Commit 1365f5b311f40b93d65f27dd4c624a10d5b4be06
2022-09-09T17:19:26
Vulkan: Fix Swapchain Acquire Image Semaphore wait stage flags. There is a screen tearing on G996B with single "glClear(GL_COLOR_BUFFER_BIT)" no scissor in the frame. Fixed by defining "kSwapchainAcquireImageWaitStageFlags" and adding "VK_PIPELINE_STAGE_TRANSFER_BIT" stage flag. Also added "VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT" stage, because first use of the Swapchain Image after Acquire may be in the "glBlitFramebuffer()" command. This fix may slightly affect performance. In such case, a better fix should be implemented (include only stages based on the actual first use). However, this may be not trivial. Additionally, "kSwapchainAcquireImageWaitStageFlags" is used as a source stage mask in the "ImageLayout::Present" pipeline barrier. This is needed in order to build a dependency chain from the Acquire Image Semaphore to the layout transition's first synchronization scope, so that layout transition happens after acquire semaphore is signaled. Reference: https://github.com/KhronosGroup/Vulkan-Docs/wiki/Synchronization-Examples#combined-graphicspresent-queue https://vulkan-tutorial.com/Drawing_a_triangle/Drawing/Rendering_and_presentation Alternative fix of both issues is to define: kSwapchainAcquireImageWaitStageFlags = VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT This might potentially delay command buffer execution relative to the Swapchain Acquire Image Semaphore signal operations, but will relax the pipeline barrier. Bug: angleproject:8030 Test: angle_end2end_tests --gtest_also_run_disabled_tests --gtest_filter=EGLSurfaceTest.DISABLED_RandomClearTearing* Change-Id: I29f58862c4b369524b2555dd944e2fb67eebe956 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4271377 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Igor Nazarov <i.nazarov@samsung.com> Reviewed-by: Charlie Lao <cclao@google.com>