FreeBSD's CI VM (Mesa llvmpipe over GL) failed 22 effectcraft-gpu tests:
- Advanced 3D's camera-depth target was R32Float, which GLES can't render to without
EXT_color_buffer_float: create_render_pipeline failed validation (release builds only log
that and draw nothing). The target is now R32Uint holding the f32 bits (renderable on every
backend, lossless), and GpuContext checks the adapter's format features (render attachment,
blendable colour) and independent blending up front; when they're missing the render
pipelines are never built and Advanced 3D renders on the CPU.
- Signed `%` in the shaders: naga emits GLSL `%`, undefined for negative operands, which broke
the VR effects' horizontal wrap and Cell Pattern's tiling. A shared `imod` never takes `%` of
a negative number.
- asin/acos: Mesa's are coarse approximations (~1e-4 rad), visible in every lens/sphere/cylinder
mapping. `asin_p`/`acos_p` (Cephes' asinf polynomial) are f32-accurate on every backend.
- "Could not lock adapter context": the GL backend has one context lock per adapter with a
timeout, so tests driving devices concurrently panic. Every gpu test helper that hands out a
device holds one process-wide lock for the calling test; ui_web_job_gpu's two device tests
share a lock too.
- On GL, up to 1 % of pixels may flip across a decision boundary (division through a
reciprocal, unfused fma); the GPU-vs-CPU comparisons allow that there only.
Also adds the FreeBSD workflow (from the FreeBSD CI PR) so this branch is checked there.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
6eedf8e2c5