[gpu.vulkan] setup debug callback. the current problems are caused by…

… multiple passes in the same graph writing to the system image, which automatically transitions and blits the system image to the swapchain image. this should instead happen at the end of the graph if at least one write to the system image occurred

src/tz/gpu/rhi_vulkan.cpp

@@ -39,6 +39,7 @@ namespace tz::gpu
 	} settings;
 
 	VkInstance current_instance = VK_NULL_HANDLE;
+	VkDebugUtilsMessengerEXT debug_messenger = VK_NULL_HANDLE;
 	VkDevice current_device = VK_NULL_HANDLE;
 	VkSurfaceKHR surface = VK_NULL_HANDLE;
 	VkSwapchainKHR swapchain = VK_NULL_HANDLE;
@@ -180,6 +181,9 @@ namespace tz::gpu
 	PFN_vkCmdBeginDebugUtilsLabelEXT vkCmdBeginDebugUtilsLabelEXT;
 	PFN_vkCmdEndDebugUtilsLabelEXT vkCmdEndDebugUtilsLabelEXT;
 
+	PFN_vkCreateDebugUtilsMessengerEXT vkCreateDebugUtilsMessengerEXT;
+	PFN_vkDestroyDebugUtilsMessengerEXT vkDestroyDebugUtilsMessengerEXT;
+
 	/////////////////// chunky impl predecls ///////////////////
 	#define ERROR_UNLESS_INIT if(current_instance == VK_NULL_HANDLE) return tz::error_code::precondition_failure;
 	#define ASSERT_INIT tz_assert(current_instance != VK_NULL_HANDLE, "Topaz has not been initialised.");
@@ -193,6 +197,7 @@ namespace tz::gpu
 	// returns partial_success if the swapchain previously existed, but has been recreated for some important reason (you will maybe need to rerecord commands)
 	// returns oom if oom, voom if voom
 	// returns unknown_error if some undocumented vulkan error occurred.
+	VKAPI_PTR VkBool32 impl_debug_callback(VkDebugUtilsMessageSeverityFlagBitsEXT, VkDebugUtilsMessageTypeFlagsEXT, const VkDebugUtilsMessengerCallbackDataEXT*, void*);
 	std::pair<std::uint32_t, std::uint32_t> impl_get_image_dimensions(tz::gpu::resource_handle imagey_resource);
 	tz::error_code impl_need_swapchain(std::uint32_t w, std::uint32_t h);
 	void impl_force_new_swapchain();
@@ -267,6 +272,21 @@ namespace tz::gpu
 			vkSetDebugUtilsObjectNameEXT = reinterpret_cast<PFN_vkSetDebugUtilsObjectNameEXT>(vkGetInstanceProcAddr(current_instance, "vkSetDebugUtilsObjectNameEXT"));
 			vkCmdBeginDebugUtilsLabelEXT = reinterpret_cast<PFN_vkCmdBeginDebugUtilsLabelEXT>(vkGetInstanceProcAddr(current_instance, "vkCmdBeginDebugUtilsLabelEXT"));
 			vkCmdEndDebugUtilsLabelEXT = reinterpret_cast<PFN_vkCmdEndDebugUtilsLabelEXT>(vkGetInstanceProcAddr(current_instance, "vkCmdEndDebugUtilsLabelEXT"));
+
+			vkCreateDebugUtilsMessengerEXT = reinterpret_cast<PFN_vkCreateDebugUtilsMessengerEXT>(vkGetInstanceProcAddr(current_instance, "vkCreateDebugUtilsMessengerEXT"));
+			vkDestroyDebugUtilsMessengerEXT = reinterpret_cast<PFN_vkDestroyDebugUtilsMessengerEXT>(vkGetInstanceProcAddr(current_instance, "vkDestroyDebugUtilsMessengerEXT"));
+
+			VkDebugUtilsMessengerCreateInfoEXT debug_create
+			{
+				.sType = VK_STRUCTURE_TYPE_DEBUG_UTILS_MESSENGER_CREATE_INFO_EXT,
+				.pNext = nullptr,
+				.flags = 0,
+				.messageSeverity = VK_DEBUG_UTILS_MESSAGE_SEVERITY_ERROR_BIT_EXT | VK_DEBUG_UTILS_MESSAGE_SEVERITY_WARNING_BIT_EXT | VK_DEBUG_UTILS_MESSAGE_SEVERITY_INFO_BIT_EXT,
+				.messageType = VK_DEBUG_UTILS_MESSAGE_TYPE_VALIDATION_BIT_EXT | VK_DEBUG_UTILS_MESSAGE_TYPE_PERFORMANCE_BIT_EXT | VK_DEBUG_UTILS_MESSAGE_TYPE_GENERAL_BIT_EXT,
+				.pfnUserCallback = impl_debug_callback,
+				.pUserData = nullptr
+			};
+			vkCreateDebugUtilsMessengerEXT(current_instance, &debug_create, nullptr, &debug_messenger);
 		#endif
 	}
 
@@ -389,6 +409,13 @@ namespace tz::gpu
 			surface = VK_NULL_HANDLE;
 		}
 		tz_assert(current_instance != VK_NULL_HANDLE, "Requested to terminate tz::gpu (vulkan) when the vulkan instance was null, implying we had never initialised. This is a game-side logic error.");
+		#if TOPAZ_DEBUG
+			if(debug_messenger != VK_NULL_HANDLE)
+			{
+				vkDestroyDebugUtilsMessengerEXT(current_instance, debug_messenger, nullptr);
+				debug_messenger = VK_NULL_HANDLE;
+			}
+		#endif
 		vkDestroyInstance(current_instance, nullptr);
 		current_hardware = {};
 		current_instance = VK_NULL_HANDLE;
@@ -1821,6 +1848,21 @@ namespace tz::gpu
 
 	/////////////////// chunky impl IMPLEMENTATION ///////////////////
 
+	VKAPI_PTR VkBool32 impl_debug_callback(VkDebugUtilsMessageSeverityFlagBitsEXT severity, VkDebugUtilsMessageTypeFlagsEXT type, const VkDebugUtilsMessengerCallbackDataEXT* callback, void* usrdata)
+	{
+		(void)type;
+		(void)usrdata;
+		if(severity & VK_DEBUG_UTILS_MESSAGE_SEVERITY_ERROR_BIT_EXT)
+		{
+			tz_error("[Vulkan Error Callback]: {}\n", callback->pMessage);
+		}
+		else if(severity & VK_DEBUG_UTILS_MESSAGE_SEVERITY_WARNING_BIT_EXT)
+		{
+			tz_error("[Vulkan Warning Callback]: {}\n", callback->pMessage);
+		}		
+		return VK_FALSE;
+	}
+
 	void impl_retrieve_physical_device_info(VkPhysicalDevice from, hardware& to)
 	{
 		// get all the damn information about the stupid ass hardware, in as many lines as possible because this is vulkan