kc3-lang/angle

2024-09-23T16:09:12

Vulkan: Fix the error from multiple lineloop draws Since Vulkan does not support line-loop draws natively, such a draw call requires the conversion of the related buffers to prepare them for this operation. For glDrawElementsIndirect(), the index and the indirect buffers would need conversion. However, what currently happens in this case is that the original buffer pointer is overwritten after the conversion, removing the link to the original buffer. Therefore, if there is a second line-loop call just after the first, it will try to use the converted buffer as the new source, which leads to errors due the buffer already being in use. The index buffer for the draw is bound when the related dirty bit is handled. Therefore, instead of using the draw index buffer directly for handling the line-loop scenario, we can use the index buffer in the form of a local pointer passed between functions. Then, in order to reconcile line-loop with the other cases, the draw index buffer is set just before setting up the indexed draw. * Functions handling line-loop draws do not modify the element array buffer in VertexArrayVk directly, but use local buffer pointers to pass the current element array pointer to further processing and drawing. * Added mCurrentElementArrayBuffer for ContextVk to be bound to the index buffer to used for draw instead of the one from its vertex array object. * Before the indexed draw, mCurrentElementArrayBuffer is set to the last destination index buffer. * Added unit test that makes a line-loop draw and then a non-LL call using the same element array. Bug: angleproject:360758685 Change-Id: I6d6328f6326c1a1f9f80e5ef346aa077c867d344 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5878764 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Amirali Abdolrashidi <abdolrashidi@google.com> Reviewed-by: Charlie Lao <cclao@google.com>