From 59643b2fb9dd5564f7406d57116e2574f945defa Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Thu, 6 Nov 2025 21:01:02 +0100
Subject: [PATCH] Add improved local-light shadow raytracing by starting ray
 from light, not surface

---
 Source/Shaders/GI/GlobalSurfaceAtlas.shader | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Source/Shaders/GI/GlobalSurfaceAtlas.shader b/Source/Shaders/GI/GlobalSurfaceAtlas.shader
index 2efa638f0..387620c5c 100644
--- a/Source/Shaders/GI/GlobalSurfaceAtlas.shader
+++ b/Source/Shaders/GI/GlobalSurfaceAtlas.shader
@@ -165,11 +165,19 @@ float4 PS_Lighting(AtlasVertexOutput input) : SV_Target
 		BRANCH
 		if (NoL > 0)
 		{
+#if RADIAL_LIGHT
+			// Shot a ray from light to the texel to see if there is any occluder
+			GlobalSDFTrace trace;
+			trace.Init(Light.Position, -L, bias, toLightDst);
+			GlobalSDFHit hit = RayTraceGlobalSDF(GlobalSDF, GlobalSDFTex, GlobalSDFMip, trace, 1.0f);
+			shadowMask = hit.IsHit() && hit.HitTime < toLightDst - bias * 3 ? LightShadowsStrength : 1;
+#else
 			// Shot a ray from texel into the light to see if there is any occluder
 			GlobalSDFTrace trace;
 			trace.Init(gBuffer.WorldPos + gBuffer.Normal * shadowBias, L, bias, toLightDst - bias);
 			GlobalSDFHit hit = RayTraceGlobalSDF(GlobalSDF, GlobalSDFTex, GlobalSDFMip, trace, 2.0f);
 			shadowMask = hit.IsHit() ? LightShadowsStrength : 1;
+#endif
 		}
 		else
 		{