Added ChannelMixer

Editor/AssetsHelpers/Implementation/Texture/ChannelMixer/ChannelMixer.shader

@@ -0,0 +1,61 @@
+Shader "Hidden/ChannelMixer"
+{
+    Properties
+    {
+        _MainTex ("Red Channel Texture", 2D) = "white"
+    }
+    SubShader
+    {
+        Cull Off 
+        ZWrite Off 
+        ZTest Always
+
+        Pass
+        {
+            CGPROGRAM
+
+            #pragma vertex vert
+            #pragma fragment frag
+
+            #pragma shader_feature_local _HAS_TEX_R
+            #pragma shader_feature_local _HAS_TEX_G
+            #pragma shader_feature_local _HAS_TEX_B
+            #pragma shader_feature_local _HAS_TEX_A
+
+            #include "UnityCG.cginc"
+
+            struct appdata {
+                float4 vertex : POSITION;
+                float2 uv : TEXCOORD0;
+            };
+
+            struct v2f {
+                float2 uv : TEXCOORD0;
+                float4 vertex : SV_POSITION;
+            };
+
+            v2f vert(appdata v) {
+                v2f o;
+                o.vertex = UnityObjectToClipPos(v.vertex);
+                o.uv = v.uv;
+                return o;
+            }
+
+            sampler2D _MainTex;
+            int4 _ChannelSource;
+
+            float4 frag (v2f i) : SV_Target
+            {
+                float4 color = tex2D(_MainTex, i.uv);
+
+                float r = color[_ChannelSource.x];
+                float g = color[_ChannelSource.y];
+                float b = color[_ChannelSource.z];
+                float a = color[_ChannelSource.w];
+
+                return float4(r, g, b, a);
+            }
+            ENDCG
+        }
+    }
+}