implement SetData and GetData

src/Refresh_Driver_Vulkan.c

@@ -695,11 +695,32 @@ static const VulkanResourceAccessInfo AccessMap[RESOURCE_ACCESS_TYPES_COUNT] =
 
 /* Memory structures */
 
-typedef struct VulkanBufferContainer /* cast from Refresh_Buffer */
+/* We use pointer indirection so that defrag can occur without objects
+ * needing to be aware of the backing buffers changing.
+ */
+typedef struct VulkanBufferContainer
 {
 	VulkanBuffer *vulkanBuffer;
 } VulkanBufferContainer;
 
+/* CpuBuffers consist of multiple backing buffer containers so that data transfers
+ * can occur safely without the client having to explicitly manage transfer timing.
+ */
+typedef struct VulkanCpuBufferContainer /* cast from Refresh_CpuBuffer */
+{
+	uint32_t sizeInBytes;
+	VulkanBufferContainer *activeBuffer;
+
+	/* These are all the buffers that have been used by this container.
+	 * If a buffer is bound and then updated with Discard, a new buffer
+	 * will be added to this list.
+	 * These can be reused after they are submitted and command processing is complete.
+	 */
+	uint32_t bufferCapacity;
+	uint32_t bufferCount;
+	VulkanBufferContainer **backingBuffers;
+} VulkanCpuBufferContainer;
+
 struct VulkanBuffer
 {
 	VkBuffer buffer;
@@ -711,10 +732,13 @@ struct VulkanBuffer
 	uint8_t requireHostVisible;
 	uint8_t preferDeviceLocal;
 	uint8_t requireHostLocal;
+	uint8_t preserveContentsOnDefrag;
 
 	SDL_atomic_t referenceCount; /* Tracks command buffer usage */
 
 	VulkanBufferContainer *container;
+
+	uint8_t markedForDestroy; /* so that defrag doesn't double-free */
 };
 
 typedef enum VulkanUniformBufferType
@@ -802,6 +826,8 @@ struct VulkanTexture
 	SDL_atomic_t referenceCount;
 
 	VulkanTextureContainer *container;
+
+	uint8_t markedForDestroy; /* so that defrag doesn't double-free */
 };
 
 typedef struct VulkanRenderTarget
@@ -3248,6 +3274,28 @@ static void VULKAN_INTERNAL_ImageMemoryBarrier(
 
 /* Resource tracking */
 
+#define ADD_TO_ARRAY_UNIQUE(resource, type, array, count, capacity) \
+	uint32_t i; \
+	\
+	for (i = 0; i < commandBuffer->count; i += 1) \
+	{ \
+		if (commandBuffer->array[i] == resource) \
+		{ \
+			return; \
+		} \
+	} \
+	\
+	if (commandBuffer->count == commandBuffer->capacity) \
+	{ \
+		commandBuffer->capacity += 1; \
+		commandBuffer->array = SDL_realloc( \
+			commandBuffer->array, \
+			commandBuffer->capacity * sizeof(type) \
+		); \
+	} \
+	commandBuffer->array[commandBuffer->count] = resource; \
+	commandBuffer->count += 1;
+
 #define TRACK_RESOURCE(resource, type, array, count, capacity) \
 	uint32_t i; \
 	\
@@ -3269,10 +3317,8 @@ static void VULKAN_INTERNAL_ImageMemoryBarrier(
 	} \
 	commandBuffer->array[commandBuffer->count] = resource; \
 	commandBuffer->count += 1; \
-	\
 	SDL_AtomicIncRef(&resource->referenceCount);
 
