The testbed will currently display a 640x480 tiled texture of configurable size.
Things will change frequently. This is just a brainstorming page...
The Broccoli PPU has two 320x240 framebuffers. 9-bit pixels with 3-bit channels.
The Broccoli picture processor is a 2D sprite-based powerhouse.
Each texture cell will compute X/Y pixel/coordinate data based on a matrix and a power-of-2 square (RTL defines it, 32x and 128x are examples) 8-bit pixel memory.
The texture cells and write framebuffer can be manipulated procedurally by a pixel equation. The specifics will be decided on later.