GPU Programming Lab 4: Tessellation with Squares

Due Monday, September 26

Last Wednesday, the in-class demo on tessellation shaders used triangles for subdivision. This is fine, but for a cube, perhaps it would be more natural to define the cube using quads, and subdivide into triangles using tessellation.
For this week's lab, modify the tessellation demo so that it uses quads instead of triangles. You'll have to change the cube element list into quads, change the patch side to 4, and make a number of changes on both the tcs and tes. Refer to khronos and figure out what changes you'll need, but it summarizes as dividing squares instead of triangles.
I expect the biggest hangup will be mixing the 4 vertices from the square to find the 3D coordinates of each vertex. Remember that when using quads, only the first two tessellation coordinates are significant, and they indicate coordinates within the square.