Help to get texture displaying in PostProcessing shader

Graphics Shaders & Materials
1

I am trying to create an Uber-Fog post-processing effect. I can’t get the fog’s 2D texture to display in the shader yet my RECT’s (main, depth texture, blur) are perfectly fine.

Am I missing something??

Shader "UberFogComposite" 
{
	Properties 
	{
		_MainTex ("Orig (RGB)", RECT) = "white" {}
		_BlurTex ("Blur (RGB)", RECT) = "white" {}
		_DepthTex ("Depth (RGB)", RECT) = "white" {}
		_FogTex ("Fog (RGBA)", 2D) = "white" {}
	}
	SubShader 
	{
		Tags { "RenderType"="Opaque" }
		Pass 
		{
			ZTest Always Cull Off ZWrite Off
			Fog { Mode off }
			Lighting Off
					
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#pragma fragmentoption ARB_precision_hint_fastest 
			#include "UnityCG.cginc"

			uniform sampler2D _FogTex;
			uniform samplerRECT _MainTex;
			uniform samplerRECT _BlurTex;
			uniform samplerRECT _DepthTex;

			struct vIn
			{
				float4 vertex : POSITION;
				float4 texcoord : TEXCOORD0;
			};
			struct vOut
			{
				float4 pos : POSITION;
				float2 uv : TEXCOORD0;
				float2 fogUv : TEXCOORD1;
			};

			vOut vert( vIn v )
			{
				vOut o;
				o.pos = mul (glstate.matrix.mvp, v.vertex);
				o.uv = MultiplyUV( glstate.matrix.texture[0], v.texcoord );
				o.fogUv = TRANSFORM_UV(0); 
				//o.fogUv.x += _Time[3];
				return o;
			}

			half4 frag (vOut i) : COLOR
			{
				half4 original = texRECT(_MainTex, i.uv);
				half4 blur = texRECT(_BlurTex, i.uv);
				half4 depth = texRECT(_DepthTex, i.uv);
				half4 fog = tex2D(_FogTex, i.fogUv);
				depth = depth * 2.0;
				depth = clamp(depth, 0, 1);
				return fog;
				//return lerp(original, blur, depth);
				
			}
			ENDCG
		}
	}
Fallback off
}

Bits from the C# side

TOP of CLASS : public Texture2D fogTexture;  
   >>> Texture is set in inspector <<< 

OnRenderImage : compositeMaterial.SetTexture ("_FogTex", fogTexture);
2

I managed to solve it. For some reason, just re-arranging the texRECT and tex2D calls made it work. The tex2D will not work after 3 texRECT calls.

Shader "UberFogComposite"
{
   Properties
   {
      _MainTex ("Orig (RGB)", RECT) = "white" {}
      _BlurTex ("Blur (RGB)", RECT) = "white" {}
      _DepthTex ("Depth (RGB)", RECT) = "white" {}
      _FogTex ("Fog (RGBA)", 2D) = "white" {}
   }
   SubShader
   {
      Tags { "RenderType"="Opaque" }
      Pass
      {
         ZTest Always Cull Off ZWrite Off
         Fog { Mode off }
         Lighting Off
               
         CGPROGRAM
         #pragma vertex vert
         #pragma fragment frag
         #pragma fragmentoption ARB_precision_hint_fastest
         #include "UnityCG.cginc"

         uniform sampler2D _FogTex;
         uniform samplerRECT _MainTex;
         uniform samplerRECT _BlurTex;
         uniform samplerRECT _DepthTex;

         struct vIn
         {
            float4 vertex : POSITION;
            float4 texcoord : TEXCOORD0;
         };
         struct vOut
         {
            float4 pos : POSITION;
            float2 uv : TEXCOORD0;
            float2 fogUv : TEXCOORD1;
         };

         vOut vert( vIn v )
         {
            vOut o;
            o.pos = mul (glstate.matrix.mvp, v.vertex);
            o.uv = MultiplyUV( glstate.matrix.texture[0], v.texcoord );
            o.fogUv = TRANSFORM_UV(0);
            //o.fogUv.x += _Time[3];
            return o;
         }

         half4 frag (vOut i) : COLOR
         {
            half4 original = texRECT(_MainTex, i.uv);
            half4 fog = tex2D(_FogTex, i.fogUv);
half4 blur = texRECT(_BlurTex, i.uv);
            half4 depth = texRECT(_DepthTex, i.uv);
            
            depth = depth * 2.0;
            depth = clamp(depth, 0, 1);
            return fog;
            //return lerp(original, blur, depth);
            
         }
         ENDCG
      }
   }
Fallback off
}