Backends: Vulkan: Fixed vkAcquireNextImageKHR() validation errors in VulkanSDK 1.3.275 by allocating one extra semaphore than in-flight frames. (#7236)

backends/imgui_impl_vulkan.cpp

@@ -35,6 +35,7 @@
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
 //  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-01-19: Vulkan: Fixed vkAcquireNextImageKHR() validation errors in VulkanSDK 1.3.275 by allocating one extra semaphore than in-flight frames. (#7236)
 //  2024-01-11: Vulkan: Fixed vkMapMemory() calls unnecessarily using full buffer size (#3957). Fixed MinAllocationSize handing (#7189).
 //  2024-01-03: Vulkan: Added MinAllocationSize field in ImGui_ImplVulkan_InitInfo to workaround zealous "best practice" validation layer. (#7189, #4238)
 //  2024-01-03: Vulkan: Stoped creating command pools with VK_COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT as we don't reset them.
@@ -1354,15 +1355,13 @@ VkPresentModeKHR ImGui_ImplVulkanH_SelectPresentMode(VkPhysicalDevice physical_d
 void ImGui_ImplVulkanH_CreateWindowCommandBuffers(VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wd, uint32_t queue_family, const VkAllocationCallbacks* allocator)
 {
     IM_ASSERT(physical_device != VK_NULL_HANDLE && device != VK_NULL_HANDLE);
-    (void)physical_device;
-    (void)allocator;
+    IM_UNUSED(physical_device);
 
     // Create Command Buffers
     VkResult err;
     for (uint32_t i = 0; i < wd->ImageCount; i++)
     {
         ImGui_ImplVulkanH_Frame* fd = &wd->Frames[i];
-        ImGui_ImplVulkanH_FrameSemaphores* fsd = &wd->FrameSemaphores[i];
         {
             VkCommandPoolCreateInfo info = {};
             info.sType = VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO;
@@ -1387,6 +1386,11 @@ void ImGui_ImplVulkanH_CreateWindowCommandBuffers(VkPhysicalDevice physical_devi
             err = vkCreateFence(device, &info, allocator, &fd->Fence);
             check_vk_result(err);
         }
+    }
+
+    for (uint32_t i = 0; i < wd->SemaphoreCount; i++)
+    {
+        ImGui_ImplVulkanH_FrameSemaphores* fsd = &wd->FrameSemaphores[i];
         {
             VkSemaphoreCreateInfo info = {};
             info.sType = VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO;
@@ -1422,10 +1426,9 @@ void ImGui_ImplVulkanH_CreateWindowSwapChain(VkPhysicalDevice physical_device, V
     // We don't use ImGui_ImplVulkanH_DestroyWindow() because we want to preserve the old swapchain to create the new one.
     // Destroy old Framebuffer
     for (uint32_t i = 0; i < wd->ImageCount; i++)
-    {
         ImGui_ImplVulkanH_DestroyFrame(device, &wd->Frames[i], allocator);
+    for (uint32_t i = 0; i < wd->SemaphoreCount; i++)
         ImGui_ImplVulkanH_DestroyFrameSemaphores(device, &wd->FrameSemaphores[i], allocator);
-    }
     IM_FREE(wd->Frames);
     IM_FREE(wd->FrameSemaphores);
     wd->Frames = nullptr;
@@ -1484,11 +1487,12 @@ void ImGui_ImplVulkanH_CreateWindowSwapChain(VkPhysicalDevice physical_device, V
         err = vkGetSwapchainImagesKHR(device, wd->Swapchain, &wd->ImageCount, backbuffers);
         check_vk_result(err);
 