-
 static void VULKAN_INTERNAL_TrackBuffer(
 	VulkanRenderer *renderer,
 	VulkanCommandBuffer *commandBuffer,
@@ -3391,7 +3437,7 @@ static void VULKAN_INTERNAL_TrackCopiedTexture(
 	VulkanCommandBuffer *commandBuffer,
 	VulkanTexture *texture
 ) {
-	TRACK_RESOURCE(
+	ADD_TO_ARRAY_UNIQUE(
 		texture,
 		VulkanTexture*,
 		copiedTextures,
@@ -3406,7 +3452,7 @@ static void VULKAN_INTERNAL_TrackCopiedBuffer(
 	VulkanCommandBuffer *commandBuffer,
 	VulkanBuffer *buffer
 ) {
-	TRACK_RESOURCE(
+	ADD_TO_ARRAY_UNIQUE(
 		buffer,
 		VulkanBuffer*,
 		copiedGpuBuffers,
@@ -4145,7 +4191,8 @@ static VulkanBuffer* VULKAN_INTERNAL_CreateBuffer(
 	uint8_t requireHostVisible,
 	uint8_t requireHostLocal,
 	uint8_t preferDeviceLocal,
-	uint8_t dedicatedAllocation
+	uint8_t dedicatedAllocation,
+	uint8_t preserveContentsOnDefrag
 ) {
 	VulkanBuffer* buffer;
 	VkResult vulkanResult;
@@ -4160,6 +4207,8 @@ static VulkanBuffer* VULKAN_INTERNAL_CreateBuffer(
 	buffer->requireHostVisible = requireHostVisible;
 	buffer->requireHostLocal = requireHostLocal;
 	buffer->preferDeviceLocal = preferDeviceLocal;
+	buffer->preserveContentsOnDefrag = preserveContentsOnDefrag;
+	buffer->markedForDestroy = 0;
 
 	bufferCreateInfo.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
 	bufferCreateInfo.pNext = NULL;
@@ -4277,6 +4326,7 @@ static VulkanUniformBufferObject* VULKAN_INTERNAL_CreateUniformBufferObject(
 		1,
 		0,
 		1,
+		1,
 		1
 	);
 
@@ -4321,12 +4371,17 @@ static VulkanUniformBufferObject* VULKAN_INTERNAL_CreateUniformBufferObject(
 	return uniformBufferObject;
 }
 
-/* Buffer indirection so we can cleanly defrag GpuBuffers */
+/* Indirection so we can cleanly defrag buffers */
 static VulkanBufferContainer* VULKAN_INTERNAL_CreateBufferContainer(
 	VulkanRenderer *renderer,
 	uint32_t sizeInBytes,
 	VulkanResourceAccessType resourceAccessType,
-	VkBufferUsageFlags usageFlags
+	VkBufferUsageFlags usageFlags,
+	uint8_t requireHostVisible,
+	uint8_t requireHostLocal,
+	uint8_t preferDeviceLocal,
+	uint8_t dedicatedAllocation,
+	uint8_t preserveContentsOnDefrag
 ) {
 	VulkanBufferContainer* bufferContainer;
 	VulkanBuffer* buffer;
@@ -4339,10 +4394,11 @@ static VulkanBufferContainer* VULKAN_INTERNAL_CreateBufferContainer(
 		sizeInBytes,
 		resourceAccessType,
 		usageFlags,
-		0,
+		requireHostVisible,
-		0,
+		requireHostLocal,
-		1,
+		preferDeviceLocal,
-		0
+		dedicatedAllocation,
+		preserveContentsOnDefrag
 	);
 
 	if (buffer == NULL)
@@ -5413,6 +5469,7 @@ static VulkanTexture* VULKAN_INTERNAL_CreateTexture(
 
 	texture->isCube = 0;
 	texture->is3D = 0;
+	texture->markedForDestroy = 0;
 
 	if (isCube)
 	{
@@ -6812,20 +6869,26 @@ static Refresh_GpuBuffer* VULKAN_CreateGpuBuffer(
 		(VulkanRenderer*) driverData,
 		sizeInBytes,
 		resourceAccessType,
-		vulkanUsageFlags
+		vulkanUsageFlags,
+		0,
+		0,
+		1,
+		0,
+		1
 	);
 }
 
 static Refresh_CpuBuffer* VULKAN_CreateCpuBuffer(
 	Refresh_Renderer *driverData,
-	uint32_t sizeInBytes,
+	uint32_t sizeInBytes
-	void **pDataPtr
 ) {
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
 	VkBufferUsageFlags vulkanUsageFlags =
 		VK_BUFFER_USAGE_TRANSFER_SRC_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
+	VulkanCpuBufferContainer *bufferContainer = (VulkanCpuBufferContainer*) SDL_malloc(sizeof(VulkanCpuBufferContainer));
 
