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Assets/measuregeneric/shaders/InteriorReflectionShader.shader

@@ -40,10 +40,30 @@ Shader "Custom/InteriorReflectionShader"
                 return o;
             }
 
+            // ChatGPT snippet
+            float3 BoxProjectReflectionDir(float3 worldPos, float3 worldRefl)
+            {
+                // Calculate relative position within the box
+                float3 boxMin = unity_SpecCube0_BoxMin;
+                float3 boxMax = unity_SpecCube0_BoxMax;
+                float3 boxCenter = 0.5 * (boxMin + boxMax);
+                float3 boxSize = boxMax - boxMin;
+
+                float3 localPos = worldPos - boxCenter;
+                float3 absLocalRefl = abs(worldRefl);
+
+                // Scale the reflection vector based on which side of the box it hits
+                float3 scale = boxSize / absLocalRefl;
+                float scaleMin = min(min(scale.x, scale.y), scale.z);
+                return localPos + worldRefl * scaleMin;
+            }
+
             fixed4 frag (v2f i) : SV_Target
             {
-                half3 worldViewDir = -normalize(UnityWorldSpaceViewDir(i.worldPos));  // Direction of ray from the camera towards the object surface
+                half3 worldViewDir = normalize(UnityWorldSpaceViewDir(i.worldPos));  // Direction of ray from the camera towards the object surface
-                half4 skyData = UNITY_SAMPLE_TEXCUBE(unity_SpecCube0, worldViewDir);
+                half3 reflection = reflect(-worldViewDir, i.worldNormal);  // Direction of ray after hitting the surface of object
+                reflection = BoxProjectReflectionDir(i.worldPos, reflection);
+                half4 skyData = UNITY_SAMPLE_TEXCUBE(unity_SpecCube0, reflection);
                 half3 skyColor = DecodeHDR(skyData, unity_SpecCube0_HDR);  // This is done becasue the cubemap is stored HDR
                 return half4(skyColor, 1.0);
             }