手写unity shader实现光晕（外发光）
// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)' // Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld' // Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld' // Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)' Shader "Shader Learn/OutLighting" //Shader文件索引路径 { // 属性 Properties { _MainTex("Texture(RGB)", 2D) = "grey" {} //表面贴图 默认灰色 _Color("Color", Color) = (0, 0, 0, 1) //为贴图附加的颜色 默认为白色 _AtmoColor("Atmosphere Color", Color) = (0, 0.4, 1.0, 1) //光晕颜色 _Size("Size", Float) = 0.1 //光晕范围 _OutLightPow("Falloff",Float) = 5 //光晕平方参数 _OutLightStrength("Transparency", Float) = 15 //光晕强度 } SubShader { Pass //通道1 用于给物体贴图、填色 { Name "PlaneBase" Tags{ "LightMode" = "Always" } Cull Back //CG程序开始 CGPROGRAM //声明顶点着色器函数为vert #pragma vertex vert //声明片段着色器函数为frag #pragma fragment frag #include "UnityCG.cginc" //函数可能用到的参数 uniform sampler2D _MainTex; uniform float4 _MainTex_ST; uniform float4 _Color; uniform float4 _AtmoColor; uniform float _Size; uniform float _OutLightPow; uniform float _OutLightStrength; //顶点着色器的输出 struct vertexOutput { float4 pos:SV_POSITION; float3 normal:TEXCOORD0; float3 worldvertpos:TEXCOORD1; float2 texcoord:TEXCOORD2; }; //顶点着色器函数 vertexOutput vert(appdata_base v) { vertexOutput o; // 顶点位置 o.pos = UnityObjectToClipPos(v.vertex); // 法线 o.normal = v.normal; // 世界坐标顶点位置 o.worldvertpos = mul(unity_ObjectToWorld, v.vertex).xyz; // 纹理 o.texcoord = TRANSFORM_TEX(v.texcoord, _MainTex); return o; } //片段着色器函数 float4 frag(vertexOutput i) :COLOR { float4 color = tex2D(_MainTex, i.texcoord); //i.normal = normalize(i.normal); 视角法线 //float3 viewdir = normalize(i.worldvertpos.xyz - _worldspacecamerapos.xyz);// normalize(i.worldvertpos - _worldspacecamerepos); //float4 color0 = _atmocolor; 视角法线与模型法线点积形成中间指为1向四周逐渐衰减为0的点积值，赋给透明通道，形成光晕效果 //color0.a = _outlightpow*(1 - dot(viewdir, i.normal)); //color.rgb = lerp(color.rgb, color0.rgb, color0.a); // 纹理贴图叠加颜色 return color*_Color; } ENDCG } //通道2： 用于生成模型外部的光晕 Pass { Name "AtmosphereBase" Tags{ "LightMode" = "Always" } Cull Front Blend SrcAlpha One CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" uniform float4 _Color; uniform float4 _AtmoColor; uniform float _Size; uniform float _OutLightPow; uniform float _OutLightStrength; struct vertexOutput { float4 pos:SV_POSITION; float3 normal:TEXCOORD0; float3 worldvertpos:TEXCOORD1; }; vertexOutput vert(appdata_base v) { vertexOutput o; //顶点位置以法线方向向外延伸 v.vertex.xyz += v.normal*_Size; o.pos = UnityObjectToClipPos(v.vertex); o.normal = v.normal; o.worldvertpos = mul(unity_ObjectToWorld, v.vertex); return o; } float4 frag(vertexOutput i):COLOR { i.normal = normalize(i.normal); //视角法线 float3 viewdir = normalize(i.worldvertpos.xyz - _WorldSpaceCameraPos.xyz);// normalize(i.worldvertpos - _WorldSpaceCamerePos); float4 color = _AtmoColor; //视角法线与模型法线点积形成中间指为1向四周逐渐衰减为0的点积值，赋给透明通道，形成光晕效果 color.a = pow(saturate(dot(viewdir, i.normal)), _OutLightPow); color.a *= _OutLightStrength*dot(viewdir, i.normal); return color; } ENDCG } } FallBack "Diffuse" }
