* Normally we want to inherit CC and CXX from the parent process to ensure that
the user's choice of compiler is respected. Unfortunately macOS 10.14 starts
shipping broken compilers, so inheriting CC & CXX causes the swig compilation
to fail.
* As a workaround, we just disable this on macOS assuming the user won't ever
want to override CC & CXX because it's all locked into XCode anyway.
* For some reason the actual paint event never makes it through after converting
to metal-compatible widgets, but painting in response to UpdateRequest (which
should become a paint really) works about as well.
* This isn't a real bug, it only happens temporarily during first show of a
window while the geometry is all messed up, but it causes some error spam in
the log so it's better to fix.
* Instead of just configuring SPIR-V disassemblers and picking only the first
one when we need to edit SPIR-V, we allow setting up any shader processor that
goes between two shader encodings.
* When editing, the default will still be to use embedded source, and then after
that the first tool that goes from the native shader format to a text format,
but the drop-down allows you to pick any of them.
* Similarly in the shader viewer you can configure the compilation options and
method, to choose the compiler you want to use. Embedded command line
parameters in the shader are automatically appended.
* This means e.g. the D3D11 back-end can accept DXBC directly if the UI can
provide it, or compile from HLSL as before.
* More importantly, the Vulkan back-end can take SPIR-V compiled from any
source, or compile from GLSL as before as a fall-back.
* This will allow the backend to specify both the native format (e.g. SPIR-V,
DXBC) as well as a language it might be able to internally compile (GLSL or
HLSL).
* The caller will then able to decide for itself whether it wants to compile to
native format and pass that down, or pass the language down and let it be
built internally.
* Currently BuildTargetShader still only accepts shader source.
Adam Sawicki