矢量精灵的颜色着色器

Question

Unity 2020.2.7 Vector Graphics 2.0.0 预览版 14

我的着色器是这样工作的：如果颜色 alpha 是 255 - 我可以给任何颜色着色。 如果颜色 alpha 为 0 - 原始颜色。 如果 .svg 生成的资产类型是纹理精灵，则效果很好。 但是如果我切换到生成的资产类型 - 矢量精灵，我的着色器不起作用。如何解决？ 谢谢

Shader "Custom/TintSprite"{ Properties
{
    [PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
    _Color("Tint", Color) = (1,1,1,1)
    [MaterialToggle] PixelSnap("Pixel snap", Float) = 0
}

    SubShader
    {
        Tags
        {
            "Queue" = "Transparent"
            "IgnoreProjector" = "True"
            "RenderType" = "Transparent"
            "PreviewType" = "Plane"
            "CanUseSpriteAtlas" = "True"
        }

        Cull Off
        Lighting Off
        ZWrite Off
        Fog { Mode Off }
        Blend One OneMinusSrcAlpha

        Pass
        {
        CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma multi_compile DUMMY PIXELSNAP_ON
            #pragma multi_compile_instancing
            #include "UnityCG.cginc"

            struct appdata_t
            {
                float4 vertex   : POSITION;
                float4 color    : COLOR;
                float2 texcoord : TEXCOORD0;
            };

            struct v2f
            {
                float4 vertex   : SV_POSITION;
                fixed4 color : COLOR;
                half2 texcoord  : TEXCOORD0;
            };

            fixed4 _Color;

            v2f vert(appdata_t IN)
            {
                v2f OUT;
                OUT.vertex = UnityObjectToClipPos(IN.vertex);
                OUT.texcoord = IN.texcoord;
                OUT.color = IN.color * _Color;
                #ifdef PIXELSNAP_ON
                OUT.vertex = UnityPixelSnap(OUT.vertex);
                #endif

                return OUT;
            }

            sampler2D _MainTex;

            fixed4 frag(v2f IN) : SV_Target
            {
                fixed4 c = tex2D(_MainTex, IN.texcoord);
                fixed a = c.a;
                if (c.a >= 0.1) {
                    c = c + (IN.color - c) * IN.color.a;
                    c.a = a;
                }
                c.rgb *= c.a;
                return c;
            }
        ENDCG
        }
    }}

https://i.stack.imgur.com/H5W6J.png

https://i.stack.imgur.com/S1wpm.png

https://i.stack.imgur.com/0coZ9.png