Unity3D教程：Outline Shader 实现外轮廓效果

发表于2017-03-20

这次写了一个简单利用Outline Shader 实现外轮廓效果，这个效果在游戏中常常应用在：选取物件、卡通风格中，如果对Outline Shader 实现外轮廓效果感兴趣的话，可以继续往下看。

Shader "Unlit/Outline Shader"
{
    Properties
    {
        _MainTex ("Base (RGB)", 2D) = "white" { }
        _OutlineColor ("Outline Color", Color) = (0, 0, 0, 1)
        _OutlineWidth ("Outline width", Range (0.0, 1.0)) = .005
    }
      
    SubShader
    {
        Pass
        {
            Cull front
              
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
              
            #include "UnityCG.cginc"
              
            struct appdata 
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
            };
              
            struct v2f
            {
                float4 pos : POSITION;
            };
              
            uniform float _OutlineWidth;
            uniform float4 _OutlineColor;
              
            v2f vert(appdata v)
            {
                v2f o;
                  
                float3 norm = normalize(v.normal);
                v.vertex.xyz += v.normal * _OutlineWidth;
                o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
                  
                return o;
            }
              
            half4 frag(v2f i) : COLOR
            {
                return _OutlineColor;
            }
            ENDCG
        }
          
        Pass
        {
            SetTexture [_MainTex]
            {
                Combine Primary * Texture
            }
        }
    }
}