1 files changed, 185 insertions, 0 deletions
diff --git a/dev/MinGfx/src/vector2.cc b/dev/MinGfx/src/vector2.cc
new file mode 100644
index 0000000..cada189
--- /dev/null
+++ b/dev/MinGfx/src/vector2.cc
@@ -0,0 +1,185 @@
+/*
+ Copyright (c) 2017,2018 Regents of the University of Minnesota.
+ All Rights Reserved.
+ See corresponding header file for details.
+ */
+
+#include "vector2.h"
+
+#include <math.h>
+
+namespace mingfx {
+    
+    
+static const Vector2 s_zerov2d = Vector2(0,0);
+static const Vector2 s_onev2d = Vector2(1,1);
+static const Vector2 s_unitxv2d = Vector2(1,0);
+static const Vector2 s_unityv2d = Vector2(0,1);
+
+const Vector2& Vector2::Zero() { return s_zerov2d; }
+const Vector2& Vector2::One() { return s_onev2d; }
+const Vector2& Vector2::UnitX() { return s_unitxv2d; }
+const Vector2& Vector2::UnitY() { return s_unityv2d; }
+
+Vector2::Vector2() {
+    v[0] = 0.0;
+    v[1] = 0.0;
+}
+
+Vector2::Vector2(float x, float y) {
+    v[0] = x;
+    v[1] = y;
+}
+
+Vector2::Vector2(float *ptr) {
+    v[0] = ptr[0];
+    v[1] = ptr[1];
+}
+
+Vector2::Vector2(const Vector2& other) {
+    v[0] = other[0];
+    v[1] = other[1];
+}
+
+Vector2::~Vector2() {
+}
+
+bool Vector2::operator==(const Vector2& other) const {
+    return (fabs(other[0] - v[0]) < MINGFX_MATH_EPSILON &&
+            fabs(other[1] - v[1]) < MINGFX_MATH_EPSILON);
+}
+
+bool Vector2::operator!=(const Vector2& other) const {
+    return (fabs(other[0] - v[0]) >= MINGFX_MATH_EPSILON &&
+            fabs(other[1] - v[1]) >= MINGFX_MATH_EPSILON);
+}
+
+Vector2& Vector2::operator=(const Vector2& other) {
+    v[0] = other[0];
+    v[1] = other[1];
+    return *this;
+}
+
+float Vector2::operator[](const int i) const {
+    if ((i>=0) && (i<=1)) {
+        return v[i];
+    }
+    else {
+        // w component of a vector is 0 so return the constant 0.0
+        return 0.0;
+    }
+}
+
+float& Vector2::operator[](const int i) {
+    return v[i];
+}
+
+float Vector2::Dot(const Vector2& other) const {
+    return v[0]*other[0] + v[1]*other[1];
+}
+
+float Vector2::Length() const {
+    return sqrt(v[0]*v[0] + v[1]*v[1]);
+}
+
+void Vector2::Normalize() {
+    // Hill & Kelley provide this:
+    float sizeSq =  + v[0]*v[0] + v[1]*v[1];
+    if (sizeSq < MINGFX_MATH_EPSILON) {
+        return; // do nothing to zero vectors;
+    }
+    float scaleFactor = (float)1.0/(float)sqrt(sizeSq);
+    v[0] *= scaleFactor;
+    v[1] *= scaleFactor;
+}
+
+Vector2 Vector2::ToUnit() const {
+    Vector2 v(*this);
+    v.Normalize();
+    return v;
+}
+
+
+Vector2 Vector2::Lerp(const Vector2 &b, float alpha) const {
+    float x = (1.0f-alpha)*(*this)[0] + alpha*b[0];
+    float y = (1.0f-alpha)*(*this)[1] + alpha*b[1];
+    return Vector2(x,y);
+}
+
+Vector2 Vector2::Lerp(const Vector2 &a, const Vector2 &b, float alpha) {
+    float x = (1.0f-alpha)*a[0] + alpha*b[0];
+    float y = (1.0f-alpha)*a[1] + alpha*b[1];
+    return Vector2(x,y);
+}
+
+    
+const float * Vector2::value_ptr() const {
+    return v;
+}
+
+    
+Vector2 Vector2::Normalize(const Vector2 &v) {
+    return v.ToUnit();
+}
+
+
+float Vector2::Dot(const Vector2 &v1, const Vector2 &v2) {
+    return v1.Dot(v2);
+}
+    
+
+
+Vector2 operator/(const Vector2& v, const float s) {
+    const float invS = 1 / s;
+    return Vector2(v[0]*invS, v[1]*invS);
+}
+
+Vector2 operator*(const float s, const Vector2& v) {
+    return Vector2(v[0]*s, v[1]*s);
+}
+
+Vector2 operator*(const Vector2& v, const float s) {
+    return Vector2(v[0]*s, v[1]*s);
+}
+
+Vector2 operator-(const Vector2& v) {
+    return Vector2(-v[0], -v[1]);
+}
+
+Point2 operator+(const Vector2& v, const Point2& p) {
+    return Point2(p[0] + v[0], p[1] + v[1]);
+};
+
+Point2 operator+(const Point2& p, const Vector2& v) {
+    return Point2(p[0] + v[0], p[1] + v[1]);
+}
+
+Vector2 operator+(const Vector2& v1, const Vector2& v2) {
+    return Vector2(v1[0] + v2[0], v1[1] + v2[1]);
+}
+
+Point2 operator-(const Point2& p, const Vector2& v) {
+    return Point2(p[0] - v[0], p[1] - v[1]);
+}
+
+Vector2 operator-(const Vector2& v1, const Vector2& v2) {
+    return Vector2(v1[0] - v2[0], v1[1] - v2[1]);
+}
+
+Vector2 operator-(const Point2& p1, const Point2& p2) {
+    return Vector2(p1[0] - p2[0], p1[1] - p2[1]);
+}
+
+
+std::ostream & operator<< ( std::ostream &os, const Vector2 &v) {
+    return os << "<" << v[0] << ", " << v[1] << ">";
+}
+
+std::istream & operator>> ( std::istream &is, Vector2 &v) {
+    // format:  <x, y, z>
+    char dummy;
+    return is >> dummy >> v[0] >> dummy >> v[1] >> dummy;
+}
+
+    
+} // end namespace