commit dc2c5c5a419e45891ec5898e675b8f447b1bd9fa
author Ian Elliott <ianelliott@google.com> Fri Aug 02 09:32:18 2019 -0600
committer Commit Bot <commit-bot@chromium.org> Sat Aug 03 05:51:01 2019 +0000
tree 4aae47df7e9ee26098b81df1e68a32f701bf12dc
parent 8a43b8c7a9c52a700455d79d6d282bc8e48cf680

Vulkan: Initial Implementation of PBO support (software only)

This contains support for both pixel unpack buffers (i.e. for glTex*Image*)
and pixel pack buffers (i.e. for glReadPixels).

Bug: angleproject:3209
Bug: angleproject:3210
Change-Id: I077cccbffb96fb5f0198922bc7c1850a7eb3f616
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1723096
Commit-Queue: Ian Elliott <ianelliott@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>

src/libANGLE/renderer/vulkan/FramebufferVk.cpp

diff --git a/src/libANGLE/renderer/vulkan/FramebufferVk.cpp b/src/libANGLE/renderer/vulkan/FramebufferVk.cpp
index 5a00888..eee1d58 100644
--- a/src/libANGLE/renderer/vulkan/FramebufferVk.cpp
+++ b/src/libANGLE/renderer/vulkan/FramebufferVk.cpp
@@ -1515,8 +1515,24 @@
     // created with the host coherent bit.
     ANGLE_TRY(mReadPixelBuffer.invalidate(contextVk));
 
-    PackPixels(packPixelsParams, *readFormat, area.width * readFormat->pixelBytes, readPixelBuffer,
-               static_cast<uint8_t *>(pixels));
+    const gl::State &glState = contextVk->getState();
+    gl::Buffer *packBuffer   = glState.getTargetBuffer(gl::BufferBinding::PixelPack);
+    if (packBuffer != nullptr)
+    {
+        // Must map the PBO in order to read its contents (and then unmap it later)
+        BufferVk *packBufferVk = vk::GetImpl(packBuffer);
+        void *mapPtr           = nullptr;
+        ANGLE_TRY(packBufferVk->mapImpl(contextVk, &mapPtr));
+        uint8_t *dest = static_cast<uint8_t *>(mapPtr) + reinterpret_cast<ptrdiff_t>(pixels);
+        PackPixels(packPixelsParams, *readFormat, area.width * readFormat->pixelBytes,
+                   readPixelBuffer, static_cast<uint8_t *>(dest));
+        packBufferVk->unmapImpl(contextVk);
+    }
+    else
+    {
+        PackPixels(packPixelsParams, *readFormat, area.width * readFormat->pixelBytes,
+                   readPixelBuffer, static_cast<uint8_t *>(pixels));
+    }
 
     return angle::Result::Continue;
 }