You'll be happy to know that the assignment due Oct 24 consists of a fun excursion into learning how to use a frame buffer. Once you have that under your belt, next week we will dive into implementing the rendering pipeline. Meanwhile, a complete outline of the rendering pipeline is below. I encourage you to study it.

THE RENDERING PIPELINE

As we discussed in class, the complete rendering pipeline will look something like the following outline. There are a number of variations possible. For example, the shading step can take place over various points - from vertex shading that we have below, to pixel shading, more expensive but more powerful, in which shading is done later in the pipeline.

Note that you are now doing a complete implementation of the window transform, which consists of the combination of your camera transform and your perspective transform.

• Start with a collection of objects
• Describe each object as a collection of triangles
• For each animation frame:
  • Clear the zbuffer by filling it with zeroes.
  • Transform the camera matrix C
  • For each object:
    • Transform the object by matrix M
    • Multiply inverse camera matrix and object matrix T = (C^-1M)
    • For each triangle of the object:
      • Transform each vertex of triangle by T
      • Clip the triangle to get a (possibly null) collection of triangles
      • For each of these triangles:
        • Do shading on each vertex, to define [r,g,b] for that vertex
        • Apply perspective transform to each vertex [x,y,z] → [-xf/z,-yf/z,-f/z]
        • Apply viewport transform to each vertex to get [px,py,pz]
        • Vertically split the triangle into two trapezoids
        • For each of these two trapezoids:
          • Loop through all scan lines from top to bottom
          • At each scan line:
            • Interpolate to get [px,r,g,b,pz] at left edge and at right edge
            • Loop through pixels from px_L to px_R
            • At each pixel, where we now have [r,g,b,pz]:
              • if pz > zbuffer[px][py]:
                • set zbuffer[px][py] to pz
                • set framebuffer[px][py] to r,g,b