// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'

Shader "Hidden/ChromaticAberrationShader" {
	Properties {
		_MainTex ("Base", 2D) = "" {}
	}
	
	CGINCLUDE
	
	#include "UnityCG.cginc"
	
	struct v2f {
		float4 pos : POSITION;
		float2 uv : TEXCOORD0;
	};
	
	sampler2D _MainTex;
	
	float4 _MainTex_TexelSize;
	float _ChromaticAberration;

		
	v2f vert( appdata_img v ) {
		v2f o;
		o.pos = UnityObjectToClipPos(v.vertex);
		
		#if SHADER_API_D3D9 || SHADER_API_D3D11 || SHADER_API_XBOX360
		if (_MainTex_TexelSize.y < 0)
			 v.texcoord.y = 1.0 - v.texcoord.y ;
		#endif
		
		o.uv = v.texcoord.xy;
		return o;
	} 
	
	half4 fragSimpleCopy(v2f i) : COLOR {
		return tex2D (_MainTex, i.uv.xy);
	}

	half4 frag(v2f i) : COLOR {
		half2 coords = i.uv;
		half2 uv = i.uv;
		
		coords = (coords - 0.5) * 2.0;		
		half coordDot = dot (coords,coords);
		
		float2 uvG = uv - _MainTex_TexelSize.xy * _ChromaticAberration * coords * coordDot;
		half4 color = tex2D (_MainTex, uv);
		#if SHADER_API_D3D9
			// Work around Cg's code generation bug for D3D9 pixel shaders :(
			color.g = color.g * 0.0001 + tex2D (_MainTex, uvG).g;
		#else
			color.g = tex2D (_MainTex, uvG).g;
		#endif
		
		return color;
	}

	ENDCG 
	
Subshader {
 Pass {
	  ZTest Always Cull Off ZWrite Off
	  Fog { Mode off }      

      CGPROGRAM
      
      #pragma vertex vert
      #pragma fragment fragSimpleCopy
      
      ENDCG
  }
Pass {
	  ZTest Always Cull Off ZWrite Off
	  Fog { Mode off }      

      CGPROGRAM
      
      #pragma vertex vert
      #pragma fragment frag
      
      ENDCG
  }
}

Fallback off
	
} // shader