Vulkan: Smoothly recreate the swapchain using oldSwapchain on "resize" on Windows

Common/GPU/Vulkan/VulkanContext.cpp

@@ -397,6 +397,8 @@ void VulkanContext::DestroySurface() {
 	if (surface_ != VK_NULL_HANDLE) {
 		vkDestroySurfaceKHR(instance_, surface_, nullptr);
 		surface_ = VK_NULL_HANDLE;
+
+		// NOTE: We do not reset winSysData1 and 2, it's useful for debugging to compare them.
 	}
 }
 
@@ -935,6 +937,12 @@ void VulkanContext::SetDebugNameImpl(uint64_t handle, VkObjectType type, const c
 
 VkResult VulkanContext::InitSurface(WindowSystem winsys, void *data1, void *data2) {
 	winsys_ = winsys;
+	if (winsysData1_ != data1) {
+		WARN_LOG(Log::G3D, "winsysData1 changed from %p to %p", winsysData1_, data1);
+	}
+	if (winsysData2_ != data2) {
+		WARN_LOG(Log::G3D, "winsysData2 changed from %p to %p", winsysData2_, data2);
+	}
 	winsysData1_ = data1;
 	winsysData2_ = data2;
 	return ReinitSurface();
@@ -1344,6 +1352,10 @@ bool VulkanContext::InitSwapchain() {
 		return false;
 	}
 
+	if (swapchain_) {
+		INFO_LOG(Log::G3D, "Swapchain already exists, recreating...");
+	}
+
 	VkResult res = vkGetPhysicalDeviceSurfaceCapabilitiesKHR(physical_devices_[physical_device_], surface_, &surfCapabilities_);
 	if (res == VK_ERROR_SURFACE_LOST_KHR) {
 		// Not much to do.
@@ -1496,6 +1508,8 @@ bool VulkanContext::InitSwapchain() {
 		}
 	}
 
+	VkSwapchainKHR oldSwapchain = swapchain_;
+
 	VkSwapchainCreateInfoKHR swap_chain_info{ VK_STRUCTURE_TYPE_SWAPCHAIN_CREATE_INFO_KHR };
 	swap_chain_info.surface = surface_;
 	swap_chain_info.minImageCount = desiredNumberOfSwapChainImages;
@@ -1506,7 +1520,7 @@ bool VulkanContext::InitSwapchain() {
 	swap_chain_info.preTransform = preTransform;
 	swap_chain_info.imageArrayLayers = 1;
 	swap_chain_info.presentMode = swapchainPresentMode;
-	swap_chain_info.oldSwapchain = VK_NULL_HANDLE;
+	swap_chain_info.oldSwapchain = swapchain_;
 	swap_chain_info.clipped = true;
 	swap_chain_info.imageUsage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
 
@@ -1535,6 +1549,11 @@ bool VulkanContext::InitSwapchain() {
 	}
 	INFO_LOG(Log::G3D, "Created swapchain: %dx%d %s", swap_chain_info.imageExtent.width, swap_chain_info.imageExtent.height, (surfCapabilities_.supportedUsageFlags & VK_IMAGE_USAGE_TRANSFER_SRC_BIT) ? "(TRANSFER_SRC_BIT supported)" : "");
 	swapchainInited_ = true;
+
+	if (oldSwapchain != VK_NULL_HANDLE) {
+		vkDestroySwapchainKHR(device_, oldSwapchain, nullptr);
+		INFO_LOG(Log::G3D, "Destroyed old swapchain.");
+	}
 	return true;
 }
 

Common/GPU/Vulkan/VulkanContext.h

@@ -52,6 +52,7 @@ template<class R, class T> inline void ChainStruct(R &root, T *newStruct) {
 
 // Not all will be usable on all platforms, of course...
 enum WindowSystem {
+	WINDOWSYSTEM_UNINITIALIZED,
 #ifdef _WIN32
 	WINDOWSYSTEM_WIN32,
 #endif
@@ -450,7 +451,7 @@ private:
 
 	bool CheckLayers(const std::vector<LayerProperties> &layer_props, const std::vector<const char *> &layer_names) const;
 
-	WindowSystem winsys_{};
+	WindowSystem winsys_ = WINDOWSYSTEM_UNINITIALIZED;
 
 	// Don't use the real types here to avoid having to include platform-specific stuff
 	// that we really don't want in everything that uses VulkanContext.

Common/GPU/Vulkan/VulkanQueueRunner.cpp

@@ -174,7 +174,6 @@ bool VulkanQueueRunner::InitDepthStencilBuffer(VkCommandBuffer cmd, VulkanBarrie
 	return true;
 }
 
-
 void VulkanQueueRunner::DestroyBackBuffers() {
 	if (depth_.view) {
 		vulkan_->Delete().QueueDeleteImageView(depth_.view);

Windows/GPU/WindowsVulkanContext.cpp

@@ -164,7 +164,6 @@ void WindowsVulkanContext::Shutdown() {
 
 void WindowsVulkanContext::Resize() {
 	draw_->HandleEvent(Draw::Event::LOST_BACKBUFFER, vulkan_->GetBackbufferWidth(), vulkan_->GetBackbufferHeight());
-	vulkan_->DestroySwapchain();
 	VulkanContext::CreateInfo info{};
 	InitVulkanCreateInfoFromConfig(&info);
 	vulkan_->InitSwapchain();

android/jni/AndroidVulkanContext.cpp

@@ -120,13 +120,16 @@ void AndroidVulkanContext::Shutdown() {
 
 void AndroidVulkanContext::Resize() {
 	INFO_LOG(Log::G3D, "AndroidVulkanContext::Resize begin (oldsize: %dx%d)", g_Vulkan->GetBackbufferWidth(), g_Vulkan->GetBackbufferHeight());
+	VulkanContext::CreateInfo info{};
+	InitVulkanCreateInfoFromConfig(&info);
 
 	draw_->HandleEvent(Draw::Event::LOST_BACKBUFFER, g_Vulkan->GetBackbufferWidth(), g_Vulkan->GetBackbufferHeight());
 	g_Vulkan->DestroySwapchain();
+
+	// TODO: We should only destroy the surface here if the window changed. We can track this inside g_Vulkan.
+
 	g_Vulkan->DestroySurface();
 
-	VulkanContext::CreateInfo info{};
-	InitVulkanCreateInfoFromConfig(&info);
 	g_Vulkan->UpdateCreateInfo(info);
 
 	g_Vulkan->ReinitSurface();