-	VulkanBuffer *vulkanBuffer = VULKAN_INTERNAL_CreateBuffer(
+	bufferContainer->sizeInBytes = sizeInBytes;
+	bufferContainer->activeBuffer = VULKAN_INTERNAL_CreateBufferContainer(
 		renderer,
 		sizeInBytes,
 		RESOURCE_ACCESS_NONE,
@@ -6833,12 +6896,18 @@ static Refresh_CpuBuffer* VULKAN_CreateCpuBuffer(
 		1,
 		1,
 		0,
-		1
+		0,
+		0
 	);
 
-	*pDataPtr = vulkanBuffer->usedRegion->allocation->mapPointer;
+	bufferContainer->bufferCapacity = 1;
+	bufferContainer->bufferCount = 1;
+	bufferContainer->backingBuffers = SDL_malloc(
+		bufferContainer->bufferCapacity * sizeof(VulkanBufferContainer*)
+	);
+	bufferContainer->backingBuffers[0] = bufferContainer->activeBuffer;
 
-	return (Refresh_CpuBuffer*) vulkanBuffer;
+	return (Refresh_CpuBuffer*) bufferContainer;
 }
 
 /* Setters */
@@ -7169,6 +7238,8 @@ static void VULKAN_INTERNAL_QueueDestroyTexture(
 	VulkanRenderer *renderer,
 	VulkanTexture *vulkanTexture
 ) {
+	if (vulkanTexture->markedForDestroy) { return; }
+
 	SDL_LockMutex(renderer->disposeLock);
 
 	EXPAND_ARRAY_IF_NEEDED(
@@ -7184,6 +7255,8 @@ static void VULKAN_INTERNAL_QueueDestroyTexture(
 	] = vulkanTexture;
 	renderer->texturesToDestroyCount += 1;
 
+	vulkanTexture->markedForDestroy = 1;
+
 	SDL_UnlockMutex(renderer->disposeLock);
 }
 
@@ -7232,6 +7305,8 @@ static void VULKAN_INTERNAL_QueueDestroyBuffer(
 	VulkanRenderer *renderer,
 	VulkanBuffer *vulkanBuffer
 ) {
+	if (vulkanBuffer->markedForDestroy) { return; }
+
 	SDL_LockMutex(renderer->disposeLock);
 
 	EXPAND_ARRAY_IF_NEEDED(
@@ -7247,6 +7322,8 @@ static void VULKAN_INTERNAL_QueueDestroyBuffer(
 	] = vulkanBuffer;
 	renderer->buffersToDestroyCount += 1;
 
+	vulkanBuffer->markedForDestroy = 1;
+
 	SDL_UnlockMutex(renderer->disposeLock);
 }
 
@@ -7262,7 +7339,7 @@ static void VULKAN_QueueDestroyGpuBuffer(
 
 	VULKAN_INTERNAL_QueueDestroyBuffer(renderer, vulkanBuffer);
 
-	/* Containers are just client handles, so we can destroy immediately */
+	/* Containers are just client handles, so we can free immediately */
 	SDL_free(vulkanBufferContainer);
 
 	SDL_UnlockMutex(renderer->disposeLock);
@@ -7273,11 +7350,20 @@ static void VULKAN_QueueDestroyCpuBuffer(
 	Refresh_CpuBuffer *buffer
 ) {
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
-	VulkanBuffer *vulkanBuffer = (VulkanBuffer*) buffer;
+	VulkanCpuBufferContainer *bufferContainer = (VulkanCpuBufferContainer*) buffer;
+	uint32_t i;
 
 	SDL_LockMutex(renderer->disposeLock);
 
-	VULKAN_INTERNAL_QueueDestroyBuffer(renderer, vulkanBuffer);
+	for (i = 0; i < bufferContainer->bufferCount; i += 1)
+	{
+		VULKAN_INTERNAL_QueueDestroyBuffer(renderer, bufferContainer->backingBuffers[i]->vulkanBuffer);
+		SDL_free(bufferContainer->backingBuffers[i]);
+	}
+
+	/* Containers are just client handles, so we can free immediately */
+	SDL_free(bufferContainer->backingBuffers);
+	SDL_free(bufferContainer);
 
