /dev/null
+++ b/dev/a2-carsoccer/car_soccer.cc
@@ -0,0 +1,134 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+ */
+
+#include "car_soccer.h"
+#include "config.h"
+
+
+// Remember in C++, the .h file list all the functions and member variables that are part of the class!
+// Look there first to understand what is part of the CarSoccer class, then look below to see how each
+// function is implemented.
+
+
+CarSoccer::CarSoccer() : GraphicsApp(1024,768, "Car Soccer") {
+    // If you are having trouble driving the car with the keybaord, you can set this to true to use
+    // the mouse instead.  The mouse controls are based on the postion of the mouse cursor on the window.
+    // There is a "dead zone" in the middle of the window, and if you move the mouse up/down or left/right
+    // outside of that zone, it is like pushing the up/down and/or left/right keys on the keyboard
+    use_mouse_ = false;
+        
+    // Define a search path for finding data files (images and shaders)
+    searchPath_.push_back(".");
+    searchPath_.push_back("./data");
+    searchPath_.push_back(DATA_DIR_INSTALL);
+    searchPath_.push_back(DATA_DIR_BUILD);
+}
+
+CarSoccer::~CarSoccer() {
+}
+
+
+void CarSoccer::OnMouseMove(const Point2& pos, const Vector2& delta)
+{
+    mouse_pos_ = PixelsToNormalizedDeviceCoords(pos);
+}
+
+void CarSoccer::OnSpecialKeyDown(int key, int scancode, int modifiers) {
+    if (key == GLFW_KEY_SPACE) {
+        // Here's where you could call some form of launch_ball();
+        ball_.Reset();
+    }
+}
+
+/// This is a little utility function that is helpful.  It treats the arrow keys like a joystick or D-pad on a game controller
+/// and returns the direction you are pressing as a 2D vector, taking into account the fact that you might be holding
+/// down more than one key at a time.
+Vector2 CarSoccer::joystick_direction() {
+    Vector2 dir;
+
+    if (use_mouse_) {
+        // threshold defines the size of the "dead zone" in the middle of the screen
+        // if the mouse's x,y position falls outside of this, then it is like pushing
+        // the corresponding key on the keyboard
+        const float threshold = 0.2f;
+        dir[0] = 0;
+        if (mouse_pos_[0] < -threshold) {
+            dir[0] = -1;
+        }
+        else if (mouse_pos_[0] > threshold) {
+            dir[0] = 1;
+        }
+        dir[1] = 0;
+        if (mouse_pos_[1] < -threshold) {
+            dir[1] = -1;
+        }
+        else if (mouse_pos_[1] > threshold) {
+            dir[1] = 1;
+        }
+    }
+    else {
+        // the default user interface is to use the arrow keys on the keyboard.
+        // like a D-pad on a game controller, you can hold more than one key down at a time if you want.
+        if (IsKeyDown(GLFW_KEY_LEFT))
+            dir[0]--;
+        if (IsKeyDown(GLFW_KEY_RIGHT))
+            dir[0]++;
+        if (IsKeyDown(GLFW_KEY_UP))
+            dir[1]++;
+        if (IsKeyDown(GLFW_KEY_DOWN))
+            dir[1]--;
+    }
+
+    return dir;
+}
+
+// dt is for "Delta Time", the elapsed time in seconds since the last frame
+void CarSoccer::UpdateSimulation(double dt) {
+    Vector2 dpad_dir = joystick_direction();
+    std::cout << "D-Pad Direction: " << dpad_dir << std::endl;
+
+    // Here's where you shound do your "simulation", updating the positions of the
+    // car and ball based on the elapsed time and checking for collisions.  Filling
+    // in this routine is the main part of the assignment.
+
+    // Example: This is not the "correct way" to drive the car, but this code
+    // will at least move the car around for testing
+    float metersPerSec = 10.0f;
+    car_.set_position(car_.position() + metersPerSec * Vector3(dpad_dir[0], 0, -dpad_dir[1]) * dt);
+    
+}
+
+
+void CarSoccer::InitOpenGL() {
+    // Set up the camera in a good position to see the entire field
+    projMatrix_ = Matrix4::Perspective(60, aspect_ratio(), 1, 1000);
+    modelMatrix_ = Matrix4::LookAt(Point3(0,60,70), Point3(0,0,10), Vector3(0,1,0));
+ 
+    // Set a background color for the screen (don't worry if you get a depricated warning on this line in OSX)
+    glClearColor(0.8f, 0.8f, 0.8f, 1.0f);
+    
+    // Load some image files we'll use
+    fieldTex_.InitFromFile(Platform::FindFile("pitch.png", searchPath_));
+    crowdTex_.InitFromFile(Platform::FindFile("crowd.png", searchPath_));
+}
+
+
+void CarSoccer::DrawUsingOpenGL() {
+    // Draw the crowd as a fullscreen background image
+    quickShapes_.DrawFullscreenTexture(Color(1,1,1), crowdTex_);
+
+    // Draw the car and the ball
+    car_.Draw(quickShapes_, modelMatrix_, viewMatrix_, projMatrix_);
+    ball_.Draw(quickShapes_, modelMatrix_, viewMatrix_, projMatrix_);
+    
+    // Draw the field with the field texture on it.
+    Color col(16.0f/255.0f, 46.0f/255.0f, 9.0f/255.0f);
+    Matrix4 M = Matrix4::Translation(Vector3(0.0f, -0.201f, 0.0f)) * Matrix4::Scale(Vector3(50.0f, 1.0f, 60.0f));
+    quickShapes_.DrawSquare(modelMatrix_ * M, viewMatrix_, projMatrix_, col);
+    M = Matrix4::Translation(Vector3(0.0f, -0.2f, 0.0f)) * Matrix4::Scale(Vector3(40.0f, 1.0f, 50.0f));
+    quickShapes_.DrawSquare(modelMatrix_ * M, viewMatrix_, projMatrix_, Color(1,1,1), fieldTex_);
+    
+    // You should add drawing the goals and the boundary of the playing area
+    // using quickShapes_.DrawLines()
+    
+}
diff --git a/dev/a2-carsoccer/car_soccer.h b/dev/a2-carsoccer/car_soccer.h
new file mode 100644
index 0000000..9982238
--- /dev/null
+++ b/dev/a2-carsoccer/car_soccer.h
@@ -0,0 +1,84 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+ */
+
+#ifndef CAR_SOCCER_H_
+#define CAR_SOCCER_H_
+
+#include <mingfx.h>
+using namespace mingfx;
+
+#include "ball.h"
+#include "car.h"
+
+
+// The main class for the Car Soccer application
+class CarSoccer : public GraphicsApp {
+public:
+    CarSoccer();
+    virtual ~CarSoccer();
+
+    /// Called whenever the mouse moves
+    void OnMouseMove(const Point2& pos, const Vector2& delta);
+
+    /// This is called when special keys like SPACEBAR are pressed
+    void OnSpecialKeyDown(int key, int scancode, int modifiers);
+
+    /// This is called once each frame.  dt is "delta time", the time elapsed
+    /// since the last call.
