Metal: Fix raster order group AMD workaround
The AMD-specific raster order group workaround relied
on disabled framebuffer attachments being implemented
via all-disabled color masks.
Metal backend no longer includes disabled framebuffer
attachments in render pass descriptors.
Updated the workaround to keep the
placeholder attachment enabled and
to set its color mask explicitly.
Fixed: angleproject:8263
Change-Id: I815ceede84e6ea89eefc10c445768d9d569d0d82
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5208110
Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
diff --git a/src/libANGLE/PixelLocalStorage.cpp b/src/libANGLE/PixelLocalStorage.cpp
index 5c89a00..9b5d07e 100644
--- a/src/libANGLE/PixelLocalStorage.cpp
+++ b/src/libANGLE/PixelLocalStorage.cpp
@@ -639,20 +639,36 @@
// textures on AMD when the render pass doesn't have a color attachment on slot 0. To
// work around this we attach one of the PLS textures to GL_COLOR_ATTACHMENT0, if there
// isn't one already.
+ // It's important to keep the attachment enabled so that it's set in the corresponding
+ // MTLRenderPassAttachmentDescriptor. As the fragment shader does not have any output
+ // bound to this attachment, set the color write mask to all-disabled.
+ // Note that the PLS extension disallows simultaneously binding a single texture image
+ // to a PLS plane and attaching it to the draw framebuffer. Enabling this workaround on
+ // any other platform would yield incorrect results.
mHadColorAttachment0 = framebuffer->getColorAttachment(0) != nullptr;
if (!mHadColorAttachment0)
{
+ // Indexed color masks are always available on Metal.
+ ASSERT(context->getExtensions().drawBuffersIndexedAny());
+ // Remember the current draw buffer 0 color mask and set it to all-disabled.
+ state.getBlendStateExt().getColorMaskIndexed(
+ 0, &mSavedColorMask[0], &mSavedColorMask[1], &mSavedColorMask[2],
+ &mSavedColorMask[3]);
+ ContextPrivateColorMaski(context->getMutablePrivateState(),
+ context->getMutablePrivateStateCache(), 0, false, false,
+ false, false);
+
// Remember the current draw buffer state so we can restore it during onEnd().
const DrawBuffersVector<GLenum> &appDrawBuffers =
framebuffer->getDrawBufferStates();
mSavedDrawBuffers.resize(appDrawBuffers.size());
std::copy(appDrawBuffers.begin(), appDrawBuffers.end(), mSavedDrawBuffers.begin());
- // Turn off draw buffer 0.
- if (mSavedDrawBuffers[0] != GL_NONE)
+ // Turn on draw buffer 0.
+ if (mSavedDrawBuffers[0] != GL_COLOR_ATTACHMENT0)
{
GLenum drawBuffer0 = mSavedDrawBuffers[0];
- mSavedDrawBuffers[0] = GL_NONE;
+ mSavedDrawBuffers[0] = GL_COLOR_ATTACHMENT0;
context->drawBuffers(static_cast<GLsizei>(mSavedDrawBuffers.size()),
mSavedDrawBuffers.data());
mSavedDrawBuffers[0] = drawBuffer0;
@@ -773,12 +789,17 @@
TextureTarget::_2D, TextureID(), 0);
// Restore the draw buffer state from before PLS was enabled.
- if (mSavedDrawBuffers[0] != GL_NONE)
+ if (mSavedDrawBuffers[0] != GL_COLOR_ATTACHMENT0)
{
context->drawBuffers(static_cast<GLsizei>(mSavedDrawBuffers.size()),
mSavedDrawBuffers.data());
}
mSavedDrawBuffers.clear();
+
+ // Restore the draw buffer 0 color mask.
+ ContextPrivateColorMaski(
+ context->getMutablePrivateState(), context->getMutablePrivateStateCache(), 0,
+ mSavedColorMask[0], mSavedColorMask[1], mSavedColorMask[2], mSavedColorMask[3]);
}
}
else
@@ -808,6 +829,7 @@
std::vector<ImageUnit> mSavedImageBindings;
// If mPLSOptions.plsRenderPassNeedsColorAttachmentWorkaround.
bool mHadColorAttachment0;
+ std::array<bool, 4> mSavedColorMask;
DrawBuffersVector<GLenum> mSavedDrawBuffers;
// If !mPLSOptions.plsRenderPassNeedsColorAttachmentWorkaround.
GLint mSavedFramebufferDefaultWidth;
