psxboot

Mode 0 — Color Gradient
A full-screen animated color gradient. Each frame the draw environment's background RGB is cycled using setRGB0(), producing a smoothly shifting hue across the screen without any geometry submission.

Mode 1 — Starfield (Tile-Based)
Ten stars at fixed pseudo-random positions (seeded with a constant) rendered as cross-shaped TILE primitives. A global brightness value oscillates each frame based on the frame counter, applied uniformly to all star arms via setRGB0(). Demonstrates GPU TILE primitive usage and simple frame-driven animation.

Mode 2 — Sierpinski Pyramid
A 3D tetrahedron where each visible face is a recursively subdivided Sierpinski triangle rendered with filled POLY_F3 primitives. The pyramid rotates around all three axes using GTE RotMatrix / TransMatrix. Back-face culling via gte_nclip() and depth sorting via gte_avsz3() feed the ordering table. Recursion depth is hardcoded to 3.

Mode 3 — Solid Color
A static cornflower-blue background (the default draw environment color). Serves as a baseline "no animation" mode.