+    void UpdateSimulation(double dt);
+    
+    /// This is called when it is time to initialize graphics objects, like
+    /// texture files.
+    void InitOpenGL();
+    
+    /// This is called once each frame, and you should draw the scene inside
+    /// this function.
+    void DrawUsingOpenGL();
+    
+    /// This is a little utility function that is helpful.  It treats the
+    /// arrow keys like a joystick and returns the direction you are pressing
+    /// as a 2D vector, taking into account the fact that you might be holding
+    /// down more than one key at a time.
+    Vector2 joystick_direction();
+    
+    // Feel free to add more functions here as needed.
+
+    
+private:
+
+    // Simulation objects/parameters:
+    
+    // We suggest you start with the Car and Ball objects provided, adding new
+    // member variables to those classes if you need to.  You'll probably want
+    // to store some other data for the simulation here too, like some value
+    // for gravity.
+    Car car_;
+    Ball ball_;
+    
+    
+    // Support for drawing some simple shapes:
+    QuickShapes quickShapes_;
+    
+    // Images to use as textures:
+    Texture2D fieldTex_;
+    Texture2D crowdTex_;
+
+    // Control the computer graphics camera (we'll learn about this in a few weeks):
+    Matrix4 modelMatrix_;
+    Matrix4 viewMatrix_;
+    Matrix4 projMatrix_;
+    
+    // A list of paths to search for data files (images):
+    std::vector<std::string> searchPath_;
+    
+    // Set this to true if you want to use the mouse to control the car rather than the keyboard
+    bool use_mouse_;
+
+    // Mouse position in Normalized Device Coordinates, 
+    // meaning -1 to +1 in both X and Y.  (0,0) is the
+    // center of the screen
+    Point2 mouse_pos_;
+};
+
+
+#endif
diff --git a/dev/a2-carsoccer/cmake/DownloadHelper.txt.in b/dev/a2-carsoccer/cmake/DownloadHelper.txt.in
new file mode 100644
index 0000000..fb29bff
--- /dev/null
+++ b/dev/a2-carsoccer/cmake/DownloadHelper.txt.in
@@ -0,0 +1,26 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+# This is a "helper" cmake project -- the only thing this project does is download
+# the external project.  So, the configure, build, install, and test commands for 
+# ExternalProject_Add() are intentionally set as NOPs.  
+
+cmake_minimum_required (VERSION 3.9) 
+
+project(@EXT_PROJECT_NAME@-download)
+
+include(ExternalProject)
+ExternalProject_Add(
+  @EXT_PROJECT_NAME@
+  SOURCE_DIR "@DOWNLOAD_DIR@/@EXT_PROJECT_NAME@/src"
+  BINARY_DIR "@DOWNLOAD_DIR@/@EXT_PROJECT_NAME@/download-helper"
+  @DOWNLOAD_OPTIONS@
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND ""
+  INSTALL_COMMAND ""
+  TEST_COMMAND ""
+  LOG_DOWNLOAD ON
+  GIT_PROGRESS 1
+)
+
+
diff --git a/dev/a2-carsoccer/cmake/ExternalProjectDownloadBuildInstall.cmake b/dev/a2-carsoccer/cmake/ExternalProjectDownloadBuildInstall.cmake
new file mode 100644
index 0000000..ce12d1d
--- /dev/null
+++ b/dev/a2-carsoccer/cmake/ExternalProjectDownloadBuildInstall.cmake
@@ -0,0 +1,98 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+
+# Calling CMAKE_CURRENT_LIST_DIR inside a function returns the list dir of the calling script
+# but we want the list dir of this file in order to find the DownloadHelper.txt.in file, which
+# should be stored right next to this one.  So, defining this variable outside the scope of the
+# functions below.
+set(DIR_OF_THIS_FILE ${CMAKE_CURRENT_LIST_DIR})  
+
+
+
+# Usage:  
+# ExternalProject_Download(
+#     # This first argument is the name of the project to download.  It is required:
+#     glm
+#
+#     # Additional arguments specify how to download the project using GIT, SVN, CVS, or URL.
+#     # These can be any of the arguments used for the downloading step of the cmake builtin
+#     # ExternalProject_Add command. 
+#     GIT_REPOSITORY "https://github.com/g-truc/glm.git"
+#     GIT_TAG master
+#     etc..
+# )
+function(ExternalProject_Download EXT_PROJECT_NAME DOWNLOAD_DIR)
+
+    include(MessageMacros)
+    h1("BEGIN EXTERNAL PROJECT DOWNLOAD (${EXT_PROJECT_NAME}).")
+
+    h2("Creating a download helper project for ${EXT_PROJECT_NAME}.")
+
+    set(DOWNLOAD_OPTIONS ${ARGN})
+    string (REGEX REPLACE "(^|[^\\\\]);" "\\1 " DOWNLOAD_OPTIONS "${DOWNLOAD_OPTIONS}")
+
+
+    file(MAKE_DIRECTORY ${DOWNLOAD_DIR}/${EXT_PROJECT_NAME})
+    configure_file(
+        ${DIR_OF_THIS_FILE}/DownloadHelper.txt.in 
+        ${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper/CMakeLists.txt
+    )
+
+    h2("Generating build files for the ${EXT_PROJECT_NAME} download helper project.")
+    execute_process(COMMAND "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" . WORKING_DIRECTORY "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper")
+
+    h2("Building the ${EXT_PROJECT_NAME} download helper project.  (This actually performs the download and may take some time...)")
+    execute_process(COMMAND "${CMAKE_COMMAND}" --build . WORKING_DIRECTORY "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper")
+
+    h2("Completed download of external project ${EXT_PROJECT_NAME}.")
+
+endfunction()
+
+
+# Usage:  
+# ExternalProject_BuildAndInstallNow(
+#     # This first argument is the name of the external project to download.  It is required:
+#     VRPN
+#     # This second argument is the relative path from ${EXTERNAL_DIR_NAME}/projectname/ to the project's
+#     # main CMakeLists.txt file:
+#     src
+#
+#     # Additional arguments are passed on as options to the cmake build file generator
+#     -DVRPN_BUILD_DIRECTSHOW_VIDEO_SERVER=OFF
+#     -DVRPN_BUILD_HID_GUI=OFF
+#     etc..
