Files
UnrealEngine/Engine/Plugins/PCG/Shaders/Private/BuiltInKernels/PCGDataNum.usf
2025-05-18 13:04:45 +08:00

32 lines
1.0 KiB
HLSL

// Copyright Epic Games, Inc. All Rights Reserved.
// Returns the total data count
[numthreads(64, 1, 1)]
void PCGDataNumCS(uint3 GroupId : SV_GroupID, uint GroupIndex : SV_GroupIndex)
{
// Mark the kernel as having executed. Must run before we early out via thread index, because the kernel is still 'executed' even if the number of
// threads to iterate on is zero. Even if GetNumThreads() returns 0, the kernel will still have been dispatched on a single thread to set this flag.
if (all(GroupId == 0) && GroupIndex == 0)
{
Out_SetAsExecutedInternal();
}
const uint ThreadIndex = GetUnWrappedDispatchThreadId(GroupId, GroupIndex, 64);
if (ThreadIndex >= GetNumThreads().x) return;
uint InDataIndex, InElemIndex;
if (!In_GetThreadData(ThreadIndex, InDataIndex, InElemIndex))
{
return;
}
uint OutDataIndex, OutElemIndex;
if (!Out_GetThreadData(ThreadIndex, OutDataIndex, OutElemIndex))
{
return;
}
const int AttributeId = DataNum_GetOutputAttributeId();
Out_SetInt(OutDataIndex, OutElemIndex, AttributeId, (int)In_GetNumData());
}