VerticalScroll.shader

Shader "Hidden/VerticalScroll"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
    }

    CGINCLUDE
    #include "UnityCG.cginc"

    sampler2D _MainTex;
    float _ScrollValue;

    fixed4 frag (v2f_img i) : SV_Target
    {
        float u = i.uv.x;
        float v = i.uv.y;
        // 小数点部分だけをオフセットする
        // fracは小数点だけを残す関数
        v = frac(v + _ScrollValue);
        return tex2D(_MainTex, float2(u, v));
    }
    ENDCG
    SubShader
    {
        Pass
        {
            CGPROGRAM
            #pragma vertex vert_img
            #pragma fragment frag
            ENDCG
        }
    }
}