+# )
+function(ExternalProject_BuildAndInstallNow EXT_PROJECT_NAME DOWNLOAD_DIR RELPATH_TO_CMAKELISTS)
+
+    include(MessageMacros)
+    h1("BEGIN EXTERNAL PROJECT BUILD AND INSTALL (${EXT_PROJECT_NAME}).")
+
+    # any extra args to the function are interpreted as arguments for the cmake config process
+    set(CMAKE_CONFIG_OPTIONS ${ARGN})
+
+    # always set the install prefix to be the same as for the main project
+    list(APPEND CMAKE_CONFIG_OPTIONS -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX})
+
+    #string (REGEX REPLACE "(^|[^\\\\]);" "\\1 " CMAKE_CONFIG_OPTIONS "${CMAKE_CONFIG_OPTIONS}")
+
+
+    set(SRC_DIR "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/${RELPATH_TO_CMAKELISTS}")
+    set(BUILD_DIR "${CMAKE_BINARY_DIR}/external/${EXT_PROJECT_NAME}")
+
+    file(MAKE_DIRECTORY ${BUILD_DIR})
+
+    h2("Generating build files for external project ${EXT_PROJECT_NAME}.")
+    message(STATUS "Using source dir: ${SRC_DIR}")
+    message(STATUS "Using build dir: ${BUILD_DIR}")
+    message(STATUS "Config options: ${CMAKE_CONFIG_OPTIONS}")
+
+    execute_process(COMMAND "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" ${SRC_DIR} ${CMAKE_CONFIG_OPTIONS} WORKING_DIRECTORY ${BUILD_DIR})
+
+    h2("Building external project ${EXT_PROJECT_NAME}.  (This may take some time...)")
+    execute_process(COMMAND "${CMAKE_COMMAND}" --build ${BUILD_DIR} --target install)
+
+    h2("Completed external build of ${EXT_PROJECT_NAME}.")
+
+endfunction()
+
diff --git a/dev/a2-carsoccer/cmake/MessageMacros.cmake b/dev/a2-carsoccer/cmake/MessageMacros.cmake
new file mode 100644
index 0000000..4628e5c
--- /dev/null
+++ b/dev/a2-carsoccer/cmake/MessageMacros.cmake
@@ -0,0 +1,17 @@
+# This file is part of the MinVR cmake build system.  
+# See the main MinVR/CMakeLists.txt file for authors, copyright, and license info.
+
+
+macro(h1 TITLE)
+  string(TOUPPER ${TITLE} TITLE)
+  message(STATUS "\n\n==== ${TITLE} ====")
+endmacro()
+
+macro(h2 TITLE)
+  message(STATUS "\n* ${TITLE}")
+endmacro()
+
+macro(h3 TITLE)
+  message(STATUS "- ${TITLE}")
+endmacro()
+
diff --git a/dev/a2-carsoccer/cmake/UseOpenGL.cmake b/dev/a2-carsoccer/cmake/UseOpenGL.cmake
new file mode 100644
index 0000000..2ec5ffb
--- /dev/null
+++ b/dev/a2-carsoccer/cmake/UseOpenGL.cmake
@@ -0,0 +1,52 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+# Either finds a pre-installed version or complains.
+
+# Usage: In your CMakeLists.txt, somewhere after you define the target that depends
+# on the OpenGL library (typical with something like add_executable(${PROJECT_NAME} ...) 
+# or add_library(${PROJECT_NAME} ...)), add the following two lines:
+
+#    include(UseOpenGL)
+#    UseOpenGL(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/external)
+
+# The second argument can be either PUBLIC, PRIVATE, or INTERFACE, following the keyword
+# usage described here: 
+# https://cmake.org/cmake/help/latest/command/target_include_directories.html
+
+# The third argument is the directory to use for downloading the external project if
+# autobuild is used.
+
+
+
+macro(UseOpenGL YOUR_TARGET INTERFACE_PUBLIC_OR_PRIVATE DOWNLOAD_DIR)
+
+    message(STATUS "Searching for OpenGL...")
+
+	# Check to see if the library is already installed on the system    
+    # CMake ships with FindOpenGL.cmake and in CMake 3.9+ it defines
+    # the imported targets OpenGL::GL and OpenGL::GLU.  Using these is
+    # now the preferred way to link with OpenGL and all of its dependencies.
+	# See https://cmake.org/cmake/help/v3.9/module/FindOpenGL.html
+	find_package(OpenGL)
+
+	if (NOT ${OPENGL_FOUND})
+	    message(FATAL_ERROR "OpenGL was not found on the system.  MinGfx can auto-download and build many dependencies for you, but not OpenGL. It should come pre-installed on your system.")
+	endif()
+
+    message(STATUS "Ok: OpenGL Found.")
+    message(STATUS "OpenGL headers: ${OPENGL_INCLUDE_DIR}")
+    message(STATUS "OpenGL libs: ${OPENGL_LIBRARIES}")
+
+
+    message(STATUS "Linking target ${YOUR_TARGET} with ${INTERFACE_PUBLIC_OR_PRIVATE} dependency OpenGL::GL.")
+    target_link_libraries(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} OpenGL::GL)
+
+    if (${OPENGL_GLU_FOUND})
+        message(STATUS "Linking target ${YOUR_TARGET} with ${INTERFACE_PUBLIC_OR_PRIVATE} dependency OpenGL::GLU.")
+        target_link_libraries(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} OpenGL::GLU)
+    endif()
+
+	target_compile_definitions(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} -DUSE_OPENGL)
+
+endmacro()
diff --git a/dev/a2-carsoccer/config.h.in b/dev/a2-carsoccer/config.h.in
new file mode 100644
index 0000000..bf66666
--- /dev/null
+++ b/dev/a2-carsoccer/config.h.in
@@ -0,0 +1,13 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+*/
+
+
+// The file config.h.in is processed by cmake to produce config.h.  This
+// replaces strings of the form "at"CMAKE_VARIABLE_NAME"at" with the value
+// of the corresponding cmake variable, allowing us to pass directory paths
+// and other information configured with cmake into our C++ code.