-        IM_ASSERT(wd->Frames == nullptr);
+        IM_ASSERT(wd->Frames == nullptr && wd->FrameSemaphores == nullptr);
+        wd->SemaphoreCount = wd->ImageCount + 1;
         wd->Frames = (ImGui_ImplVulkanH_Frame*)IM_ALLOC(sizeof(ImGui_ImplVulkanH_Frame) * wd->ImageCount);
-        wd->FrameSemaphores = (ImGui_ImplVulkanH_FrameSemaphores*)IM_ALLOC(sizeof(ImGui_ImplVulkanH_FrameSemaphores) * wd->ImageCount);
+        wd->FrameSemaphores = (ImGui_ImplVulkanH_FrameSemaphores*)IM_ALLOC(sizeof(ImGui_ImplVulkanH_FrameSemaphores) * wd->SemaphoreCount);
         memset(wd->Frames, 0, sizeof(wd->Frames[0]) * wd->ImageCount);
-        memset(wd->FrameSemaphores, 0, sizeof(wd->FrameSemaphores[0]) * wd->ImageCount);
+        memset(wd->FrameSemaphores, 0, sizeof(wd->FrameSemaphores[0]) * wd->SemaphoreCount);
         for (uint32_t i = 0; i < wd->ImageCount; i++)
             wd->Frames[i].Backbuffer = backbuffers[i];
     }
@@ -1596,10 +1600,9 @@ void ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui
     //vkQueueWaitIdle(bd->Queue);
 
     for (uint32_t i = 0; i < wd->ImageCount; i++)
-    {
         ImGui_ImplVulkanH_DestroyFrame(device, &wd->Frames[i], allocator);
+    for (uint32_t i = 0; i < wd->SemaphoreCount; i++)
         ImGui_ImplVulkanH_DestroyFrameSemaphores(device, &wd->FrameSemaphores[i], allocator);
-    }
     IM_FREE(wd->Frames);
     IM_FREE(wd->FrameSemaphores);
     wd->Frames = nullptr;
@@ -1873,8 +1876,8 @@ static void ImGui_ImplVulkan_SwapBuffers(ImGuiViewport* viewport, void*)
     else
         check_vk_result(err);
 
-    wd->FrameIndex = (wd->FrameIndex + 1) % wd->ImageCount;         // This is for the next vkWaitForFences()
-    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->ImageCount; // Now we can use the next set of semaphores
+    wd->FrameIndex = (wd->FrameIndex + 1) % wd->ImageCount;             // This is for the next vkWaitForFences()
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
 }
 
 void ImGui_ImplVulkan_InitPlatformInterface()

backends/imgui_impl_vulkan.h

@@ -156,6 +156,7 @@ struct ImGui_ImplVulkanH_Window
     VkClearValue        ClearValue;
     uint32_t            FrameIndex;             // Current frame being rendered to (0 <= FrameIndex < FrameInFlightCount)
     uint32_t            ImageCount;             // Number of simultaneous in-flight frames (returned by vkGetSwapchainImagesKHR, usually derived from min_image_count)
+    uint32_t            SemaphoreCount;         // Number of simultaneous in-flight frames + 1, to be able to use it in vkAcquireNextImageKHR
     uint32_t            SemaphoreIndex;         // Current set of swapchain wait semaphores we're using (needs to be distinct from per frame data)
     ImGui_ImplVulkanH_Frame*            Frames;
     ImGui_ImplVulkanH_FrameSemaphores*  FrameSemaphores;

docs/CHANGELOG.txt

@@ -53,6 +53,8 @@ Other changes:
   regression from 1.90.1 related to code scoping Tab presses to local scope. (#7226) [@bratpilz]
 - Debug Tools: Metrics: Fixed debug break in SetShortcutRouting() not handling ImGuiMod_Shortcut redirect.
 - Debug Tools: Debug Log: Added "Input Routing" logging.
+- Backends: Vulkan: Fixed vkAcquireNextImageKHR() validation errors in VulkanSDK 1.3.275 by
+  allocating one extra semaphore than in-flight frames. (#7236) [@mklefrancois]
 - Backends: Vulkan: Fixed vkMapMemory() calls unnecessarily using full buffer size. (#3957)
 - Backends: Vulkan: Fixed handling of ImGui_ImplVulkan_InitInfo::MinAllocationSize field. (#7189, #4238)
 - Backends: WebGPU: Filling all WGPUDepthStencilState fields explicitly as a recent Dawn

examples/example_glfw_vulkan/main.cpp

@@ -376,7 +376,7 @@ static void FramePresent(ImGui_ImplVulkanH_Window* wd)
         return;
     }
     check_vk_result(err);
-    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->ImageCount; // Now we can use the next set of semaphores
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
 }
 
 // Main code

examples/example_sdl2_vulkan/main.cpp

@@ -364,7 +364,7 @@ static void FramePresent(ImGui_ImplVulkanH_Window* wd)
         return;
     }
     check_vk_result(err);
-    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->ImageCount; // Now we can use the next set of semaphores
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
 }
 
 // Main code