 	SDL_UnlockMutex(renderer->disposeLock);
 }
@@ -8342,6 +8428,108 @@ static void VULKAN_EndComputePass(
 	vulkanCommandBuffer->currentComputePipeline = NULL;
 }
 
+static void VULKAN_INTERNAL_DiscardActiveCpuBuffer(
+	VulkanRenderer *renderer,
+	VulkanCpuBufferContainer *cpuBufferContainer
+) {
+	VulkanBufferContainer *cpuBuffer;
+	uint32_t i;
+
+	cpuBufferContainer->activeBuffer->vulkanBuffer->preserveContentsOnDefrag = 0;
+
+	/* If a previously-discarded buffer is available, we can use that. */
+	for (i = 0; i < cpuBufferContainer->bufferCount; i += 1)
+	{
+		cpuBuffer = cpuBufferContainer->backingBuffers[i];
+		if (SDL_AtomicGet(&cpuBuffer->vulkanBuffer->referenceCount) == 0)
+		{
+			cpuBufferContainer->activeBuffer = cpuBuffer;
+			return;
+		}
+	}
+
+	/* No buffer is available, generate a new one. */
+	cpuBufferContainer->activeBuffer = VULKAN_INTERNAL_CreateBufferContainer(
+		renderer,
+		cpuBufferContainer->sizeInBytes,
+		RESOURCE_ACCESS_NONE,
+		VK_BUFFER_USAGE_TRANSFER_SRC_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT,
+		1,
+		1,
+		0,
+		0,
+		0
+	);
+
+	EXPAND_ARRAY_IF_NEEDED(
+		cpuBufferContainer->backingBuffers,
+		VulkanBufferContainer*,
+		cpuBufferContainer->bufferCount + 1,
+		cpuBufferContainer->bufferCapacity,
+		cpuBufferContainer->bufferCapacity * 2
+	);
+
+	cpuBufferContainer->backingBuffers[
+		cpuBufferContainer->bufferCount
+	] = cpuBufferContainer->activeBuffer;
+	cpuBufferContainer->bufferCount += 1;
+}
+
+static void VULKAN_SetData(
+	Refresh_Renderer *driverData,
+	void* data,
+	Refresh_CpuBuffer *cpuBuffer,
+	Refresh_BufferCopy *copyParams,
+	Refresh_SetDataOptions option
+) {
+	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
+	VulkanCpuBufferContainer *cpuBufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
+	VulkanBuffer *vulkanBuffer = cpuBufferContainer->activeBuffer->vulkanBuffer;
+
+	if (option == REFRESH_SETDATAOPTIONS_DISCARD && SDL_AtomicGet(&vulkanBuffer->referenceCount) > 0)
+	{
+		VULKAN_INTERNAL_DiscardActiveCpuBuffer(
+			renderer,
+			cpuBufferContainer
+		);
+	}
+
+	uint8_t *bufferPointer =
+		vulkanBuffer->usedRegion->allocation->mapPointer +
+		vulkanBuffer->usedRegion->resourceOffset +
+		copyParams->dstOffset;
+
+	SDL_memcpy(
+		bufferPointer,
+		((uint8_t*) data) + copyParams->srcOffset,
+		copyParams->size
+	);
+}
+
+static void VULKAN_GetData(
+	Refresh_Renderer *driverData,
+	Refresh_CpuBuffer *cpuBuffer,
+	void* data,
+	Refresh_BufferCopy *copyParams
+) {
+	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
+	VulkanCpuBufferContainer *cpuBufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
+	VulkanBuffer *vulkanBuffer = cpuBufferContainer->activeBuffer->vulkanBuffer;
+
+	uint8_t *bufferPointer =
+		vulkanBuffer->usedRegion->allocation->mapPointer +
+		vulkanBuffer->usedRegion->resourceOffset +
+		copyParams->srcOffset;
+
+	SDL_memcpy(
+		((uint8_t*) data) + copyParams->dstOffset,
+		bufferPointer,
+		copyParams->size
+	);
+
+	vulkanBuffer->preserveContentsOnDefrag = 0;
+}
+
 static void VULKAN_BeginCopyPass(
 	Refresh_Renderer *driverData,
 	Refresh_CommandBuffer *commandBuffer
@@ -8362,7 +8550,7 @@ static void VULKAN_UploadToTexture(
 ) {
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
 	VulkanCommandBuffer *vulkanCommandBuffer = (VulkanCommandBuffer*) commandBuffer;
-	VulkanBuffer *vulkanCpuBuffer = (VulkanBuffer*) cpuBuffer;
+	VulkanCpuBufferContainer *bufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
 	VulkanTexture *vulkanTexture = ((VulkanTextureContainer*) textureSlice->texture)->vulkanTexture;
 	VkBufferImageCopy imageCopy;
 