+
+
+#define DATA_DIR_BUILD "@DATA_DIR_BUILD@"
+#define DATA_DIR_INSTALL "@DATA_DIR_INSTALL@"
+
diff --git a/dev/a2-carsoccer/data/crowd.png b/dev/a2-carsoccer/data/crowd.png
new file mode 100644
index 0000000..e6f14f3
--- /dev/null
+++ b/dev/a2-carsoccer/data/crowd.png
diff --git a/dev/a2-carsoccer/data/crowd.psd b/dev/a2-carsoccer/data/crowd.psd
new file mode 100644
index 0000000..f16a761
--- /dev/null
+++ b/dev/a2-carsoccer/data/crowd.psd
diff --git a/dev/a2-carsoccer/data/pitch.png b/dev/a2-carsoccer/data/pitch.png
new file mode 100644
index 0000000..bf36a3f
--- /dev/null
+++ b/dev/a2-carsoccer/data/pitch.png
diff --git a/dev/a2-carsoccer/data/pitch.psd b/dev/a2-carsoccer/data/pitch.psd
new file mode 100644
index 0000000..04970c8
--- /dev/null
+++ b/dev/a2-carsoccer/data/pitch.psd
diff --git a/dev/a2-carsoccer/main.cc b/dev/a2-carsoccer/main.cc
new file mode 100644
index 0000000..cc6c086
--- /dev/null
+++ b/dev/a2-carsoccer/main.cc
@@ -0,0 +1,11 @@
+/** CSci-4611 Assignment 2:  Car Soccer
+ */
+
+
+#include "car_soccer.h"
+
+int main(int argc, const char *argv[]) {
+    CarSoccer app;
+    app.Run();
+    return 0;
+}
diff --git a/dev/texture-demo/.gitignore b/dev/texture-demo/.gitignore
new file mode 100644
index 0000000..dd1a9a8
--- /dev/null
+++ b/dev/texture-demo/.gitignore
@@ -0,0 +1,2 @@
+config.h
+build
diff --git a/dev/texture-demo/CMakeLists.txt b/dev/texture-demo/CMakeLists.txt
new file mode 100644
index 0000000..0c7fce9
--- /dev/null
+++ b/dev/texture-demo/CMakeLists.txt
@@ -0,0 +1,193 @@
+# Original Author(s) of this File: 
+#   Daniel Keefe, 2017, University of Minnesota
+#  
+# Author(s) of Significant Updates/Modifications to the File:
+#   ... 
+
+
+
+# You are encouraged to copy this example, move it outside of the MinGfx directory, and use
+# it as a starting point for your project.  When you do this, you'll have to edit the
+# following line as needed to point to the MinGfx install prefix used on your system.
+
+# !!!!!!!!!!!!! EDIT THE FOLLOWING LINE AS NEEDED !!!!!!!!!!!!! 
+list(APPEND CMAKE_PREFIX_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../build/install ../..)
+
+
+#### BASIC PROJECT SETUP ####
+
+project(example)
+
+# Using 3.9 to get a modern version of FindOpenGL.cmake
+cmake_minimum_required (VERSION 3.9) 
+
+# Dependencies that are auto-downloaded, built, and installed for you will go in the 
+# directory pointed to by the CMAKE_INSTALL_PREFIX.  It defaults to a location inside
+# the build directory.
+if (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT OR "${CMAKE_INSTALL_PREFIX}" STREQUAL "")
+    set (CMAKE_INSTALL_PREFIX "${CMAKE_BINARY_DIR}/install" CACHE PATH "default install path" FORCE )
+endif()
+
+# Add to paths cmake uses to search for scripts, modules, and config packages
+list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_INSTALL_PREFIX})
+list(INSERT CMAKE_PREFIX_PATH 0 ${CMAKE_INSTALL_PREFIX})
+
+include(MessageMacros)
+h1("Building ${PROJECT_NAME}")
+h2("Configuring paths")
+
+message(STATUS "Module path: ${CMAKE_MODULE_PATH}")
+message(STATUS "Prefix path: ${CMAKE_PREFIX_PATH}")
+message(STATUS "Install prefix: ${CMAKE_INSTALL_PREFIX}")
+
+set(DATA_DIR_BUILD ${CMAKE_CURRENT_SOURCE_DIR}/data)
+set(DATA_DIR_INSTALL ${CMAKE_INSTALL_PREFIX}/share/${PROJECT_NAME}/data)
+
+message(STATUS "Data dir (in build tree): ${DATA_DIR_BUILD}")
+message(STATUS "Data dir (in install tree): ${DATA_DIR_INSTALL}")
+
+set(SHADERS_DIR_BUILD ${CMAKE_CURRENT_SOURCE_DIR}/shaders)
+set(SHADERS_DIR_INSTALL ${CMAKE_INSTALL_PREFIX}/share/${PROJECT_NAME}/shaders)
+
+message(STATUS "Shaders dir (in build tree): ${SHADERS_DIR_BUILD}")
+message(STATUS "Shaders dir (in install tree): ${SHADERS_DIR_INSTALL}")
+
+
+# Configure a header file to pass some of the CMake settings to the source code
+configure_file(
+    ${CMAKE_CURRENT_SOURCE_DIR}/config.h.in
+    ${CMAKE_CURRENT_SOURCE_DIR}/config.h
+)
+
+
+#### SOURCE FOR THIS PROJECT ####
+h2("Configuring source files")
+
+set(SOURCEFILES
+    example.cc
+    main.cc
+)
+
+set(HEADERFILES
+    config.h
+    example.h
+)
+
+set(EXTRAFILES
+    README.md
+)
+
+set(SHADERFILES
+)
+
+set_source_files_properties(${EXTRAFILES} PROPERTIES HEADER_FILE_ONLY TRUE)
+set_source_files_properties(${SHADERFILES} PROPERTIES HEADER_FILE_ONLY TRUE)
+
+source_group("Shaders" FILES ${SHADERFILES})
+
+
+#### COMPILE OPTIONS ####
+
+h2("Configuring Compiler Options")
+
+
+
+message(STATUS "Building for " ${CMAKE_SYSTEM_NAME} ".")
+
+# Linux specific
+if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+  add_definitions(-DLINUX)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
+endif()
+
+
+# Apple specific
+if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  add_definitions(-DOSX)
+
+  # RPATH settings, see https://cmake.org/Wiki/CMake_RPATH_handling
+  set(CMAKE_MACOSX_RPATH ON)
+
+  # use, i.e. don't skip the full RPATH for the build tree
+  SET(CMAKE_SKIP_BUILD_RPATH  FALSE)
+
+  # when building, don't use the install RPATH already
+  # (but later on when installing)
+  SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE) 
+
+  SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
+
+  # add the automatically determined parts of the RPATH
+  # which point to directories outside the build tree to the install RPATH
+  SET(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+
+  # the RPATH to be used when installing, but only if it's not a system directory
+  LIST(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
+  IF("${isSystemDir}" STREQUAL "-1")
+     SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
+  ENDIF("${isSystemDir}" STREQUAL "-1")
+  
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
+endif()
+
+
+# Windows specific
+if (WIN32)
+  add_definitions(-DWIN32)
+
+  if(NOT CMAKE_SIZEOF_VOID_P EQUAL 8)
+    message(FATAL_ERROR
+        "You must use the 64 bit version of the compiler. Be sure to set the correct generator when configuring through CMake.")
