void FSceneRenderer::InitFogConstants()
{
// console command override
float FogDensityOverride = -1.0f;
float FogStartDistanceOverride = -1.0f;
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
{
// console variable overrides
FogDensityOverride = CVarFogDensity.GetValueOnAnyThread();
FogStartDistanceOverride = CVarFogStartDistance.GetValueOnAnyThread();
}
#endif // !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
for(int32 ViewIndex = 0;ViewIndex < Views.Num();ViewIndex++)
{
FViewInfo& View = Views[ViewIndex];
// set fog consts based on height fog components
if(ShouldRenderFog(*View.Family))
{
if (Scene->ExponentialFogs.Num() > 0)
{
const FExponentialHeightFogSceneInfo& FogInfo = Scene->ExponentialFogs[0];
const float CosTerminatorAngle = FMath::Clamp(FMath::Cos(FogInfo.LightTerminatorAngle * PI / 180.0f), -1.0f + DELTA, 1.0f - DELTA);
const float CollapsedFogParameterPower = FMath::Clamp(
-FogInfo.FogHeightFalloff * (View.ViewMatrices.ViewOrigin.Z - FogInfo.FogHeight),
-126.f + 1.f, // min and max exponent values for IEEE floating points (http://en.wikipedia.org/wiki/IEEE_floating_point)
+127.f - 1.f
);
const float CollapsedFogParameter = FogInfo.FogDensity * FMath::Pow(2.0f, CollapsedFogParameterPower);
View.ExponentialFogParameters = FVector4(CollapsedFogParameter, FogInfo.FogHeightFalloff, CosTerminatorAngle, FogInfo.StartDistance);
View.ExponentialFogColor = FVector(FogInfo.FogColor.R, FogInfo.FogColor.G, FogInfo.FogColor.B);
View.FogMaxOpacity = FogInfo.FogMaxOpacity;
View.DirectionalInscatteringExponent = FogInfo.DirectionalInscatteringExponent;
View.DirectionalInscatteringStartDistance = FogInfo.DirectionalInscatteringStartDistance;
View.bUseDirectionalInscattering = false;
View.InscatteringLightDirection = FVector(0);
for (TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Scene->Lights); It; ++It)
{
const FLightSceneInfoCompact& LightInfo = *It;
// This will find the first directional light that is set to be used as an atmospheric sun light of sufficient brightness.
// If you have more than one directional light with these properties then all subsequent lights will be ignored.
if (LightInfo.LightSceneInfo->Proxy->GetLightType() == LightType_Directional
&& LightInfo.LightSceneInfo->Proxy->IsUsedAsAtmosphereSunLight()
&& LightInfo.LightSceneInfo->Proxy->GetColor().ComputeLuminance() > KINDA_SMALL_NUMBER
&& FogInfo.DirectionalInscatteringColor.ComputeLuminance() > KINDA_SMALL_NUMBER)
{
View.InscatteringLightDirection = -LightInfo.LightSceneInfo->Proxy->GetDirection();
View.bUseDirectionalInscattering = true;
View.DirectionalInscatteringColor = FogInfo.DirectionalInscatteringColor * LightInfo.LightSceneInfo->Proxy->GetColor().ComputeLuminance();
break;
}
}
}
}
}
}
/**
* Renders the view family.
*/
void FDeferredShadingSceneRenderer::Render()
{
if(!ViewFamily.EngineShowFlags.Rendering)
{
return;
}
SCOPED_DRAW_EVENT(Scene,DEC_SCENE_ITEMS);
// Initialize global system textures (pass-through if already initialized).
GSystemTextures.InitializeTextures();
// Allocate the maximum scene render target space for the current view family.
GSceneRenderTargets.Allocate(ViewFamily);
// Find the visible primitives.
InitViews();
const bool bIsWireframe = ViewFamily.EngineShowFlags.Wireframe;
static const auto ClearMethodCVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.ClearSceneMethod"));
bool bRequiresRHIClear = true;
bool bRequiresFarZQuadClear = false;
if (ClearMethodCVar)
{
switch (ClearMethodCVar->GetValueOnRenderThread())
{
case 0: // No clear
{
bRequiresRHIClear = false;
bRequiresFarZQuadClear = false;
break;
}
case 1: // RHIClear
{
bRequiresRHIClear = true;
bRequiresFarZQuadClear = false;
break;
}
case 2: // Clear using far-z quad
{
bRequiresFarZQuadClear = true;
bRequiresRHIClear = false;
break;
}
}
}
// Always perform a full buffer clear for wireframe, shader complexity view mode, and stationary light overlap viewmode.
if (bIsWireframe || ViewFamily.EngineShowFlags.ShaderComplexity || ViewFamily.EngineShowFlags.StationaryLightOverlap)
{
bRequiresRHIClear = true;
}
// force using occ queries for wireframe if rendering is parented or frozen in the first view
check(Views.Num());
#if (UE_BUILD_SHIPPING || UE_BUILD_TEST)
const bool bIsViewFrozen = false;
const bool bHasViewParent = false;
#else
const bool bIsViewFrozen = Views[0].State && ((FSceneViewState*)Views[0].State)->bIsFrozen;
const bool bHasViewParent = Views[0].State && ((FSceneViewState*)Views[0].State)->HasViewParent();
#endif
const bool bIsOcclusionTesting = DoOcclusionQueries() && (!bIsWireframe || bIsViewFrozen || bHasViewParent);
// Dynamic vertex and index buffers need to be committed before rendering.
