Canvas Backend Design

Responsibilities

• Consume the same backend-neutral DrawList as the TUI backend.
• Reuse the frontend perspective-correct software Z-buffer.
• Convert visible luma values to quantized RGB shades.
• Merge adjacent equal-shade pixels into horizontal Canvas fill runs.

Boundary

The package is JS-only and owns browser Canvas details. Core, view, and frontend do not depend on DOM types. demo_canvas owns element lookup, animation frames, and demo selection.

Limitations

Rendering is opaque and uses one foreground RGB color scaled by luma. There are no materials, textures, alpha blending, anti-aliasing, or GPU acceleration.