+  endif()
+endif()
+
+
+
+
+
+#### DEFINE TARGET(S) ####
+
+h2("Defining Target(s)")
+
+add_executable(${PROJECT_NAME} ${SOURCEFILES} ${HEADERFILES} ${EXTRAFILES} ${SHADERFILES})
+
+
+
+#### FIND AND ADD DEPENDENCIES ####
+
+h2("Adding Dependencies")
+set(EXTERNAL_DIR external)
+
+
+# MinGfx (linked with an imported cmake target so no need to specify include dirs)
+# This will try to find MinGfxConfig.cmake, which should have been installed under
+# CMAKE_INSTALL_PREFIX/lib/cmake/MinGfx when you installed the MinGfx Toolkit.
+find_package(MinGfx REQUIRED)
+target_link_libraries(${PROJECT_NAME} PUBLIC MinGfx::MinGfx)
+
+
+# Add dependency on OpenGL
+include(UseOpenGL)
+UseOpenGL(${PROJECT_NAME} PUBLIC ${EXTERNAL_DIR})
+
+
+
+#### INSTALL TARGET(S) ####
+
+h2("Configuring Install Target")
+
+# The install locations are relative to the CMAKE_INSTALL_PREFIX variable
+install(TARGETS ${PROJECT_NAME} RUNTIME DESTINATION bin)
+
+install(
+    DIRECTORY data/
+    DESTINATION ${DATA_DIR_INSTALL}
+    OPTIONAL
+)
+
+install(
+    DIRECTORY shaders/
+    DESTINATION ${SHADERS_DIR_INSTALL}
+    OPTIONAL
+)
diff --git a/dev/texture-demo/README.md b/dev/texture-demo/README.md
new file mode 100644
index 0000000..ee42984
--- /dev/null
+++ b/dev/texture-demo/README.md
@@ -0,0 +1 @@
+# Angry Vectors CSci-4611 In-Class Example of Visual Debugging
diff --git a/dev/texture-demo/cmake/DownloadHelper.txt.in b/dev/texture-demo/cmake/DownloadHelper.txt.in
new file mode 100644
index 0000000..fb29bff
--- /dev/null
+++ b/dev/texture-demo/cmake/DownloadHelper.txt.in
@@ -0,0 +1,26 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+# This is a "helper" cmake project -- the only thing this project does is download
+# the external project.  So, the configure, build, install, and test commands for 
+# ExternalProject_Add() are intentionally set as NOPs.  
+
+cmake_minimum_required (VERSION 3.9) 
+
+project(@EXT_PROJECT_NAME@-download)
+
+include(ExternalProject)
+ExternalProject_Add(
+  @EXT_PROJECT_NAME@
+  SOURCE_DIR "@DOWNLOAD_DIR@/@EXT_PROJECT_NAME@/src"
+  BINARY_DIR "@DOWNLOAD_DIR@/@EXT_PROJECT_NAME@/download-helper"
+  @DOWNLOAD_OPTIONS@
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND ""
+  INSTALL_COMMAND ""
+  TEST_COMMAND ""
+  LOG_DOWNLOAD ON
+  GIT_PROGRESS 1
+)
+
+
diff --git a/dev/texture-demo/cmake/ExternalProjectDownloadBuildInstall.cmake b/dev/texture-demo/cmake/ExternalProjectDownloadBuildInstall.cmake
new file mode 100644
index 0000000..ce12d1d
--- /dev/null
+++ b/dev/texture-demo/cmake/ExternalProjectDownloadBuildInstall.cmake
@@ -0,0 +1,98 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+
+# Calling CMAKE_CURRENT_LIST_DIR inside a function returns the list dir of the calling script
+# but we want the list dir of this file in order to find the DownloadHelper.txt.in file, which
+# should be stored right next to this one.  So, defining this variable outside the scope of the
+# functions below.
+set(DIR_OF_THIS_FILE ${CMAKE_CURRENT_LIST_DIR})  
+
+
+
+# Usage:  
+# ExternalProject_Download(
+#     # This first argument is the name of the project to download.  It is required:
+#     glm
+#
+#     # Additional arguments specify how to download the project using GIT, SVN, CVS, or URL.
+#     # These can be any of the arguments used for the downloading step of the cmake builtin
+#     # ExternalProject_Add command. 
+#     GIT_REPOSITORY "https://github.com/g-truc/glm.git"
+#     GIT_TAG master
+#     etc..
+# )
+function(ExternalProject_Download EXT_PROJECT_NAME DOWNLOAD_DIR)
+
+    include(MessageMacros)
+    h1("BEGIN EXTERNAL PROJECT DOWNLOAD (${EXT_PROJECT_NAME}).")
+
+    h2("Creating a download helper project for ${EXT_PROJECT_NAME}.")
+
+    set(DOWNLOAD_OPTIONS ${ARGN})
+    string (REGEX REPLACE "(^|[^\\\\]);" "\\1 " DOWNLOAD_OPTIONS "${DOWNLOAD_OPTIONS}")
+
+
+    file(MAKE_DIRECTORY ${DOWNLOAD_DIR}/${EXT_PROJECT_NAME})
+    configure_file(
+        ${DIR_OF_THIS_FILE}/DownloadHelper.txt.in 
+        ${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper/CMakeLists.txt
+    )
+
+    h2("Generating build files for the ${EXT_PROJECT_NAME} download helper project.")
+    execute_process(COMMAND "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" . WORKING_DIRECTORY "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper")
+
+    h2("Building the ${EXT_PROJECT_NAME} download helper project.  (This actually performs the download and may take some time...)")
+    execute_process(COMMAND "${CMAKE_COMMAND}" --build . WORKING_DIRECTORY "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/download-helper")
+
+    h2("Completed download of external project ${EXT_PROJECT_NAME}.")
+
+endfunction()
+
+
+# Usage:  
+# ExternalProject_BuildAndInstallNow(
+#     # This first argument is the name of the external project to download.  It is required:
+#     VRPN
+#     # This second argument is the relative path from ${EXTERNAL_DIR_NAME}/projectname/ to the project's
+#     # main CMakeLists.txt file:
+#     src
+#
+#     # Additional arguments are passed on as options to the cmake build file generator
+#     -DVRPN_BUILD_DIRECTSHOW_VIDEO_SERVER=OFF
+#     -DVRPN_BUILD_HID_GUI=OFF
+#     etc..
