Keep lens dirt aspect ratio

Author: Chman

PostProcessing/Runtime/Effects/Bloom.cs

@@ -145,12 +145,32 @@ public override void Render(PostProcessRenderContext context)
                 iterations
             );
 
+            // Lens dirtiness
+            // Keep the aspect ratio correct & center the dirt texture, we don't want it to be
+            // stretched or squashed
             var dirtTexture = settings.lensTexture.value == null
                 ? RuntimeUtilities.blackTexture
                 : settings.lensTexture.value;
 
+            var dirtRatio = (float)dirtTexture.width / (float)dirtTexture.height;
+            var screenRatio = (float)context.width / (float)context.height;
+            var dirtTileOffset = new Vector4(1f, 1f, 0f, 0f);
+
+            if (dirtRatio > screenRatio)
+            {
+                dirtTileOffset.x = screenRatio / dirtRatio;
+                dirtTileOffset.z = (1f - dirtTileOffset.x) * 0.5f;
+            }
+            else if (screenRatio > dirtRatio)
+            {
+                dirtTileOffset.y = dirtRatio / screenRatio;
+                dirtTileOffset.w = (1f - dirtTileOffset.y) * 0.5f;
+            }
+
+            // Shader properties
             var uberSheet = context.uberSheet;
             uberSheet.EnableKeyword("BLOOM");
+            uberSheet.properties.SetVector(ShaderIDs.Bloom_DirtTileOffset, dirtTileOffset);
             uberSheet.properties.SetVector(ShaderIDs.Bloom_Settings, shaderSettings);
             uberSheet.properties.SetColor(ShaderIDs.Bloom_Color, settings.color.value.linear);
             uberSheet.properties.SetTexture(ShaderIDs.Bloom_DirtTex, dirtTexture);

PostProcessing/Runtime/Utils/ShaderIDs.cs

@@ -60,6 +60,7 @@ static class ShaderIDs
         internal static readonly int Bloom_Settings                  = Shader.PropertyToID("_Bloom_Settings");
         internal static readonly int Bloom_Color                     = Shader.PropertyToID("_Bloom_Color");
         internal static readonly int Bloom_Threshold                 = Shader.PropertyToID("_Bloom_Threshold");
+        internal static readonly int Bloom_DirtTileOffset            = Shader.PropertyToID("_Bloom_DirtTileOffset");
 
         internal static readonly int ChromaticAberration_Amount      = Shader.PropertyToID("_ChromaticAberration_Amount");
         internal static readonly int ChromaticAberration_SpectralLut = Shader.PropertyToID("_ChromaticAberration_SpectralLut");

PostProcessing/Shaders/Builtins/Uber.shader

@@ -29,7 +29,8 @@ Shader "Hidden/PostProcessing/Uber"
         TEXTURE2D_SAMPLER2D(_BloomTex, sampler_BloomTex);
         TEXTURE2D_SAMPLER2D(_Bloom_DirtTex, sampler_Bloom_DirtTex);
         float4 _BloomTex_TexelSize;
-        half3 _Bloom_Settings; // x: sampleScale, y: intensity, z: lens intensity
+        float4 _Bloom_DirtTileOffset; // xy: tiling, zw: offset
+        half3 _Bloom_Settings; // x: sampleScale, y: intensity, z: lens dirt intensity
         half3 _Bloom_Color;
 
         // Chromatic aberration
@@ -142,7 +143,7 @@ Shader "Hidden/PostProcessing/Uber"
             #if BLOOM
             {
                 half4 bloom = UpsampleTent(TEXTURE2D_PARAM(_BloomTex, sampler_BloomTex), uvSPR, _BloomTex_TexelSize.xy, _Bloom_Settings.x);
-                half4 dirt = half4(SAMPLE_TEXTURE2D(_Bloom_DirtTex, sampler_Bloom_DirtTex, i.texcoord).rgb, 0.0);
+                half4 dirt = half4(SAMPLE_TEXTURE2D(_Bloom_DirtTex, sampler_Bloom_DirtTex, i.texcoord * _Bloom_DirtTileOffset.xy + _Bloom_DirtTileOffset.zw).rgb, 0.0);
 
                 // Additive bloom (artist friendly)
                 bloom *= _Bloom_Settings.y;