mirror of
https://github.com/MobileGL-Dev/MobileGL
synced 2026-09-09 20:58:31 +09:00
swung0x48
0f99d93300
Wire GL_SRC1_* dual-source blend factors (glBlendFunc) end to end with the
glBindFragDataLocationIndexed color index, so a fragment shader can drive both
dual-source blend inputs.
State + converters:
- RenderState BlendFactor gains Src1Color/OneMinusSrc1Color/Src1Alpha/
OneMinusSrc1Alpha; GLToMG/MGToGL/MGToVk/MGToStr converters map them to
GL_SRC1_*, VK_BLEND_FACTOR_SRC1_*, and readable names.
Transpiler layout(index = N):
- ProgramAttrib carries explicitFragmentOutIndices; ProgramObject threads
m_explicitFragDataIndex into it at both link sites.
- TMglGlslIoResolver applies the color index as TQualifier.layoutIndex on the
fragment output, emitting layout(index = 1) via the glslang Index decoration
-> SPIRV-Cross path. Only the non-zero (dual-source) index is emitted: index 0
is the GL default and an explicit "index = 0" would demand
GL_EXT_blend_func_extended on GLES for ordinary single-source outputs.
Feature detection, POST, and hard-fail at use time (no silent fallback):
- Vulkan: dualSrcBlend is detected at device creation and cached; a draw whose
enabled blend state uses a SRC1 factor without the feature throws at pipeline
build with the reason and a pointer to the POST row.
- GLES: GL_EXT_blend_func_extended detected at load into
GLESCapabilities.SupportsDualSourceBlend; a draw enabling blend with a SRC1
factor without it throws in the blend-state sync with the same guidance.
- DriverPost adds a dual-source-blend row for both backends (Pass/Warn).
Tests:
- ProgramTest.CompileAndLinkWithExplicitFragmentOut now asserts the transpiled
fragment shader carries layout(location = 0, index = 1) after a re-link with
glBindFragDataLocationIndexed(index 1), and still omits any index qualifier
for the plain index-0 output.