+# )
+function(ExternalProject_BuildAndInstallNow EXT_PROJECT_NAME DOWNLOAD_DIR RELPATH_TO_CMAKELISTS)
+
+    include(MessageMacros)
+    h1("BEGIN EXTERNAL PROJECT BUILD AND INSTALL (${EXT_PROJECT_NAME}).")
+
+    # any extra args to the function are interpreted as arguments for the cmake config process
+    set(CMAKE_CONFIG_OPTIONS ${ARGN})
+
+    # always set the install prefix to be the same as for the main project
+    list(APPEND CMAKE_CONFIG_OPTIONS -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX})
+
+    #string (REGEX REPLACE "(^|[^\\\\]);" "\\1 " CMAKE_CONFIG_OPTIONS "${CMAKE_CONFIG_OPTIONS}")
+
+
+    set(SRC_DIR "${DOWNLOAD_DIR}/${EXT_PROJECT_NAME}/${RELPATH_TO_CMAKELISTS}")
+    set(BUILD_DIR "${CMAKE_BINARY_DIR}/external/${EXT_PROJECT_NAME}")
+
+    file(MAKE_DIRECTORY ${BUILD_DIR})
+
+    h2("Generating build files for external project ${EXT_PROJECT_NAME}.")
+    message(STATUS "Using source dir: ${SRC_DIR}")
+    message(STATUS "Using build dir: ${BUILD_DIR}")
+    message(STATUS "Config options: ${CMAKE_CONFIG_OPTIONS}")
+
+    execute_process(COMMAND "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" ${SRC_DIR} ${CMAKE_CONFIG_OPTIONS} WORKING_DIRECTORY ${BUILD_DIR})
+
+    h2("Building external project ${EXT_PROJECT_NAME}.  (This may take some time...)")
+    execute_process(COMMAND "${CMAKE_COMMAND}" --build ${BUILD_DIR} --target install)
+
+    h2("Completed external build of ${EXT_PROJECT_NAME}.")
+
+endfunction()
+
diff --git a/dev/texture-demo/cmake/MessageMacros.cmake b/dev/texture-demo/cmake/MessageMacros.cmake
new file mode 100644
index 0000000..4628e5c
--- /dev/null
+++ b/dev/texture-demo/cmake/MessageMacros.cmake
@@ -0,0 +1,17 @@
+# This file is part of the MinVR cmake build system.  
+# See the main MinVR/CMakeLists.txt file for authors, copyright, and license info.
+
+
+macro(h1 TITLE)
+  string(TOUPPER ${TITLE} TITLE)
+  message(STATUS "\n\n==== ${TITLE} ====")
+endmacro()
+
+macro(h2 TITLE)
+  message(STATUS "\n* ${TITLE}")
+endmacro()
+
+macro(h3 TITLE)
+  message(STATUS "- ${TITLE}")
+endmacro()
+
diff --git a/dev/texture-demo/cmake/UseOpenGL.cmake b/dev/texture-demo/cmake/UseOpenGL.cmake
new file mode 100644
index 0000000..2ec5ffb
--- /dev/null
+++ b/dev/texture-demo/cmake/UseOpenGL.cmake
@@ -0,0 +1,52 @@
+# This file is part of the MinGfx cmake build system.  
+# See the main MinGfx/CMakeLists.txt file for authors, copyright, and license info.
+
+# Either finds a pre-installed version or complains.
+
+# Usage: In your CMakeLists.txt, somewhere after you define the target that depends
+# on the OpenGL library (typical with something like add_executable(${PROJECT_NAME} ...) 
+# or add_library(${PROJECT_NAME} ...)), add the following two lines:
+
+#    include(UseOpenGL)
+#    UseOpenGL(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/external)
+
+# The second argument can be either PUBLIC, PRIVATE, or INTERFACE, following the keyword
+# usage described here: 
+# https://cmake.org/cmake/help/latest/command/target_include_directories.html
+
+# The third argument is the directory to use for downloading the external project if
+# autobuild is used.
+
+
+
+macro(UseOpenGL YOUR_TARGET INTERFACE_PUBLIC_OR_PRIVATE DOWNLOAD_DIR)
+
+    message(STATUS "Searching for OpenGL...")
+
+	# Check to see if the library is already installed on the system    
+    # CMake ships with FindOpenGL.cmake and in CMake 3.9+ it defines
+    # the imported targets OpenGL::GL and OpenGL::GLU.  Using these is
+    # now the preferred way to link with OpenGL and all of its dependencies.
+	# See https://cmake.org/cmake/help/v3.9/module/FindOpenGL.html
+	find_package(OpenGL)
+
+	if (NOT ${OPENGL_FOUND})
+	    message(FATAL_ERROR "OpenGL was not found on the system.  MinGfx can auto-download and build many dependencies for you, but not OpenGL. It should come pre-installed on your system.")
+	endif()
+
+    message(STATUS "Ok: OpenGL Found.")
+    message(STATUS "OpenGL headers: ${OPENGL_INCLUDE_DIR}")
+    message(STATUS "OpenGL libs: ${OPENGL_LIBRARIES}")
+
+
+    message(STATUS "Linking target ${YOUR_TARGET} with ${INTERFACE_PUBLIC_OR_PRIVATE} dependency OpenGL::GL.")
+    target_link_libraries(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} OpenGL::GL)
+
+    if (${OPENGL_GLU_FOUND})
+        message(STATUS "Linking target ${YOUR_TARGET} with ${INTERFACE_PUBLIC_OR_PRIVATE} dependency OpenGL::GLU.")
+        target_link_libraries(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} OpenGL::GLU)
+    endif()
+
+	target_compile_definitions(${YOUR_TARGET} ${INTERFACE_PUBLIC_OR_PRIVATE} -DUSE_OPENGL)
+
+endmacro()
diff --git a/dev/texture-demo/config.h.in b/dev/texture-demo/config.h.in
new file mode 100644
index 0000000..16d824b
--- /dev/null
+++ b/dev/texture-demo/config.h.in
@@ -0,0 +1,13 @@
+/** CSci-4611 In-Class Example
+*/
+
+
+// The file config.h.in is processed by cmake to produce config.h.  This
+// replaces strings of the form "at"CMAKE_VARIABLE_NAME"at" with the value
+// of the corresponding cmake variable, allowing us to pass directory paths
+// and other information configured with cmake into our C++ code.
