Kastell/Assets/Shaders/Blur.shader

Shader "Geri/Blur"
{
    Properties
    {
        _Radius("Radius", Range(0, 4)) = 1
        [HideInInspector] _MainTex ("Sprite Texture", 2D) = "white" {}
    }

    Category
    {
        Tags
        {
            "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Opaque"
        }

        SubShader
        {
            GrabPass
            {
                Tags
                {
                    "LightMode" = "Always"
                }
            }

            Pass
            {
                Tags
                {
                    "LightMode" = "Always"
                }

                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                #pragma fragmentoption ARB_precision_hint_fastest
                #include "Blur.cginc"

                sampler2D _GrabTexture;
                float4 _GrabTexture_TexelSize;
                float _Radius;
                int _Enabled;

                half4 first_pass(v2f i) {
                    half4 sum = half4(0, 0, 0, 0);

                    sum += GRABXYPIXEL(0.0, 0.0);
                    int measurments = 1;

                    for (float range = 1.f; range <= _Radius * 2; range += 1.f)
                    {
                        sum += GRABXYPIXEL(range, range);
                        sum += GRABXYPIXEL(-range, range);
                        sum += GRABXYPIXEL(range, 0);
                        sum += GRABXYPIXEL(0, range);
                        measurments += 4;
                    }

                    half4 color = sum / measurments;
                    i.color.a *= _Radius / 4.0;
                    color = i.color * i.color.a + color * (1 - i.color.a);

                    return color;
                }

                half4 frag(v2f i) : COLOR
                {
                    return first_pass(i);
                }
                ENDCG
            }
        }
    }
}