Create the texture from OpenEXR

D3D12HelloEXR.cpp

// Create the texture from OpenEXR
{
	DirectX::TexMetadata metaData;
	DirectX::ScratchImage scratchImage;
	ThrowIfFailed(LoadFromEXRFile(L"exrtest.exr", &metaData, scratchImage));

	const size_t subresoucesize = metaData.mipLevels;
	const size_t uploadBufferSize = scratchImage.GetPixelsSize();

	D3D12_RESOURCE_DESC textureDesc = {};
	textureDesc.Width = metaData.width;
	textureDesc.Height = static_cast<UINT>(metaData.height);
	textureDesc.MipLevels = static_cast<UINT16>(subresoucesize);
	textureDesc.Format = metaData.format;
	textureDesc.DepthOrArraySize = static_cast<UINT16>( metaData.arraySize );
	textureDesc.SampleDesc.Quality = 0;
	textureDesc.SampleDesc.Count = 1;
	textureDesc.Dimension = D3D12_RESOURCE_DIMENSION_TEXTURE2D;
	textureDesc.Flags = D3D12_RESOURCE_FLAG_NONE;

	ThrowIfFailed(m_device->CreateCommittedResource(
		&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT),
		D3D12_HEAP_FLAG_NONE,
		&textureDesc,
		D3D12_RESOURCE_STATE_COPY_DEST,
		nullptr,
		IID_PPV_ARGS(&m_texture)));

	// Create the GPU upload buffer.
	ThrowIfFailed(m_device->CreateCommittedResource(
		&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_UPLOAD),
		D3D12_HEAP_FLAG_NONE,
		&CD3DX12_RESOURCE_DESC::Buffer(uploadBufferSize),
		D3D12_RESOURCE_STATE_GENERIC_READ,
		nullptr,
		IID_PPV_ARGS(&textureUploadHeap)));

	std::vector<D3D12_SUBRESOURCE_DATA> subresouceData;
	for (size_t i = 0; i < subresoucesize; i++)
	{
		D3D12_SUBRESOURCE_DATA subresouce;

		subresouce.pData = scratchImage.GetImages()[i].pixels;
		subresouce.RowPitch = scratchImage.GetImages()[i].rowPitch;
		subresouce.SlicePitch = scratchImage.GetImages()[i].slicePitch;

		subresouceData.push_back(subresouce);
	}

	UpdateSubresources(m_commandList.Get(), m_texture.Get(), textureUploadHeap.Get(), 0, 0, static_cast<UINT>(subresoucesize), &subresouceData[0]);
	m_commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(m_texture.Get(), D3D12_RESOURCE_STATE_COPY_DEST, D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE));

	// Describe and create a SRV for the texture.
	D3D12_SHADER_RESOURCE_VIEW_DESC srvDesc = {};
	srvDesc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;
	srvDesc.Format = textureDesc.Format;
	srvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2D;
	srvDesc.Texture2D.MipLevels = static_cast<UINT>(subresoucesize);
	m_device->CreateShaderResourceView(m_texture.Get(), &srvDesc, m_srvHeap->GetCPUDescriptorHandleForHeapStart());

	m_commandList->DiscardResource(textureUploadHeap.Get(), nullptr);
}