@cImport is going to disappear in Zig 0.17. Its deprecated in Zig 0.16.
Let's remove it now.
Replace @cImport with addTranslateC across pkg/ packages. Each
package now has a c_import.h header that is translated at build
time via addTranslateC and exposed as a "cimport" module import.
Converted packages:
- dcimgui
- fontconfig
- freetype
- glslang
- harfbuzz
- macos
- oniguruma
- opengl
- sentry
- spirv-cross
- wuffs
Omitted:
- gtk4-layer-shell - This has a bit more complexity with how it
interacts with GTK headers, so I need to consider this a bit more.
- src/ - It'll be cleaner to do this separately.
The GLSL to MSL conversion process uses a passed-in sampler state for
the `iChannel0` parameter and we weren't providing it. This magically
worked on Apple Silicon for unknown reasons but failed on Intel GPUs.
In normal, hand-written MSL, we'd explicitly create the sampler state as
a normal variable (we do this in `shaders.metal` already!), but the
Shadertoy conversion stuff doesn't do this, probably because the exact
sampler parameters can't be safely known.
This fixes a Metal validation error when using custom shaders:
```
-[MTLDebugRenderCommandEncoder validateCommonDrawErrors:]:5970: failed
assertion `Draw Errors Validation Fragment Function(main0): missing Sampler
binding at index 0 for iChannel0Smplr[0].
```
