From c93b0a00ba6ea6cc8a0b4685fb5de6c11e5aa4ad Mon Sep 17 00:00:00 2001
From: raccoon <raccoon@home.net>
Date: Thu, 7 Nov 2024 21:25:07 +0500
Subject: [PATCH] Better solution

---
 .../shaders/InteriorReflectionShader.shader   | 50 +++++--------------
 1 file changed, 13 insertions(+), 37 deletions(-)

diff --git a/Assets/measuregeneric/shaders/InteriorReflectionShader.shader b/Assets/measuregeneric/shaders/InteriorReflectionShader.shader
index 490ff85..c1b7487 100644
--- a/Assets/measuregeneric/shaders/InteriorReflectionShader.shader
+++ b/Assets/measuregeneric/shaders/InteriorReflectionShader.shader
@@ -1,15 +1,14 @@
+// Original code from https://gist.github.com/josephbk117/a43f5335cea9b3e12a44f196dc81f30f
 Shader "Custom/InteriorReflectionShader"
 {
     Properties
     {
-        _ReflectionIntensity ("Reflection Intensity", Range(0, 1)) = 1.0
+        // TODO: Implement me!
+        _Opacity("Opacity", Range(0.0, 1.0)) = 1.0
     }
-    
+
     SubShader
     {
-        Tags { "RenderType"="Opaque" }
-        LOD 300
-
         Pass
         {
             CGPROGRAM
@@ -17,10 +16,7 @@ Shader "Custom/InteriorReflectionShader"
             #pragma fragment frag
             #include "UnityCG.cginc"
 
-            float _ReflectionIntensity;
-
-            // Use built-in cubemap sampler (unity_SpecCube0) for reflection probe
-            // UNITY_DECLARE_TEXCUBE(unity_SpecCube0);
+            float _Opacity;  // TODO: Implement me!
 
             struct appdata
             {
@@ -28,11 +24,11 @@ Shader "Custom/InteriorReflectionShader"
                 float3 normal : NORMAL;
             };
 
-            struct v2f
+            struct v2f 
             {
-                float4 pos : SV_POSITION;
                 float3 worldPos : TEXCOORD0;
                 float3 worldNormal : TEXCOORD1;
+                float4 pos : SV_POSITION;
             };
 
             v2f vert (appdata v)
@@ -40,38 +36,18 @@ Shader "Custom/InteriorReflectionShader"
                 v2f o;
                 o.pos = UnityObjectToClipPos(v.vertex);
                 o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;
-                o.worldNormal = normalize(mul((float3x3)unity_ObjectToWorld, v.normal));
+                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                 return o;
             }
 
-            half3 ComputeBoxProjectedReflection(float3 worldPos, float3 worldNormal)
+            fixed4 frag (v2f i) : SV_Target
             {
-                // Calculate direction from the object to the reflection probe position
-                float3 probeToPixel = worldPos - unity_SpecCube0_ProbePosition;
-
-                // Calculate inverse box scale manually
-                float3 boxSize = unity_SpecCube0_BoxMax - unity_SpecCube0_BoxMin;
-                float3 invBoxSize = 1.0 / boxSize;
-
-                // Transform the position into the box projection space
-                float3 localPos = probeToPixel * invBoxSize + 0.5;
-
-                // Calculate reflection direction
-                float3 reflectionDir = normalize(worldPos - _WorldSpaceCameraPos);
-
-                // Sample the cubemap using the adjusted reflection direction
-                return UNITY_SAMPLE_TEXCUBE(unity_SpecCube0, reflectionDir).rgb;
-            }
-
-            half4 frag (v2f i) : SV_Target
-            {
-                // Calculate reflection using box projection
-                half3 reflectionColor = ComputeBoxProjectedReflection(i.worldPos, i.worldNormal);
-                return half4(reflectionColor, 1.0);
+                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 skyColor = DecodeHDR(skyData, unity_SpecCube0_HDR);  // This is done becasue the cubemap is stored HDR
+                return half4(skyColor, 1.0);
             }
             ENDCG
         }
     }
-    
-    FallBack "Diffuse"
 }