shader知识：http://imgtec.eetrend.com/blogs/%E5%A2%A8%E5%8D%8A%E6%88%90%E9%9C%9C
最终效果
Shader "Learning Unity Shader/Lecture 14/Basic Rim Shader"
{
//-----------------------------------【属性 || Properties】------------------------------------------
Properties
{
//主颜色 || Main Color
_MainColor("【主颜色】Main Color", Color) = (0.5,0.5,0.5,1)
//漫反射纹理 || Diffuse Texture
_TextureDiffuse("【漫反射纹理】Texture Diffuse", 2D) = "white" {}
//边缘发光颜色 || Rim Color
_RimColor("【边缘发光颜色】Rim Color", Color) = (0.5,0.5,0.5,1)
//边缘发光强度 ||Rim Power
_RimPower("【边缘发光强度】Rim Power", Range(0.0, 36)) = 0.1
//边缘发光强度系数 || Rim Intensity Factor
_RimIntensity("【边缘发光强度系数】Rim Intensity", Range(0.0, 100)) = 3
}
//----------------------------------【子着色器 || SubShader】---------------------------------------
SubShader
{
//渲染类型为Opaque，不透明 || RenderType Opaque
Tags
{
"RenderType" = "Opaque"
}
//---------------------------------------【唯一的通道 || Pass】------------------------------------
Pass
{
//设定通道名称 || Set Pass Name
Name "ForwardBase"
//设置光照模式 || LightMode ForwardBase
Tags
{
"LightMode" = "ForwardBase"
}
//-------------------------开启CG着色器编程语言段 || Begin CG Programming Part----------------------
CGPROGRAM
//【1】指定顶点和片段着色函数名称 || Set the name of vertex and fragment shader function
#pragma vertex vert
#pragma fragment frag
//【2】头文件包含 || include
#include "UnityCG.cginc"
#include "AutoLight.cginc"
//【3】指定Shader Model 3.0 || Set Shader Model 3.0
#pragma target 3.0
//【4】变量声明 || Variable Declaration
//系统光照颜色
uniform float4 _LightColor0;
//主颜色
uniform float4 _MainColor;
//漫反射纹理
uniform sampler2D _TextureDiffuse;
//漫反射纹理_ST后缀版
uniform float4 _TextureDiffuse_ST;
//边缘光颜色
uniform float4 _RimColor;
//边缘光强度
uniform float _RimPower;
//边缘光强度系数
uniform float _RimIntensity;
//【5】顶点输入结构体 || Vertex Input Struct
struct VertexInput
{
//顶点位置 || Vertex position
float4 vertex : POSITION;
//法线向量坐标 || Normal vector coordinates
float3 normal : NORMAL;
//一级纹理坐标 || Primary texture coordinates
float4 texcoord : TEXCOORD0;
};
//【6】顶点输出结构体 || Vertex Output Struct
struct VertexOutput
{
//像素位置 || Pixel position
float4 pos : SV_POSITION;
//一级纹理坐标 || Primary texture coordinates
float4 texcoord : TEXCOORD0;
//法线向量坐标 || Normal vector coordinates
float3 normal : NORMAL;
//世界空间中的坐标位置 || Coordinate position in world space
float4 posWorld : TEXCOORD1;
//创建光源坐标,用于内置的光照 || Function in AutoLight.cginc to create light coordinates
LIGHTING_COORDS(3,4)
};
//【7】顶点着色函数 || Vertex Shader Function
VertexOutput vert(VertexInput v)
{
//【1】声明一个顶点输出结构对象 || Declares a vertex output structure object
VertexOutput o;
//【2】填充此输出结构 || Fill the output structure
//将输入纹理坐标赋值给输出纹理坐标
o.texcoord = v.texcoord;
//获取顶点在世界空间中的法线向量坐标
o.normal = mul(float4(v.normal,0), _World2Object).xyz;
//获得顶点在世界空间中的位置坐标
o.posWorld = mul(_Object2World, v.vertex);
//获取像素位置
o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
//【3】返回此输出结构对象 || Returns the output structure
return o;
}
//【8】片段着色函数 || Fragment Shader Function
fixed4 frag(VertexOutput i) : COLOR
{
//【8.1】方向参数准备 || Direction
//视角方向
float3 ViewDirection = normalize(_WorldSpaceCameraPos.xyz - i.posWorld.xyz);
//法线方向
float3 Normalection = normalize(i.normal);
//光照方向
float3 LightDirection = normalize(_WorldSpaceLightPos0.xyz);
//【8.2】计算光照的衰减 || Lighting attenuation
//衰减值
float Attenuation = LIGHT_ATTENUATION(i);
//衰减后颜色值
float3 AttenColor = Attenuation * _LightColor0.xyz;
//【8.3】计算漫反射 || Diffuse
float NdotL = dot(Normalection, LightDirection);
float3 Diffuse = max(0.0, NdotL) * AttenColor + UNITY_LIGHTMODEL_AMBIENT.xyz;
//【8.4】准备自发光参数 || Emissive
//计算边缘强度
half Rim = 1.0 - max(0, dot(i.normal, ViewDirection));
//计算出边缘自发光强度
float3 Emissive = _RimColor.rgb * pow(Rim,_RimPower) *_RimIntensity;
//【8.5】计在最终颜色中加入自发光颜色 || Calculate the final color
//最终颜色 = （漫反射系数 x 纹理颜色 x rgb颜色）+自发光颜色 || Final Color=(Diffuse x Texture x rgbColor)+Emissive
float3 finalColor = Diffuse * (tex2D(_TextureDiffuse,TRANSFORM_TEX(i.texcoord.rg, _TextureDiffuse)).rgb*_MainColor.rgb) + Emissive;
//【8.6】返回最终颜色 || Return final color
return fixed4(finalColor,1);
}
//-------------------结束CG着色器编程语言段 || End CG Programming Part------------------
ENDCG
}
}
//后备着色器为普通漫反射 || Fallback use Diffuse
FallBack "Diffuse"
}
