fix: use one render-finished semaphore per swapchain image - #183
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fix: use one render-finished semaphore per swapchain image#183TommyRadan wants to merge 1 commit into
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The Vulkan backend signaled and present-waited on a single device-wide m_render_finished semaphore every frame. The in-flight fence only gates the submit, not the present, so with 3 swapchain images frame N+1's submit could re-signal the semaphore while frame N's present was still using it, tripping VUID-vkQueueSubmit-pSignalSemaphores-00067. Use one render-finished semaphore per swapchain image, indexed by the acquired image index, and tie its lifetime to the swapchain so it tracks image-count changes on resize. A semaphore bound to a specific image is not re-signaled until that image is re-acquired, which the acquire/fence flow already gates, so the reuse hazard is gone. Closes #151
CI build artifactsWindows Debug and Release builds are attached to the workflow run summary under Artifacts:
Run #249 — commit |
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Summary
Fixes the Vulkan validation error from #151:
VUID-vkQueueSubmit-pSignalSemaphores-00067— the swapchain render-finished semaphore was reused across frames.The backend signaled and present-waited on a single device-wide
m_render_finishedsemaphore. The in-flight fence only gates the submit, not the present, so with 3 swapchain images frame N+1's submit could re-signal the semaphore while frame N's present was still using it.Changes
vk_device.hpp:m_render_finishedis now astd::vector<VkSemaphore>(one per swapchain image) instead of a single handle.create_swapchain/destroy_swapchain: create and destroy the per-image semaphores alongside the swapchain, so the count tracks image-count changes on resize.create_sync_objects/destroy_sync_objects: now own onlym_image_availableandm_in_flight_fence.submit: signals and present-waits onm_render_finished[m_current_image_index].A semaphore tied to a specific image is not re-signaled until that image is re-acquired — already gated by the acquire/fence flow — so the reuse hazard is gone.
m_image_availableandm_in_flight_fenceare unchanged (single-frame-in-flight model).Testing
AlphaEnginetarget (Ninja, Debug) — links cleanly.clang-format-18clean on both changed files.Note: the validation message itself wasn't re-run — this was built in a headless container with no GPU/display, so the fix is verified by build + code reasoning rather than a live capture.
Closes #151
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