+
+
+#define DATA_DIR_BUILD "@DATA_DIR_BUILD@"
+#define DATA_DIR_INSTALL "@DATA_DIR_INSTALL@"
+
diff --git a/dev/texture-demo/data/campbells.png b/dev/texture-demo/data/campbells.png
new file mode 100644
index 0000000..ed4b245
--- /dev/null
+++ b/dev/texture-demo/data/campbells.png
diff --git a/dev/texture-demo/data/monalisa.png b/dev/texture-demo/data/monalisa.png
new file mode 100644
index 0000000..91e5498
--- /dev/null
+++ b/dev/texture-demo/data/monalisa.png
diff --git a/dev/texture-demo/example.cc b/dev/texture-demo/example.cc
new file mode 100644
index 0000000..b114da5
--- /dev/null
+++ b/dev/texture-demo/example.cc
@@ -0,0 +1,113 @@
+/** CSci-4611 In-Class Example */
+
+#include "example.h"
+
+#include "config.h"
+
+#include <iostream>
+#include <sstream>
+
+
+
+Example::Example() : GraphicsApp(1024,768, "MinGfx Example") {
+    // Define a search path for finding data files (images and shaders)
+    search_path_.push_back(".");
+    search_path_.push_back("./data");
+    search_path_.push_back(DATA_DIR_INSTALL);
+    search_path_.push_back(DATA_DIR_BUILD);
+}
+
+
+Example::~Example() {
+}
+
+
+void Example::UpdateSimulation(double dt)  {
+}
+
+
+void Example::InitOpenGL() {
+    // Set up the camera in a good position to see the entire scene
+    proj_matrix_ = Matrix4::Perspective(60.0f, aspect_ratio(), 0.01f, 100.0f);
+    view_matrix_ = Matrix4::LookAt(Point3(2,1,4), Point3(2,1,0), Vector3(0,1,0));
+    glClearColor(1,1,1,1);
+    
+    
+    // Load the texture we will use
+    texture_.InitFromFile(Platform::FindFile("monalisa.png", search_path_));
+    
+     
+    // Create the mesh by setting the vertex and index arrays directly
+    std::vector<unsigned int> indices;
+    std::vector<Point3> vertices;
+    std::vector<Vector3> normals;
+    std::vector<Point2> tex_coords;
+    
+    // four vertices, each requires 3 floats: (x,y,z)
+    vertices.push_back(Point3(0,0,0));
+    vertices.push_back(Point3(1,0,0));
+    vertices.push_back(Point3(1,1,-1));
+    vertices.push_back(Point3(0,1,-1));
+    
+    // four normals, each requires 3 floats: (x,y,z)
+    normals.push_back(Vector3(0,1,1).ToUnit());
+    normals.push_back(Vector3(0,1,1).ToUnit());
+    normals.push_back(Vector3(0,1,1).ToUnit());
+    normals.push_back(Vector3(0,1,1).ToUnit());
+    
+    // TODO: YOU ADD TEXTURE COORDINATES TO THE MESH
+
+    
+    
+    // indices into the arrays above for the first triangle
+    indices.push_back(0);
+    indices.push_back(1);
+    indices.push_back(2);
+    
+    // indices for the second triangle, note some are reused
+    indices.push_back(0);
+    indices.push_back(2);
+    indices.push_back(3);
+    
+    mesh_.SetVertices(vertices);
+    mesh_.SetNormals(normals);
+    mesh_.SetIndices(indices);
+    
+    // TODO: ALSO REMEMBER TO CALL mesh_.SetTexCoords(..) HERE ONCE YOU HAVE THEM DEFINED.
+    // USE TEXTURE UNIT = 0 SINCE WE HAVE ONLY ONE TEXTURE APPLIED TO THE MESH.
+    
+    mesh_.UpdateGPUMemory();
+    
+}
+
+
+void Example::DrawUsingOpenGL() {
+    // draws a set of axes at the world origin, since we are passing the identity
+    // matrix for the "model" matrix.
+    Matrix4 identity;
+    quick_shapes_.DrawAxes(identity, view_matrix_, proj_matrix_);
+    
+    
+    // We're already learned about how to use transformation matrices to move
+    // an individual model around within the scene.
+    Matrix4 model_matrix = Matrix4::Scale(Vector3(4,4,4));
+
+    
+    // Since we want to texture the mesh we will define a custom material for the
+    // mesh.  The material property we are interested in is called "surface_texture".
+    // We'll set that to point to the Texture2D that we loaded earlier.  You can
+    // also set other properties of the material to define how it reflects light.
+    DefaultShader::MaterialProperties mesh_material;
+    mesh_material.surface_texture = texture_;
+    mesh_material.ambient_reflectance = Color(0.8f, 0.8f, 0.8f);
+    mesh_material.diffuse_reflectance = Color(0.8f, 0.8f, 0.8f);
+    
+    
+    // Use a shader program to draw the mesh with the given model, view, and projection
+    // matrices and with the material properties defined in mesh_material.
+    shader_.Draw(model_matrix, view_matrix_, proj_matrix_, &mesh_, mesh_material);
+}
+
+
+
+
diff --git a/dev/texture-demo/example.h b/dev/texture-demo/example.h
new file mode 100644
index 0000000..afecff6
--- /dev/null
+++ b/dev/texture-demo/example.h
@@ -0,0 +1,65 @@
+/** CSci-4611 In-Class Example */
+
+#ifndef SNOWMAN_H_
+#define SNOWMAN_H_
+
+#include <mingfx.h>
+using namespace mingfx;
+
+#include <string>
+#include <vector>
+
+class Example : public GraphicsApp {
+public:
+  
+    // Creates the App
+    Example();
+    
+    // Cleans up when the App shuts down
+    virtual ~Example();
+    
+    // Note a Run() function is inherited from GraphicsApp, that's what
+    // actually starts up the App.
+    
+    // This is a callback, a function that gets called when the user presses
+    // the Pause button in the GUI.
+    void OnPauseBtnPressed();
+    
+    // This gets called once each frame.  Note that dt (a.k.a., "delta time") is
+    // the amount of time (in seconds) that has passed since the last frame.
+    void UpdateSimulation(double dt);
+    
+    // This is where we initialize any OpenGL data, like textures or meshes that
+    // need to be loaded from files and setup in OpenGL.  It gets called once
+    // when the program starts up.
+    void InitOpenGL();
+    
+    // This gets called once each frame, and this is where you draw the latest
+    // version of your 3D graphics scene.
