Reduce DDGI probes distance limit to improve performance

Source/Engine/Renderer/GI/DynamicDiffuseGlobalIllumination.cpp

@@ -46,7 +46,8 @@ PACK_STRUCT(struct Data0
     GlobalSignDistanceFieldPass::ConstantsData GlobalSDF;
     GlobalSurfaceAtlasPass::ConstantsData GlobalSurfaceAtlas;
     GBufferData GBuffer;
-    Float2 Padding0;
+    float Padding0;
+    float ProbesDistanceLimit;
     float ResetBlend;
     float TemporalTime;
     Int4 ProbeScrollClears[4];
@@ -471,6 +472,7 @@ bool DynamicDiffuseGlobalIlluminationPass::RenderInner(RenderContext& renderCont
         data.DDGI = ddgiData.Result.Constants;
         data.GlobalSDF = bindingDataSDF.Constants;
         data.GlobalSurfaceAtlas = bindingDataSurfaceAtlas.Constants;
+        data.ProbesDistanceLimit = 1.05f; // TODO: expose to be configurable?
         data.ResetBlend = clear ? 1.0f : 0.0f;
         for (int32 cascadeIndex = 0; cascadeIndex < cascadesCount; cascadeIndex++)
         {

Source/Shaders/GI/DDGI.shader

@@ -27,7 +27,8 @@ DDGIData DDGI;
 GlobalSDFData GlobalSDF;
 GlobalSurfaceAtlasData GlobalSurfaceAtlas;
 GBufferData GBuffer;
-float2 Padding0;
+float Padding0;
+float ProbesDistanceLimit;
 float ResetBlend;
 float TemporalTime;
 int4 ProbeScrollClears[4];
@@ -111,7 +112,7 @@ void CS_Classify(uint3 DispatchThreadId : SV_DispatchThreadID)
 #endif
     float sdfDst = abs(sdf);
     float threshold = GlobalSDF.CascadeVoxelSize[CascadeIndex];
-    float distanceLimit = length(probesSpacing) * 1.5f;
+    float distanceLimit = length(probesSpacing) * ProbesDistanceLimit;
     float relocateLimit = length(probesSpacing) * 0.6f;
     if (sdfDst > distanceLimit) // Probe is too far from geometry
     {