For now, handle persistent maps during capture by forcing flush

* This is ugly and will change once maps are properly intercepted, but
  works for now.

renderdoc/common/common.cpp

@@ -164,7 +164,7 @@ bool FindDiffRange(void *a, void *b, size_t bufSize, size_t &diffStart, size_t &
 	// do we have some unaligned bytes at the end of the buffer?
 	if(bufSize > alignedSize)
 	{
-		size_t numBytes = alignedSize-bufSize;
+		size_t numBytes = bufSize-alignedSize;
 
 		// if we haven't even found a start, check in these bytes
 		if(diffStart > bufSize)

renderdoc/driver/vulkan/vk_resources.h

@@ -703,13 +703,15 @@ struct VkResourceRecord : public ResourceRecord
 struct MemState
 {
 	MemState()
-		: mapOffset(0), mapSize(0), size(0), mapFlags(0), mappedPtr(0), mapFlushed(false)
+		: device(VK_NULL_HANDLE), mapOffset(0), mapSize(0), size(0), mapFlags(0), mappedPtr(NULL), mapFlushed(false), refData(NULL)
 	{ }
+	VkDevice device;
 	VkDeviceSize mapOffset, mapSize;
 	VkDeviceSize size;
 	VkMemoryMapFlags mapFlags;
 	bool mapFlushed;
 	void *mappedPtr;
+	byte *refData;
 };
 struct ImgState
 {

renderdoc/driver/vulkan/wrappers/vk_queue_funcs.cpp

@@ -339,6 +339,42 @@ VkResult WrappedVulkan::vkQueueSubmit(
 		m_FrameCaptureRecord->AddChunk(scope.Get());
 	}
 
+	// VKTODOHIGH when maps are intercepted with local buffers, this will have to be
+	// done when not in capframe :(.
+	if(m_State == WRITING_CAPFRAME)
+	{
+		for(auto it = m_MemoryInfo.begin(); it != m_MemoryInfo.end(); ++it)
+		{
+			// potential persistent map, force a full flush
+			if(it->second.mappedPtr)
+			{
+				size_t diffStart = 0, diffEnd = 0;
+				bool found = true;
+
+				// if we have a previous set of data, compare.
+				// otherwise just serialise it all
+				if(it->second.refData)
+					found = FindDiffRange((byte *)it->second.mappedPtr, it->second.refData, (size_t)it->second.mapSize, diffStart, diffEnd);
+				else
+					diffEnd = (size_t)it->second.mapSize;
+
+				if(found)
+				{
+					{
+						RDCLOG("Persistent map flush forced for %llu (%llu -> %llu)", it->first, (uint64_t)diffStart, (uint64_t)diffEnd);
+						VkMappedMemoryRange range = { VK_STRUCTURE_TYPE_MAPPED_MEMORY_RANGE, NULL, GetResourceManager()->GetCurrentHandle<VkDeviceMemory>(it->first), it->second.mapOffset+diffStart, diffEnd-diffStart };
+						vkFlushMappedMemoryRanges(it->second.device, 1, &range);
+					}
+
+					// allocate ref data so we can compare next time to minimise serialised data
+					if(it->second.refData == NULL)
+						it->second.refData = new byte[it->second.mapSize];
+					memcpy(it->second.refData, it->second.mappedPtr, (size_t)it->second.mapSize);
+				}
+			}
+		}
+	}
+
 	for(uint32_t i=0; i < cmdBufferCount; i++)
 	{
 		ResourceId cmd = GetResID(pCmdBuffers[i]);

renderdoc/driver/vulkan/wrappers/vk_resource_funcs.cpp

@@ -98,6 +98,7 @@ VkResult WrappedVulkan::vkAllocMemory(
 			GetResourceManager()->AddLiveResource(id, *pMem);
 		}
 
+		m_MemoryInfo[id].device = device;
 		m_MemoryInfo[id].size = pAllocInfo->allocationSize;
 	}
 
@@ -150,6 +151,7 @@ VkResult WrappedVulkan::vkMapMemory(
 				it->second.mapSize = size == 0 ? it->second.size : size;
 				it->second.mapFlags = flags;
 				it->second.mapFlushed = false;
+				it->second.refData = NULL;
 			}
 		}
 		else if(m_State >= WRITING)
@@ -263,6 +265,7 @@ VkResult WrappedVulkan::vkUnmapMemory(
 				}
 
 				it->second.mappedPtr = NULL;
+				SAFE_DELETE_ARRAY(it->second.refData);
 			}
 		}
 	}