+    void DrawUsingOpenGL();
+    
+    
+private:
+
+    // Texture loaded from a file
+    Texture2D texture_;
+    
+    // Triangle mesh data structure
+    Mesh mesh_;
+
+    // A shader is required to draw meshes, MinGfx provides a default shader
+    // that does some simple lighting.
+    DefaultShader shader_;
+    
+    // Sets up the computer graphics camera
+    Matrix4 view_matrix_;
+    Matrix4 proj_matrix_;
+    
+    // A helper class for drawing some simple shapes (cubes, spheres, 3D arrows)
+    QuickShapes quick_shapes_;
+    
+    // Paths to search for data files, like images
+    std::vector<std::string> search_path_;
+};
+
+#endif
\ No newline at end of file
diff --git a/dev/texture-demo/main.cc b/dev/texture-demo/main.cc
new file mode 100644
index 0000000..3bbc8b8
--- /dev/null
+++ b/dev/texture-demo/main.cc
@@ -0,0 +1,9 @@
+/** CSci-4611 In-Class Example */
+
+#include "example.h"
+
+int main(int argc, const char *argv[]) {
+    Example app;
+    app.Run();
+    return 0;
+}
diff --git a/worksheets/a2_carsoccer.md b/worksheets/a2_carsoccer.md
new file mode 100644
index 0000000..95170c4
--- /dev/null
+++ b/worksheets/a2_carsoccer.md
@@ -0,0 +1,156 @@
+# Assignment 2 (Car Soccer) Worksheet
+
+## Definitions
+
+Use the following C++ style pseudocode definitions for Q1 and Q2:
+
+```
+/* Use this Point3 class to store x,y,z values that define a mathematical
+ * point (i.e., a position) in 3-space.
+ */
+class Point3 {
+    float x;
+    float y;
+    float z;
+};
+
+/* Use this Vector3 class to store x,y,z values that define a vector in
+ * 3-space.  Remember, mathematically, a vector is quite different than
+ * a point.  It has a direction and a magnitude but no position!
+ * For vectors it is often useful to be able to compute the length,
+ * also known as the magnitude, of the vector.
+ */
+class Vector3  {
+    float x;
+    float y;
+    float z;
+    
+    // returns the length (i.e., magnitude) of the vector
+    float Length() {
+        return sqrt(x*x + y*y + z*z);
+    }
+};
+
+
+/* In C++ and other languages we can define operators so we can use
+ * the +, -, =, *, / operations on custom classes.  Like many graphics
+ * libraries, this is what MinGfx does to make it easy to work with
+ * points and vectors in code.  For example, recall from class that
+ * if we have a point A (Coffman Union) and we add a vector (direction
+ * and magnitude) to this, we arrive at a new point B (e.g., Murphy Hall).
+ * Conceptually, a point + a vector = a new point.  Mathematically, it
+ * does not make sense to add two points, but it does make sense to 
+ * subtract two points.  The "difference" between the Murphy and Coffman 
+ * points is a vector that tells us the direction and magnitude we would
+ * need to walk from Coffman to get to Murphy.  Here's how we can write
+ * that in code using Point3, Vector3, and operators like + and -.
+ *
+ *   Point3 murphy = Point3(5, 8, 0);
+ *   Point3 coffman = Point3(4, 6, 0);
+ *   Vector3 toMurphy = murphy - coffman; 
+ *
+ *   // or, if we were given coffman and toMurphy we could find
+ *   // the point "murphy" by starting at point "coffman" and adding
+ *   // the vector "toMurphy".
+ *   Point3 murphy2 = coffman + toMurhpy; 
+ *
+ * The code that defines these opertors looks something like this:
+*/
+
+// a point + a vector = a new point
+Point3 operator+(Point3 p, Vector3 v) { 
+   return Point3(p.x + v.x, p.y + v.y, p.z + v.z); 
+}
+
+// a point - a point = a vector 
+// the dir and magnitude needed to go from point point B to point A
+Vector3 operator-(Point3 A, Point3 B) {
+    return Vector3(A.x - B.x, A.y - B.y, A.z - B.z);
+}
+
+// a vector * a scalar = a new vector with scaled magnitude
+Vector3 operator*(Vector3 v, float s) {
+    return Vector3(v.x * s, v.y * s, v.z * s);
+}
+
+
+
+/* Given all these tools, we can define additional classes for geometries
+ * that are useful in graphics.  For example, we can represent a sphere
+ * using a Point3 for the position of the center point of the sphere and
+ * a float for the sphere's radius.
+ */
+class Sphere {
+    Point3 position;
+    float radius;
+};
+```
+
+## Q1: Eulerian Integration
+
+In computer graphics and animation, there are many forms of integration that
+are used. For simple physics models like we have in Car Soccer, Eulerian
+Integration is good enough. Eulerian Integration uses velocity and position
+information from the current frame, and the elapsed time to produce a position
+for the next frame. Write pseudocode for determining the position of the sphere in the
+next frame:
+
+*Hint: think back to the motion equations from introductory physics. Or, look
+around in the assignment handout.*
+
+```
+Vector3 velocity = Vector3(1.0, 1.0, 1.0);
+float dt = 20; // milliseconds
+
+Sphere s = Sphere {
+    position: Point3(0.0, 0.0, 0.0),
+    radius: 5.0,
+};
+
+s.position = /* --- Fill in the next frame position computation here --- */
+```
+
+
+
+## Q2: Sphere Intersection
+
+In this assignment, you will need to test intersections between spheres and
+other objects. Using the information contained within each sphere class,
+write pseudocode to determine whether or not two spheres are intersecting
+(which you can use for car/ball intersections):
+
+```
+bool sphereIntersection(Sphere s1, Sphere s2) {
+    /* --- Fill in your sphere intersection code here --- */
+    
+
+}
+```
+
+To check that your intersections work, try working through the math by hand for the
+following two cases.  You can write out the math on a scrap piece of paper.   You do
+not need to include that detail in this worksheet.  But, do change the lines below where
+it says "Fill in expected output" to indicate whether True or False would be returned:
+
+```
+Sphere s1 = Sphere {
+    position: Point3(0.0, 1.0, 0.0),
+    radius: 1.0,
+};
+
+Sphere s2 = Sphere {
+    position: Point3(3.0, 0.0, 0.0),
+    radius: 1.0,
+};
+
+Sphere s3 = Sphere {
+    position: Point3(1.0, 1.0, 0.0),
+    radius: 2.0,
+};
+
+print(sphereIntersection(s1, s2));
+/* --- Fill in expected output (True or False) --- */
+
+print(sphereIntersection(s1, s3));
+/* --- Fill in expected output (True or False) --- */
+```