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+# Assignment 1 (Text Rain) Worksheet
+
+For the conceptual worksheets in this course, we'll provide a Markdown
+template from the shared-upstream repository. As described in the Canvas
+assignment handouts, you'll pull each Markdown template into your repository,
+directly edit your local copy with your answers, and commit and push your
+answers to GitHub in your `worksheets` folder of your repository. If you're
+unfamiliar with Markdown syntax, [check out this lovely guide provided by
+GitHub](https://guides.github.com/features/mastering-markdown/) before you get
+started.
+
+_Do not make a copy of the provided Markdown template and submit that instead._
+Our grading scripts will be looking for these modified files within your
+`worksheets` folder of your repository. Do not change the filenames, simply
+modify the contents.
+
+## Background
+
+By default, Processing uses the integer-based `0-255` convention to represent
+colors. For instance, bright, full-saturation red is represented as
+`color(255, 0, 0)`.  Processing also supports grayscale colors; black is
+`color(0)` and white is `color(255)`. You may wish to look at the [color class
+documentation](https://processing.org/reference/color_.html) and/or the
+[tutorial explaining color in
+Processing](https://processing.org/tutorials/color/).
+
+
+## Q1: Indexing
+
+As mentioned in the assignment handout, accessing/setting pixel data via
+Processing's `get()` and `set()` routines is a bit easier to code, but it's
+much slower than directly accessing/changing a [PImage
+object's](https://processing.org/reference/PImage.html) `pixels[]` array.
+Processing stores a 2D image in this 1D array, so getting the proper pixel out
+requires a little additional math.
+
+In the code block below, write the equation for obtaining the index in the 1D
+array from a (row, column) in the 2D pixels array. Keep in mind you can use
+information from `inputImg` to help you.
+
+```
+PImage inputImg = loadImage("test.jpg");
+
+int index1D = /* --- Fill this in --- */;
+```
+
+
+## Q2: Thresholding
+
+The image processing technique known as *thresholding* will be useful while
+creating your Text Rain. During the thresholding operation, if a pixel's
+grayscale value is less than `threshold`, then it becomes black. If the
+value is greater than `threshold`, it becomes white. You can use the green
+channel of the color as the grayscale value.
+
+In the code block below, write a Java code snippet for thresholding one pixel
+(`inputPixel`) to black or white.
+
+```java
+final int threshold = 128;
+
+// Returns: thresholded color (black or white)
+color thresholdPixel(color inputPixel) {
+
+  /* --- Fill this in --- */
+
+}
+```