Files
UnrealEngine/Engine/Shaders/Private/Nanite/NaniteStreaming.ush
Brandyn / Techy fcc1b09210 init
2026-04-04 15:40:51 -05:00

49 lines
2.0 KiB
HLSL

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include "../Common.ush"
#include "../WaveOpUtil.ush"
#include "/Engine/Shared/NaniteDefinitions.h"
struct FStreamingRequest
{
uint RuntimeResourceID_Magic;
uint ResourcePageRangeKey;
uint Priority_Magic;
};
uint StreamingRequestsBufferVersion;
uint StreamingRequestsBufferSize;
void RequestPageRange( RWStructuredBuffer<FStreamingRequest> RequestsBuffer, uint RuntimeResourceID, uint ResourcePageRangeKey, uint PriorityCategory, float Priority )
{
const uint NumPagesOrPageRanges = ResourcePageRangeKey & NANITE_PAGE_RANGE_KEY_COUNT_MASK;
const bool bHasStreamingPages = (ResourcePageRangeKey & NANITE_PAGE_RANGE_KEY_FLAG_HAS_STREAMING_PAGES) != 0;
if ((RenderFlags & NANITE_RENDER_FLAG_OUTPUT_STREAMING_REQUESTS) && NumPagesOrPageRanges > 0 && bHasStreamingPages)
{
uint Index;
WaveInterlockedAddScalar_(RequestsBuffer[0].RuntimeResourceID_Magic, 1, Index); // HACK: Store count in RuntimeResourceID_Magic of first request.
if (Index < StreamingRequestsBufferSize - 1)
{
const uint MinPriority = NANITE_SANITY_CHECK_STREAMING_REQUESTS ? (1u << NANITE_STREAMING_REQUEST_MAGIC_BITS) : 1u;
const uint UIntPriority = clamp((PriorityCategory << 30) | (asuint(Priority) >> 2), MinPriority, NANITE_MAX_PRIORITY_BEFORE_PARENTS);
FStreamingRequest Request;
#if NANITE_SANITY_CHECK_STREAMING_REQUESTS
Request.RuntimeResourceID_Magic = (RuntimeResourceID << NANITE_STREAMING_REQUEST_MAGIC_BITS);
Request.ResourcePageRangeKey = ResourcePageRangeKey;
Request.Priority_Magic = UIntPriority & ~NANITE_STREAMING_REQUEST_MAGIC_MASK; // Mask off low bits to leave space for magic
const uint FrameNibble = StreamingRequestsBufferVersion & 0xF;
Request.RuntimeResourceID_Magic |= 0x10 | FrameNibble;
Request.Priority_Magic |= 0x20 | FrameNibble;
#else
Request.RuntimeResourceID_Magic = RuntimeResourceID;
Request.ResourcePageRangeKey = ResourcePageRangeKey;
Request.Priority_Magic = UIntPriority;
#endif
RequestsBuffer[Index + 1] = Request;
}
}
}