Sprites/Diffuse with Hue shift

Unity Engine
1

Hi guys, i worked on a sprite shader which can accept lights like the sprites/diffuse but including hue shift too.
This is because i searched a lot for such a shader but never found exactly this specific effect. Its a very simple shader so you can extend it as you want.

Shader "Sprites/DefaultSprite" {
    Properties{
        _MainTex("Texture", 2D) = "white" {}
        _HueShift("HueShift", Float) = 0
    }
        SubShader{
        Tags{ "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" }
        ZWrite Off
        Blend SrcAlpha OneMinusSrcAlpha
        Cull Off
        CGPROGRAM

        //#pragma surface surf Lambert
#pragma surface surf Lambert alpha
#pragma target 3.0

    float3 rgb_to_hsv_no_clip(float3 RGB)
    {
        float3 HSV;

        float minChannel, maxChannel;
        if (RGB.x > RGB.y) {
            maxChannel = RGB.x;
            minChannel = RGB.y;
        }
        else {
            maxChannel = RGB.y;
            minChannel = RGB.x;
        }

        if (RGB.z > maxChannel) maxChannel = RGB.z;
        if (RGB.z < minChannel) minChannel = RGB.z;

        HSV.xy = 0;
        HSV.z = maxChannel;
        float delta = maxChannel - minChannel;             //Delta RGB value
        if (delta != 0)
        {                    // If gray, leave H  S at zero
            HSV.y = delta / HSV.z;
            float3 delRGB;
            delRGB = (HSV.zzz - RGB + 3 * delta) / (6.0*delta);
            if (RGB.x == HSV.z) HSV.x = delRGB.z - delRGB.y;
            else if (RGB.y == HSV.z) HSV.x = (1.0 / 3.0) + delRGB.x - delRGB.z;
            else if (RGB.z == HSV.z) HSV.x = (2.0 / 3.0) + delRGB.y - delRGB.x;
        }
        return (HSV);
    }

    float3 hsv_to_rgb(float3 HSV)
    {
        float3 RGB = HSV.z;

        float var_h = HSV.x * 6;
        float var_i = floor(var_h);   // Or ... var_i = floor( var_h )
        float var_1 = HSV.z * (1.0 - HSV.y);
        float var_2 = HSV.z * (1.0 - HSV.y * (var_h - var_i));
        float var_3 = HSV.z * (1.0 - HSV.y * (1 - (var_h - var_i)));
        if (var_i == 0) { RGB = float3(HSV.z, var_3, var_1); }
        else if (var_i == 1) { RGB = float3(var_2, HSV.z, var_1); }
        else if (var_i == 2) { RGB = float3(var_1, HSV.z, var_3); }
        else if (var_i == 3) { RGB = float3(var_1, var_2, HSV.z); }
        else if (var_i == 4) { RGB = float3(var_3, var_1, HSV.z); }
        else { RGB = float3(HSV.z, var_1, var_2); }

        return (RGB);
    }

    struct Input {
        float2 uv_MainTex;
    };

    sampler2D _MainTex;
    float _HueShift;

    void surf(Input IN, inout SurfaceOutput o) {
        o.Albedo = tex2D(_MainTex, IN.uv_MainTex).rgb;

        float3 hsv = rgb_to_hsv_no_clip(o.Albedo.xyz);
        hsv.x += _HueShift;
     
        o.Albedo = half3(hsv_to_rgb(hsv));
        o.Alpha = tex2D(_MainTex, IN.uv_MainTex).a;
    }

    ENDCG
    }
        Fallback "Diffuse"
}
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2

FYI, this blog has optimized version which remove if-else statement RGB to HSV/HSL/HCY/HCL in HLSL - chilliant.com

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