[d3d11] Re-implement direct image mapping (disabled by default)

We cannot enable this by default yet because it may break some games.

src/d3d11/d3d11_context_imm.cpp

@@ -189,13 +189,30 @@ namespace dxvk {
     if (pMappedResource == nullptr)
       return S_FALSE;
     
+    // Parameter validation was successful
     VkImageSubresource subresource =
       pResource->GetSubresourceFromIndex(
         VK_IMAGE_ASPECT_COLOR_BIT, Subresource);
     
     pResource->SetMappedSubresource(subresource);
     
-    // Query format info in order to compute
+    if (pResource->GetMapMode() == D3D11_COMMON_TEXTURE_MAP_MODE_DIRECT) {
+      const VkImageType imageType = mappedImage->info().type;
+      
+      // Wait for the resource to become available
+      if (!WaitForResource(mappedImage, MapFlags))
+        return DXGI_ERROR_WAS_STILL_DRAWING;
+      
+      // Query the subresource's memory layout and hope that
+      // the application respects the returned pitch values.
+      VkSubresourceLayout layout = mappedImage->querySubresourceLayout(subresource);
+      
+      pMappedResource->pData      = mappedImage->mapPtr(layout.offset);
+      pMappedResource->RowPitch   = imageType >= VK_IMAGE_TYPE_2D ? layout.rowPitch   : layout.size;
+      pMappedResource->DepthPitch = imageType >= VK_IMAGE_TYPE_3D ? layout.depthPitch : layout.size;
+      return S_OK;
+    } else {
+      // Query format info which we need to compute
       // the row pitch and layer pitch properly.
       const DxvkFormatInfo* formatInfo = imageFormatInfo(mappedImage->info().format);
       
@@ -205,9 +222,9 @@ namespace dxvk {
       
       DxvkPhysicalBufferSlice physicalSlice;
       
-    // When using any map mode which requires the image contents
-    // to be preserved, copy the image's contents into the buffer.
       if (MapType == D3D11_MAP_WRITE_DISCARD) {
+        // We do not have to preserve the contents of the
+        // buffer if the entire image gets discarded.
         physicalSlice = mappedBuffer->allocPhysicalSlice();
         physicalSlice.resource()->acquire();
         
@@ -219,8 +236,9 @@ namespace dxvk {
           cPhysicalSlice.resource()->release();
         });
       } else {
-      // We may have to copy the current image contents into the
+        // When using any map mode which requires the image contents
-      // mapped buffer if the GPU has write access to the image.
+        // to be preserved, and if the GPU has write access to the
+        // image, copy the current image contents into the buffer.
         const bool copyExistingData = pResource->Desc()->Usage == D3D11_USAGE_STAGING;
         
         if (copyExistingData) {
@@ -254,6 +272,7 @@ namespace dxvk {
       pMappedResource->DepthPitch = formatInfo->elementSize * blockCount.width * blockCount.height;
       return S_OK;
     }
+  }
   
   
   void D3D11ImmediateContext::UnmapImage(
@@ -286,6 +305,8 @@ namespace dxvk {
           cSrcBuffer, 0, { 0u, 0u });
       });
     }
+    
+    pResource->ClearMappedSubresource();
   }
   
   

src/d3d11/d3d11_texture.cpp

@@ -203,7 +203,7 @@ namespace dxvk {
     // 2. Since the image will most likely be read for rendering by the GPU,
     //    writing the image to device-local image may be more efficient than
     //    reading its contents from host-visible memory.
-    if ((m_desc.CPUAccessFlags & D3D11_CPU_ACCESS_READ) == 0)
+    if (m_desc.Usage == D3D11_USAGE_DYNAMIC)
       return D3D11_COMMON_TEXTURE_MAP_MODE_BUFFER;
     
     // Images that can be read by the host should be mapped directly in