Add implementations for resolveResource() to D3D12 and Vulkan backends (#2094)

* Added implementations for resolveResource to both D3D and Vulkan backends

* Simple test for resolving a multisampled resource written and confirmed to run successfully for D3D12

* Fixed a bug preventing MSAA from working in Vulkan

* Changed test format to RGBA32 Float (because swiftshader)

1 files changed, 34 insertions, 5 deletions

diff --git a/tools/gfx/d3d12/render-d3d12.cpp b/tools/gfx/d3d12/render-d3d12.cpp
index e0c324d34..1b146bc4e 100644
--- a/tools/gfx/d3d12/render-d3d12.cpp
+++ b/tools/gfx/d3d12/render-d3d12.cpp
@@ -4314,15 +4314,44 @@ public:
 
             virtual SLANG_NO_THROW void SLANG_MCALL resolveResource(
                 ITextureResource* source,
+                ResourceState sourceState,
                 SubresourceRange sourceRange,
                 ITextureResource* dest,
+                ResourceState destState,
                 SubresourceRange destRange) override
             {
-                SLANG_UNUSED(source);
-                SLANG_UNUSED(sourceRange);
-                SLANG_UNUSED(dest);
-                SLANG_UNUSED(destRange);
-                SLANG_UNIMPLEMENTED_X("resolveResource");
+                auto srcTexture = static_cast<TextureResourceImpl*>(source);
+                auto srcDesc = srcTexture->getDesc();
+                auto dstTexture = static_cast<TextureResourceImpl*>(dest);
+                auto dstDesc = dstTexture->getDesc();
+
+                for (uint32_t layer = 0; layer < sourceRange.layerCount; ++layer)
+                {
+                    for (uint32_t mip = 0; mip < sourceRange.mipLevelCount; ++mip)
+                    {
+                        auto srcSubresourceIndex = D3DUtil::getSubresourceIndex(
+                            mip + sourceRange.mipLevel,
+                            layer + sourceRange.baseArrayLayer,
+                            0,
+                            srcDesc->numMipLevels,
+                            srcDesc->arraySize);
+                        auto dstSubresourceIndex = D3DUtil::getSubresourceIndex(
+                            mip + destRange.mipLevel,
+                            layer + destRange.baseArrayLayer,
+                            0,
+                            dstDesc->numMipLevels,
+                            dstDesc->arraySize);
+
+                        DXGI_FORMAT format = D3DUtil::getMapFormat(srcDesc->format);
+
+                        m_commandBuffer->m_cmdList->ResolveSubresource(
+                            dstTexture->m_resource.getResource(),
+                            dstSubresourceIndex,
+                            srcTexture->m_resource.getResource(),
+                            srcSubresourceIndex,
+                            format);
+                    }
+                }
             }
 
             virtual SLANG_NO_THROW void SLANG_MCALL copyTextureToBuffer(