@@ -8370,7 +8558,7 @@ static void VULKAN_UploadToTexture(
 		renderer,
 		vulkanCommandBuffer->commandBuffer,
 		RESOURCE_ACCESS_TRANSFER_READ,
-		vulkanCpuBuffer
+		bufferContainer->activeBuffer->vulkanBuffer
 	);
 
 	VULKAN_INTERNAL_ImageMemoryBarrier(
@@ -8403,14 +8591,14 @@ static void VULKAN_UploadToTexture(
 
 	renderer->vkCmdCopyBufferToImage(
 		vulkanCommandBuffer->commandBuffer,
-		vulkanCpuBuffer->buffer,
+		bufferContainer->activeBuffer->vulkanBuffer->buffer,
 		vulkanTexture->image,
 		AccessMap[vulkanTexture->resourceAccessType].imageLayout,
 		1,
 		&imageCopy
 	);
 
-	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanCpuBuffer);
+	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, bufferContainer->activeBuffer->vulkanBuffer);
 	VULKAN_INTERNAL_TrackTexture(renderer, vulkanCommandBuffer, vulkanTexture);
 	VULKAN_INTERNAL_TrackCopiedTexture(renderer, vulkanCommandBuffer, vulkanTexture);
 }
@@ -8424,7 +8612,7 @@ static void VULKAN_UploadToBuffer(
 ) {
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
 	VulkanCommandBuffer *vulkanCommandBuffer = (VulkanCommandBuffer*) commandBuffer;
-	VulkanBuffer *vulkanCpuBuffer = (VulkanBuffer*) cpuBuffer;
+	VulkanCpuBufferContainer *cpuBufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
 	VulkanBuffer *vulkanGpuBuffer = ((VulkanBufferContainer*) gpuBuffer)->vulkanBuffer;
 	VkBufferCopy bufferCopy;
 
@@ -8432,7 +8620,7 @@ static void VULKAN_UploadToBuffer(
 		renderer,
 		vulkanCommandBuffer->commandBuffer,
 		RESOURCE_ACCESS_TRANSFER_READ,
-		vulkanCpuBuffer
+		cpuBufferContainer->activeBuffer->vulkanBuffer
 	);
 
 	VULKAN_INTERNAL_BufferMemoryBarrier(
@@ -8448,13 +8636,13 @@ static void VULKAN_UploadToBuffer(
 
 	renderer->vkCmdCopyBuffer(
 		vulkanCommandBuffer->commandBuffer,
-		vulkanCpuBuffer->buffer,
+		cpuBufferContainer->activeBuffer->vulkanBuffer->buffer,
 		vulkanGpuBuffer->buffer,
 		1,
 		&bufferCopy
 	);
 
-	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanCpuBuffer);
+	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, cpuBufferContainer->activeBuffer->vulkanBuffer);
 	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanGpuBuffer);
 	VULKAN_INTERNAL_TrackCopiedBuffer(renderer, vulkanCommandBuffer, vulkanGpuBuffer);
 }
@@ -8469,14 +8657,14 @@ static void VULKAN_DownloadFromTexture(
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
 	VulkanCommandBuffer *vulkanCommandBuffer = (VulkanCommandBuffer*) commandBuffer;
 	VulkanTexture *vulkanTexture = ((VulkanTextureContainer*) textureSlice->texture)->vulkanTexture;
-	VulkanBuffer *vulkanCpuBuffer = (VulkanBuffer*) cpuBuffer;
+	VulkanCpuBufferContainer *cpuBufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
 	VkBufferImageCopy imageCopy;
 
