我们可以看到很多游戏经常会有这种模型边缘发光的效果，看起来很高大上的样子。其实实现起来挺简单的，网上也有很多这样的例子分享，现在我也来分享一下两种Shader实现的代码吧。
1.Surface Shader
Shader "Custom/Rim Light" { Properties { _MainTex("Base (RGB)", 2D) = "white" {} _RimColor("_RimColor", Color) =(0.17,0.36,0.81,0.0) _RimWidth("_RimWidth", Range(0.6,9.0)) = 0.9 } SubShader { Tags{ "RenderType" = "Opaque"} LOD 150 CGPROGRAM #pragma surface surf Lambert struct Input { float2 uv_MainTex; float3 viewDir; }; sampler2D _MainTex; fixed4 _RimColor; fixed _RimWidth; void surf (Input IN, inout SurfaceOutput o) { fixed4 t = tex2D (_MainTex, IN.uv_MainTex); o.Albedo = t.rgb; o.Alpha = t.a; half rim = 1.0 - saturate(dot (normalize(IN.viewDir), o.Normal)); o.Emission= _RimColor.rgb * pow (rim, _RimWidth); } ENDCG } Fallback "Diffuse" }主要是这两句起到关键作用。
half rim = 1.0 - saturate(dot (normalize(IN.viewDir), o.Normal)); o.Emission= _RimColor.rgb * pow (rim, _RimWidth);如果不想受灯光影响，可以在Tags加上"LightMode"="Always"
2.Vetex and Fragment Shader
Shader "Custom/Rim Light VF" { Properties { _MainTex ("Base (RGB)", 2D) = "white" {} _Color ("Main Color", Color) = (1,1,1,1) _RimColor ("Rim Color", Color) = (1, 1, 1, 1) _RimWidth ("Rim Width", float) = 0.9 } SubShader { Pass { Lighting Off CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" struct appdata { float4 vertex : POSITION; float3 normal : NORMAL; float2 texcoord : TEXCOORD0; }; struct v2f { float4 pos : SV_POSITION; float2 uv : TEXCOORD0; fixed3 color : COLOR; }; uniform float4 _MainTex_ST; uniform fixed4 _RimColor; float _RimWidth; v2f vert (appdata_base v) { v2f o; o.pos = mul (UNITY_MATRIX_MVP, v.vertex); float3 viewDir = normalize(ObjSpaceViewDir(v.vertex)); float dotProduct = 1 - dot(v.normal, viewDir); o.color = smoothstep(1 - _RimWidth, 1.0, dotProduct); o.color *= _RimColor; o.uv = v.texcoord.xy; return o; } uniform sampler2D _MainTex; uniform fixed4 _Color; fixed4 frag(v2f i) : COLOR { fixed4 texcol = tex2D(_MainTex, i.uv); texcol *= _Color; texcol.rgb += i.color; return texcol; } ENDCG } } } 当然最关键的还是vert方法里的代码，具体两种方法大家可以根据需求使用。看看效果，赶紧试试吧。
