ztoadz / MTR

this is a toy project to play around with Zig in a real-time graphics context.

to test: zig test tests/package.zig -lc -lOpenCL --main-pkg-path .

there are currently 4 or so projects here

• compute rendering backend 'mtr'
• 'toy' application
• model loading library/format
• model converter

This exists as both a rendering backend 'MTR' (Monte Toad Renderer), as well as a front-end renderering application. The rendering backend is meant to be implementable for any graphics API backend (vulkan, directx, etc), but the current rendering backend supports just Vulkan.

This is a compute-based rendering pipeline, and as such no use of the rasterization pipeline is used (at least for now). A lot of inspiration is taken from nvidia's mesh shaders and ue5's nanite.

The rendering pipeline looks like

Mesh assembler

User can fetch attributes from storage buffers and emit them to an intermediary buffer, which selects how the triangle will be rasterized (micro-rasterizer or tile-based rasterizer).

Microrasterizer

Nanite UE5 style rendering. One thread per triangle, iterates the bounds of the triangle like traditional scanline rasterization. This renders to a visibility buffer with imageAtomicMax.

Tile based rasterizer

Screen is split into 16x16 bins and triangles are placed into them if they are too large for the micro-rasterizer. Instead of iterating the bounds of the triangle, the tile is iterated through. Also renders to the same visibility buffer.

Material shader

Renders the material of the primitives as fragments, by using the depth and triangle ID stored in visibility buffer to recompute barycentric UV coords.

Goals to experiment with:

• MSAA with visibility/deferred rendering
• Debug interface over Vk