Shader "Custom/OutlineOnly"
{
    Properties
    {
        _ClipTexture ("Clip", 2D) = "white" {}
        _OutlineCol ("Outline Color", Color) = (0,0,0,1)
        _OutlineFactor ("Outline Factor", Range(0.0, 1.0)) = 1.05
        _Progress("Thick Progress", Range(0,1)) = 0
        _ProgressA("Alpha Progress", Range(0,1)) = 0
    }
    SubShader
    {
        Tags { "Queue" = "Transparent" "RenderType" = "Opaque" }
       
        Pass  
        {  
            Cull Front
              
            CGPROGRAM  
            #pragma vertex vert  
            #pragma fragment frag  
            #include "UnityCG.cginc"  
            fixed4 _OutlineCol;  
            float _OutlineFactor;  
            float _Progress;
            float _ProgressA;
            sampler2D _ClipTexture;
            struct v2f  
            {  
                float4 pos : SV_POSITION;  
                float2 uv : TEXCOORD0;
            };  
              
            v2f vert(appdata_full v)  
            {  
                v2f o;  
              
              fixed3 outlinePos = v.vertex.xyz * ((_OutlineFactor * _Progress) + 1.0);
              o.pos = UnityObjectToClipPos(outlinePos);
              o.uv = v.texcoord;
              
              return o;
            }

            fixed4 frag(v2f i) : SV_Target
            {
                // 用模型UV采样clip贴图
                clip(tex2D(_ClipTexture, i.uv).r - (_ProgressA*1.2));
                return _OutlineCol;
            }

            ENDCG  
        }
       
    }
}