pavel/editor
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
editor/docs/shader-toolchain.md
pavel 8d85568713 Embed compiled SPIR-V shaders in the client binary with #load 
The GPU renderer previously read .spv files from a cwd-relative path at
runtime; when they were missing or the editor was launched from outside
the repo root, it silently fell back to the SDL renderer, losing syntax
highlighting. The shaders are now baked in at compile time, so the
binary is self-contained. The compiled .spv files are committed (no
longer gitignored) since they are required to build; regenerate with
scripts/compile-shaders.sh after editing the GLSL sources.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-03 09:22:17 +02:00

1.6 KiB
Raw Permalink Blame History

SDL3 GPU Shader Toolchain

SDL3 GPU accepts different shader formats depending on the selected backend:

  • Vulkan: SPIR-V
  • D3D12: DXBC or DXIL
  • Metal: MSL or metallib

For this Linux-first prototype, use GLSL compiled to SPIR-V with glslc from shaderc.

scripts/compile-shaders.sh

Outputs are written to client/odin/shaders/compiled/ and are committed to git: the Odin client embeds them at compile time with #load, so they must exist to build. After editing the GLSL sources, rerun the script and rebuild the client.

Fedora install:

sudo dnf install glslc

Cross-platform path later:

  • Use SDL_shadercross for offline conversion from SPIR-V or HLSL to backend-specific shader formats.
  • Keep source shaders in git.
  • Generate SPIR-V/DXIL/MSL in CI or release packaging.
  • At runtime, choose the shader blob matching SDL.GetGPUDeviceDriver(device) or SDL.GetGPUShaderFormats(device).

Current recommendation:

  • Build Linux/Vulkan first with checked-in GLSL sources and generated SPIR-V as build artifacts.
  • Add SDL_shadercross only when Windows/macOS backends matter.

Current renderer state:

  • The editor embeds rect.vert.spv and rect.frag.spv for the direct SDL3 GPU path.
  • The editor embeds text.vert.spv and text.frag.spv for font-atlas text.
  • The binary has no runtime dependency on the shader files; they are baked in at build time.
  • Text is rendered from a baked stb_truetype atlas using /usr/share/fonts/google-noto/NotoSansMono-Regular.ttf.
  • A later portability step should bundle a project font or add configurable font discovery.