The Graphics Pipeline

Give every point a fourth coordinate so one matrix can slide it, turn it, and show it in perspective, then divide by w and watch the far edge shrink.

Build a camera from two matrices: look-at moves the world in front of the eye, perspective squeezes it into a frame, and the near plane decides what is too close to draw.

Run a small program once per vertex, alone: read its attributes and the shared uniforms, move it, transform it to clip space, and hand on the varyings the next stage will blend.

Turn three corners into the pixels between them: an edge function per side, a bounding box to loop over, three signs per sample, and weights that add up to one.

Run a small program once per covered pixel: blend the corners' varyings by the pixel's weights, turn them into an intensity, and write it into the framebuffer.

Draw the scene from the light, keep the nearest depth per texel, then ask every pixel whether it lies deeper than the map says. A bias against acne, and the edge a coarse map leaves behind.