Shader "Math/BiasShader"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
    }
    SubShader
    {
        // No culling or depth
        Cull Off ZWrite Off ZTest Always

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma target 5.0

            #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 = mul(UNITY_MATRIX_MVP, v.vertex);
                o.uv = v.uv;
                return o;
            }

            sampler2D _MainTex;
            float4 _MainTex_TexelSize;

            float toFloat(float4 color)
            {
                int red = color.r * 255.0;
                int green = color.g * 255.0;
                int blue = color.b * 255.0;
                int alpha = color.a * 255.0;
                int intVal = (red << 0) | (green << 8) | (blue << 16) | (alpha << 24);
                return asfloat(intVal)  ;
            }
            float4 toColor(float value)
            {
                int intVal = asint(value);
                int red = (intVal >> 0) & 0xff;
                int green = (intVal >> 8) & 0xff;
                int blue = (intVal >> 16) & 0xff;
                int alpha = (intVal >> 24) & 0xff;
                return float4(red / 255.0, green / 255.0, blue / 255.0, alpha / 255.0);
            }

            float4 frag(v2f i) : SV_Target
            {
                    return tex2D(_MainTex, i.uv);
                float2 pixelUV = i.uv*_MainTex_TexelSize.zw;
                if (pixelUV.x < _MainTex_TexelSize.z - 1)
                {
                    return tex2D(_MainTex, i.uv);
                }
                else
                {
                    return toColor(1.0);
                }
            }
            ENDCG
        }
    }
}