integrated PCA palette to render pipeline

Assets/Resources/Shaders/PCAWater.shader

@@ -0,0 +1,62 @@
+Shader "Compute/PCAWater"
+{
+    Properties
+    {
+        _MainTex ("Source", 2D) = "white" {}
+        _LowTex  ("Low", 2D) = "white" {}
+        _HighTex ("High", 2D) = "white" {}
+        _MaskTex ("Mask", 2D) = "white" {}
+    }
+    SubShader
+    {
+        Pass
+        {
+            name "Default"
+        CGPROGRAM
+            #include "UnityCG.cginc"
+            #include "UnityUI.cginc"
+
+            #pragma vertex vert
+            #pragma fragment frag
+
+            sampler2D _MainTex;
+            sampler2D _LowTex;
+            sampler2D _HighTex;
+            sampler2D _MaskTex;
+
+            struct appdata_t
+            {
+                float4 vertex   : POSITION;
+                float2 texcoord : TEXCOORD0;
+            };
+
+            struct v2f
+            {
+                float4 vertex   : SV_POSITION;
+                float2 texcoord : TEXCOORD0;
+            };
+
+            v2f vert(appdata_t v)
+            {
+                v2f OUT;
+
+                OUT.vertex = UnityObjectToClipPos(v.vertex);
+                OUT.texcoord = v.texcoord;
+
+                return OUT;
+            }
+
+            half4 frag(v2f IN) : SV_Target
+            {
+                float a = tex2D(_MaskTex, IN.texcoord).r;
+                clip(a - 0.01);
+
+                half4 color = lerp(tex2D(_LowTex, IN.texcoord), tex2D(_HighTex, IN.texcoord), tex2D(_MainTex, IN.texcoord).r);
+                color.a = a;
+
+                return color;
+            }
+        ENDCG
+        }
+    }
+}

Assets/Resources/Shaders/UIMask.shader

@@ -78,7 +78,11 @@ Shader "UI/Mask"
             half4 frag(v2f IN) : SV_Target
             {
                 half4 color = _Color;
-                color.a *= tex2D(_MainTex, IN.texcoord).r;
+                float v = tex2D(_MainTex, IN.texcoord).r;
+
+                clip(v - 0.01);
+
+                color.a *= v;
 
                 return color;
             }