FGlobalDynamicVertexBuffer::Get().Commit();
FGlobalDynamicIndexBuffer::Get().Commit();
// Notify the FX system that the scene is about to be rendered.
if (Scene->FXSystem)
{
Scene->FXSystem->PreRender();
}
// Draw the scene pre-pass / early z pass, populating the scene depth buffer and HiZ
RenderPrePass();
// Clear scene color buffer if necessary.
if ( bRequiresRHIClear )
{
ClearView();
// Only clear once.
bRequiresRHIClear = false;
}
// Clear LPVs for all views
if ( IsFeatureLevelSupported(GRHIShaderPlatform, ERHIFeatureLevel::SM5) )
{
ClearLPVs();
}
// only temporarily available after early z pass and until base pass
check(!GSceneRenderTargets.DBufferA);
check(!GSceneRenderTargets.DBufferB);
check(!GSceneRenderTargets.DBufferC);
if(IsDBufferEnabled())
{
GSceneRenderTargets.ResolveSceneDepthTexture();
// Resolve the scene depth to an auxiliary texture when SM3/SM4 is in use. This needs to happen so the auxiliary texture can be bound as a shader parameter
// while the primary scene depth texture can be bound as the target. Simultaneously binding a single DepthStencil resource as a parameter and target
// is unsupported in d3d feature level 10.
if(!(GRHIFeatureLevel >= ERHIFeatureLevel::SM5) && GRHIFeatureLevel >= ERHIFeatureLevel::SM4)
{
GSceneRenderTargets.ResolveSceneDepthToAuxiliaryTexture();
}
// e.g. ambient cubemaps, ambient occlusion, deferred decals
for(int32 ViewIndex = 0;ViewIndex < Views.Num();ViewIndex++)
{
SCOPED_CONDITIONAL_DRAW_EVENTF(EventView,Views.Num() > 1, DEC_SCENE_ITEMS, TEXT("View%d"), ViewIndex);
GCompositionLighting.ProcessBeforeBasePass(Views[ViewIndex]);
}
}
if(bIsWireframe && FDeferredShadingSceneRenderer::ShouldCompositeEditorPrimitives(Views[0]))
{
// In Editor we want wire frame view modes to be MSAA for better quality. Resolve will be done with EditorPrimitives
RHISetRenderTarget(GSceneRenderTargets.GetEditorPrimitivesColor(), GSceneRenderTargets.GetEditorPrimitivesDepth());
RHIClear(true, FLinearColor(0, 0, 0, 0), true, 0.0f, false, 0, FIntRect());
}
else
{
// Begin rendering to scene color
GSceneRenderTargets.BeginRenderingSceneColor(true);
}
RenderBasePass();
if(ViewFamily.EngineShowFlags.VisualizeLightCulling)
{
// clear out emissive and baked lighting (not too efficient but simple and only needed for this debug view)
GSceneRenderTargets.BeginRenderingSceneColor(false);
RHIClear(true, FLinearColor(0, 0, 0, 0), false, 0, false, 0, FIntRect());
}
GSceneRenderTargets.DBufferA.SafeRelease();
GSceneRenderTargets.DBufferB.SafeRelease();
GSceneRenderTargets.DBufferC.SafeRelease();
// only temporarily available after early z pass and until base pass
check(!GSceneRenderTargets.DBufferA);
check(!GSceneRenderTargets.DBufferB);
check(!GSceneRenderTargets.DBufferC);
if (bRequiresFarZQuadClear)
{
// Clears view by drawing quad at maximum Z
// TODO: if all the platforms have fast color clears, we can replace this with an RHIClear.
ClearGBufferAtMaxZ();
bRequiresFarZQuadClear = false;
}
GSceneRenderTargets.ResolveSceneColor(FResolveRect(0, 0, ViewFamily.FamilySizeX, ViewFamily.FamilySizeY));
GSceneRenderTargets.ResolveSceneDepthTexture();
// Resolve the scene depth to an auxiliary texture when SM3/SM4 is in use. This needs to happen so the auxiliary texture can be bound as a shader parameter
// while the primary scene depth texture can be bound as the target. Simultaneously binding a single DepthStencil resource as a parameter and target
// is unsupported in d3d feature level 10.
if(!GSupportsDepthFetchDuringDepthTest)
{
GSceneRenderTargets.ResolveSceneDepthToAuxiliaryTexture();
}
RenderCustomDepthPass();
// Notify the FX system that opaque primitives have been rendered and we now have a valid depth buffer.
if (Scene->FXSystem && Views.IsValidIndex(0))
{
Scene->FXSystem->PostRenderOpaque(
Views.GetTypedData(),
GSceneRenderTargets.GetSceneDepthTexture(),
GSceneRenderTargets.GetGBufferATexture()
);
}
// Update the quarter-sized depth buffer with the current contents of the scene depth texture.
