FUnorderedAccessViewRHIRef FD3D12DynamicRHI::RHICreateUnorderedAccessView(FStructuredBufferRHIParamRef StructuredBufferRHI, bool bUseUAVCounter, bool bAppendBuffer)
{
FD3D12StructuredBuffer* StructuredBuffer = FD3D12DynamicRHI::ResourceCast(StructuredBufferRHI);
const D3D12_RESOURCE_DESC& BufferDesc = StructuredBuffer->Resource->GetDesc();
const uint32 BufferUsage = StructuredBuffer->GetUsage();
const bool bByteAccessBuffer = (BufferUsage & BUF_ByteAddressBuffer) != 0;
const bool bStructuredBuffer = !bByteAccessBuffer;
check(bByteAccessBuffer != bStructuredBuffer); // You can't have a structured buffer that allows raw views
D3D12_UNORDERED_ACCESS_VIEW_DESC UAVDesc ={};
UAVDesc.ViewDimension = D3D12_UAV_DIMENSION_BUFFER;
UAVDesc.Format = DXGI_FORMAT_UNKNOWN;
uint32 EffectiveStride = StructuredBuffer->GetStride();
if (bByteAccessBuffer)
{
UAVDesc.Format = DXGI_FORMAT_R32_TYPELESS;
EffectiveStride = 4;
}
else if (BufferUsage & BUF_DrawIndirect)
{
UAVDesc.Format = DXGI_FORMAT_R32_UINT;
EffectiveStride = 4;
}
UAVDesc.Buffer.FirstElement = StructuredBuffer->ResourceLocation->GetOffset() / EffectiveStride;
UAVDesc.Buffer.NumElements = StructuredBuffer->ResourceLocation->GetEffectiveBufferSize() / EffectiveStride;
UAVDesc.Buffer.StructureByteStride = bStructuredBuffer ? EffectiveStride : 0;
UAVDesc.Buffer.Flags = D3D12_BUFFER_UAV_FLAG_NONE;
UAVDesc.Buffer.CounterOffsetInBytes = 0;
const bool bNeedsCounterResource = bAppendBuffer | bUseUAVCounter;
TRefCountPtr<FD3D12Resource> CounterResource;
if (bNeedsCounterResource)
{
GetRHIDevice()->GetResourceHelper().CreateBuffer(D3D12_HEAP_TYPE_DEFAULT, 4, CounterResource.GetInitReference(), D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS);
}
if (bByteAccessBuffer)
{
UAVDesc.Buffer.Flags |= D3D12_BUFFER_UAV_FLAG_RAW;
}
return new FD3D12UnorderedAccessView(GetRHIDevice(), &UAVDesc, StructuredBuffer->ResourceLocation, CounterResource);
}
FUnorderedAccessViewRHIRef FD3D12DynamicRHI::RHICreateUnorderedAccessView(FStructuredBufferRHIParamRef StructuredBufferRHI, bool bUseUAVCounter, bool bAppendBuffer)
{
FD3D12StructuredBuffer* StructuredBuffer = FD3D12DynamicRHI::ResourceCast(StructuredBufferRHI);
FD3D12ResourceLocation& Location = StructuredBuffer->ResourceLocation;
const D3D12_RESOURCE_DESC& BufferDesc = Location.GetResource()->GetDesc();
const uint32 BufferUsage = StructuredBuffer->GetUsage();
const bool bByteAccessBuffer = (BufferUsage & BUF_ByteAddressBuffer) != 0;
const bool bStructuredBuffer = !bByteAccessBuffer;
check(bByteAccessBuffer != bStructuredBuffer); // You can't have a structured buffer that allows raw views
D3D12_UNORDERED_ACCESS_VIEW_DESC UAVDesc = {};
UAVDesc.ViewDimension = D3D12_UAV_DIMENSION_BUFFER;
UAVDesc.Format = DXGI_FORMAT_UNKNOWN;
uint32 EffectiveStride = StructuredBuffer->GetStride();
if (bByteAccessBuffer)
{
UAVDesc.Format = DXGI_FORMAT_R32_TYPELESS;
EffectiveStride = 4;
}
else if (BufferUsage & BUF_DrawIndirect)
{
UAVDesc.Format = DXGI_FORMAT_R32_UINT;
EffectiveStride = 4;
}
UAVDesc.Buffer.FirstElement = Location.GetOffsetFromBaseOfResource() / EffectiveStride;
UAVDesc.Buffer.NumElements = Location.GetSize() / EffectiveStride;
UAVDesc.Buffer.StructureByteStride = bStructuredBuffer ? EffectiveStride : 0;
UAVDesc.Buffer.Flags = D3D12_BUFFER_UAV_FLAG_NONE;
UAVDesc.Buffer.CounterOffsetInBytes = 0;
const bool bNeedsCounterResource = bAppendBuffer | bUseUAVCounter;
if (bByteAccessBuffer)
{
UAVDesc.Buffer.Flags |= D3D12_BUFFER_UAV_FLAG_RAW;
}
return CreateUAV(UAVDesc, StructuredBuffer, bNeedsCounterResource);
}