 	VULKAN_INTERNAL_BufferMemoryBarrier(
 		renderer,
 		vulkanCommandBuffer->commandBuffer,
 		RESOURCE_ACCESS_TRANSFER_WRITE,
-		vulkanCpuBuffer
+		cpuBufferContainer->activeBuffer->vulkanBuffer
 	);
 
 	VULKAN_INTERNAL_ImageMemoryBarrier(
@@ -8511,14 +8699,16 @@ static void VULKAN_DownloadFromTexture(
 		vulkanCommandBuffer->commandBuffer,
 		vulkanTexture->image,
 		AccessMap[vulkanTexture->resourceAccessType].imageLayout,
-		vulkanCpuBuffer->buffer,
+		cpuBufferContainer->activeBuffer->vulkanBuffer->buffer,
 		1,
 		&imageCopy
 	);
 
-	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanCpuBuffer);
+	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, cpuBufferContainer->activeBuffer->vulkanBuffer);
 	VULKAN_INTERNAL_TrackTexture(renderer, vulkanCommandBuffer, vulkanTexture);
 	VULKAN_INTERNAL_TrackCopiedTexture(renderer, vulkanCommandBuffer, vulkanTexture);
+
+	cpuBufferContainer->activeBuffer->vulkanBuffer->preserveContentsOnDefrag = 1;
 }
 
 static void VULKAN_DownloadFromBuffer(
@@ -8530,7 +8720,7 @@ static void VULKAN_DownloadFromBuffer(
 ) {
 	VulkanRenderer *renderer = (VulkanRenderer*) driverData;
 	VulkanCommandBuffer *vulkanCommandBuffer = (VulkanCommandBuffer*) commandBuffer;
-	VulkanBuffer *vulkanCpuBuffer = (VulkanBuffer*) cpuBuffer;
+	VulkanCpuBufferContainer *cpuBufferContainer = (VulkanCpuBufferContainer*) cpuBuffer;
 	VulkanBuffer *vulkanGpuBuffer = ((VulkanBufferContainer*) gpuBuffer)->vulkanBuffer;
 	VkBufferCopy bufferCopy;
 
@@ -8538,7 +8728,7 @@ static void VULKAN_DownloadFromBuffer(
 		renderer,
 		vulkanCommandBuffer->commandBuffer,
 		RESOURCE_ACCESS_TRANSFER_WRITE,
-		vulkanCpuBuffer
+		cpuBufferContainer->activeBuffer->vulkanBuffer
 	);
 
 	VULKAN_INTERNAL_BufferMemoryBarrier(
@@ -8555,14 +8745,16 @@ static void VULKAN_DownloadFromBuffer(
 	renderer->vkCmdCopyBuffer(
 		vulkanCommandBuffer->commandBuffer,
 		vulkanGpuBuffer->buffer,
-		vulkanCpuBuffer->buffer,
+		cpuBufferContainer->activeBuffer->vulkanBuffer->buffer,
 		1,
 		&bufferCopy
 	);
 
-	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanCpuBuffer);
+	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, cpuBufferContainer->activeBuffer->vulkanBuffer);
 	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanGpuBuffer);
 	VULKAN_INTERNAL_TrackBuffer(renderer, vulkanCommandBuffer, vulkanGpuBuffer);
+
+	cpuBufferContainer->activeBuffer->vulkanBuffer->preserveContentsOnDefrag = 1;
 }
 
 static void VULKAN_CopyTextureToTexture(
@@ -10118,7 +10310,7 @@ static uint8_t VULKAN_INTERNAL_DefragmentMemory(
 			currentRegion = allocation->usedRegions[i];
 			copyResourceAccessType = RESOURCE_ACCESS_NONE;
 
-			if (currentRegion->isBuffer)
+			if (currentRegion->isBuffer && !currentRegion->vulkanBuffer->markedForDestroy)
 			{
 				currentRegion->vulkanBuffer->usage |= VK_BUFFER_USAGE_TRANSFER_DST_BIT;
 