// This needs to happen before occlusion tests, which makes use of the small depth buffer.
UpdateDownsampledDepthSurface();
// Issue occlusion queries
// This is done after the downsampled depth buffer is created so that it can be used for issuing queries
if ( bIsOcclusionTesting )
{
BeginOcclusionTests();
}
// Render lighting.
if (ViewFamily.EngineShowFlags.Lighting
&& GRHIFeatureLevel >= ERHIFeatureLevel::SM4
&& ViewFamily.EngineShowFlags.DeferredLighting
)
{
// Pre-lighting composition lighting stage
// e.g. deferred decals, blurred GBuffer
for(int32 ViewIndex = 0;ViewIndex < Views.Num();ViewIndex++)
{
SCOPED_CONDITIONAL_DRAW_EVENTF(EventView,Views.Num() > 1, DEC_SCENE_ITEMS, TEXT("View%d"), ViewIndex);
GCompositionLighting.ProcessAfterBasePass(Views[ViewIndex]);
}
// Clear the translucent lighting volumes before we accumulate
ClearTranslucentVolumeLighting();
RenderLights();
InjectAmbientCubemapTranslucentVolumeLighting();
CompositeIndirectTranslucentVolumeLighting();
// Filter the translucency lighting volume now that it is complete
FilterTranslucentVolumeLighting();
// Clear LPVs for all views
if ( IsFeatureLevelSupported(GRHIShaderPlatform, ERHIFeatureLevel::SM5) )
{
PropagateLPVs();
}
// Render reflections that only operate on opaque pixels
RenderDeferredReflections();
// Post-lighting composition lighting stage
// e.g. ambient cubemaps, ambient occlusion, LPV indirect
for(int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
{
SCOPED_CONDITIONAL_DRAW_EVENTF(EventView,Views.Num() > 1, DEC_SCENE_ITEMS, TEXT("View%d"), ViewIndex);
GCompositionLighting.ProcessLighting(Views[ViewIndex]);
}
}
if( ViewFamily.EngineShowFlags.StationaryLightOverlap &&
GRHIFeatureLevel >= ERHIFeatureLevel::SM4)
{
RenderStationaryLightOverlap();
}
FLightShaftsOutput LightShaftOutput;
// Draw Lightshafts
if (ViewFamily.EngineShowFlags.LightShafts)
{
LightShaftOutput = RenderLightShaftOcclusion();
}
// Draw atmosphere
if(ShouldRenderAtmosphere(ViewFamily))
{
if (Scene->AtmosphericFog)
{
// Update RenderFlag based on LightShaftTexture is valid or not
if (LightShaftOutput.bRendered)
{
Scene->AtmosphericFog->RenderFlag &= EAtmosphereRenderFlag::E_LightShaftMask;
}
else
{
Scene->AtmosphericFog->RenderFlag |= EAtmosphereRenderFlag::E_DisableLightShaft;
}
#if WITH_EDITOR
if (Scene->bIsEditorScene)
{
// Precompute Atmospheric Textures
Scene->AtmosphericFog->PrecomputeTextures(Views.GetTypedData(), &ViewFamily);
}
#endif
RenderAtmosphere(LightShaftOutput);
}
}
// Draw fog.
if(ShouldRenderFog(ViewFamily))
{
RenderFog(LightShaftOutput);
}
// No longer needed, release
LightShaftOutput.LightShaftOcclusion = NULL;
// Draw translucency.
if(ViewFamily.EngineShowFlags.Translucency)
{
SCOPE_CYCLE_COUNTER(STAT_TranslucencyDrawTime);
if(ViewFamily.EngineShowFlags.Refraction)
{
// to apply refraction effect by distorting the scene color
RenderDistortion();
}
RenderTranslucency();
}
if (ViewFamily.EngineShowFlags.LightShafts)
{
RenderLightShaftBloom();
}
// Resolve the scene color for post processing.
GSceneRenderTargets.ResolveSceneColor(FResolveRect(0, 0, ViewFamily.FamilySizeX, ViewFamily.FamilySizeY));
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
if(CVarTestUIBlur.GetValueOnRenderThread() > 0)
{
Views[0].UIBlurOverrideRectangles.Add(FIntRect(20, 20, 400, 400));
}
#endif
// Finish rendering for each view.
if(ViewFamily.bResolveScene)
{
SCOPED_DRAW_EVENT(FinishRendering, DEC_SCENE_ITEMS);
SCOPE_CYCLE_COUNTER(STAT_FinishRenderViewTargetTime);
for(int32 ViewIndex = 0;ViewIndex < Views.Num();ViewIndex++)
{
SCOPED_CONDITIONAL_DRAW_EVENTF(EventView, Views.Num() > 1, DEC_SCENE_ITEMS, TEXT("View%d"), ViewIndex);
FinishRenderViewTarget(&Views[ViewIndex], ViewIndex == (Views.Num() - 1));
}
}
RenderFinish();
}
