2-D Transformations and the 2-D viewing pipeline - Writeup
Phil Katz and Stephen St.Vincent
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Lab description


Lab summary:

In this lab, we created a matrix framework through which we will be able to manipulate graphical objects and viewpoints. This portion consisted only of creating the ability to instantiate matrices and manipulate them (clear, set to identity, scale, rotate, etc), as well as providing helper functions to apply these matrices to the various graphical elements that we've created (polygons, circles, points, etc).

For the next part of the assigment, we created a model of the Starship Enterprise using only a unit circle, and unit square, and matrix transformations.

Next, we thoroughly studied the sine and cosine functions in order to create a series of images depicting our Starship orbiting a star.

Finally, we created a view transformation matrix and made a series of images of the above scenario as viewed by a passing observer.

Questions:
  1. Who did you work with on this assignment, and what tasks did each of you do?
    Phil and Steve worked together. Steve produced most of the code, while Phil produced most of the plays performed at Swarthmore this weekend. Parts 1, 3, and 4 were actually a joint effort, though. Just not part 2.

  2. Describe the mechanism you developed for handling the global transformation parameters and matrix.
    We did not create any sort of structure for parts of an object, and as such were forced to multiply the GTM and the LTM for each part of the Starship. The parameters for the GTM only had to be adjusted in one place, though, due to our utter mastery of the overly-complex sine and cosine functions.

  3. Describe the mechanism you developed for handling the viewing pipeline parameters and transformation matrix.
    Similar to the GTM, we only had to create the VTM once, but had to multiply the VTM, GTM, and LTM before drawing each part of the Starship.

  4. Once you had the code in place, what was the process and how difficult was it to modify the view window and the position of the Enterprise?
    Changing the view window was the easist thing we've ever done. All we had to do was adjust the boundary points. The enterprise was a little more difficult in that we had to apply the GTM to every part of the ship individually, but once we had that code in place this part was also supremely trivial.

This was Bruce's first test image.


This is the second required image.


This is the third required image.


This is the fourth required image.