@@ -10130,7 +10322,8 @@ static uint8_t VULKAN_INTERNAL_DefragmentMemory(
 					currentRegion->vulkanBuffer->requireHostVisible,
 					currentRegion->vulkanBuffer->requireHostLocal,
 					currentRegion->vulkanBuffer->preferDeviceLocal,
-					0
+					0,
+					currentRegion->vulkanBuffer->preserveContentsOnDefrag
 				);
 
 				if (newBuffer == NULL)
@@ -10139,43 +10332,47 @@ static uint8_t VULKAN_INTERNAL_DefragmentMemory(
 					return 0;
 				}
 
-				originalResourceAccessType = currentRegion->vulkanBuffer->resourceAccessType;
+				/* Copy buffer contents if necessary */
+				if (currentRegion->vulkanBuffer->preserveContentsOnDefrag)
+				{
+					originalResourceAccessType = currentRegion->vulkanBuffer->resourceAccessType;
 
-				VULKAN_INTERNAL_BufferMemoryBarrier(
+					VULKAN_INTERNAL_BufferMemoryBarrier(
-					renderer,
+						renderer,
-					commandBuffer->commandBuffer,
+						commandBuffer->commandBuffer,
-					RESOURCE_ACCESS_TRANSFER_READ,
+						RESOURCE_ACCESS_TRANSFER_READ,
-					currentRegion->vulkanBuffer
+						currentRegion->vulkanBuffer
-				);
+					);
 
-				VULKAN_INTERNAL_BufferMemoryBarrier(
+					VULKAN_INTERNAL_BufferMemoryBarrier(
-					renderer,
+						renderer,
-					commandBuffer->commandBuffer,
+						commandBuffer->commandBuffer,
-					RESOURCE_ACCESS_TRANSFER_WRITE,
+						RESOURCE_ACCESS_TRANSFER_WRITE,
-					newBuffer
+						newBuffer
-				);
+					);
 
-				bufferCopy.srcOffset = 0;
+					bufferCopy.srcOffset = 0;
-				bufferCopy.dstOffset = 0;
+					bufferCopy.dstOffset = 0;
-				bufferCopy.size = currentRegion->resourceSize;
+					bufferCopy.size = currentRegion->resourceSize;
 
-				renderer->vkCmdCopyBuffer(
+					renderer->vkCmdCopyBuffer(
-					commandBuffer->commandBuffer,
+						commandBuffer->commandBuffer,
-					currentRegion->vulkanBuffer->buffer,
+						currentRegion->vulkanBuffer->buffer,
-					newBuffer->buffer,
+						newBuffer->buffer,
-					1,
+						1,
-					&bufferCopy
+						&bufferCopy
-				);
+					);
 
-				VULKAN_INTERNAL_BufferMemoryBarrier(
+					VULKAN_INTERNAL_BufferMemoryBarrier(
-					renderer,
+						renderer,
-					commandBuffer->commandBuffer,
+						commandBuffer->commandBuffer,
-					originalResourceAccessType,
+						originalResourceAccessType,
-					newBuffer
+						newBuffer
-				);
+					);
 
-				VULKAN_INTERNAL_TrackBuffer(renderer, commandBuffer, currentRegion->vulkanBuffer);
+					VULKAN_INTERNAL_TrackBuffer(renderer, commandBuffer, currentRegion->vulkanBuffer);
-				VULKAN_INTERNAL_TrackBuffer(renderer, commandBuffer, newBuffer);
+					VULKAN_INTERNAL_TrackBuffer(renderer, commandBuffer, newBuffer);
+				}
 
 				/* re-point original container to new buffer */
 				if (currentRegion->vulkanBuffer->container != NULL)
@@ -10189,7 +10386,7 @@ static uint8_t VULKAN_INTERNAL_DefragmentMemory(
 
 				renderer->needDefrag = 1;
 			}
-			else
+			else if (!currentRegion->vulkanTexture->markedForDestroy)
 			{
 				newTexture = VULKAN_INTERNAL_CreateTexture(
 					renderer,