1、单张纹理
Shader "Unity Shaders Study/Day Three/SingleTexture"
{
Properties
{
_Color("Colot Tint", Color) = (1, 1, 1, 1)
//2D是纹理属性的声明方式。以一个字符串后跟一个花括号作为它的初始值，"white"是内置纹理的名字，代表一个全白纹理
_MainTex("Main Tex", 2D) = "white"{}
_Specular("Specular", Color) = (1, 1, 1, 1)
_Gloss("Gloss", Range(8.0, 256)) = 20
}
SubShader
{
Pass
{
Tags{"LightMode" = "ForwardBase"}
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "Lighting.cginc"
fixed4 _Color;
sampler2D _MainTex;
//纹理名_ST的方式来声明某个纹理的属性。 ST是缩放和平移的缩写
//_MainTex_ST.xy 缩放值 _MainTex_ST.zw 偏移值
float4 _MainTex_ST;
fixed4 _Specular;
float _Gloss;
struct a2v
{
float4 vertex : POSITION;
float3 normal : NORMAL;
float4 texcoord : TEXCOORD0;
};
struct v2f
{
float4 pos : SV_POSITION;
float3 worldNormal : TEXCOORD0;
float3 worldPos : TEXCOORD1;
float2 uv : TEXCOORD2;
};
v2f vert(a2v v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.worldNormal = UnityObjectToWorldNormal(v.normal);
o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;
//对顶点纹理坐标进行缩放，然后偏移
o.uv = TRANSFORM_TEX(v.texcoord, _MainTex);
return o;
};
fixed4 frag(v2f i) : SV_Target
{
//计算时间空间下的法线方向和光照方向
fixed3 worldNormal = normalize(i.worldNormal);
fixed3 worldLightDir = normalize(UnityWorldSpaceLightDir(i.worldPos));
//对纹理进行采样，第一个参数 需要被采样的纹理，第二个参数 float2类型的纹理坐标，返回计算得到的纹素值。将采样结果和颜色相乘作为材质的反射率
fixed3 albedo = tex2D(_MainTex, i.uv).rgb * _Color.rgb;
//和环境光照相乘得到环境光部分
fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz * albedo;
//计算漫反射光照
fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(worldNormal, worldLightDir));
//计算高光反射光照
float3 viewDir = normalize(UnityWorldSpaceViewDir(i.worldPos));
float3 halfDir = normalize(worldLightDir + viewDir);
float3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0, dot(worldNormal, halfDir)), _Gloss);
return fixed4(ambient + diffuse + specular, 1.0);
}
ENDCG
}
}
FallBack "Specular"
}
2、凹凸映射（切线空间计算）
Shader "Unity Shaders Study/Day Three/NormalMapTangentSpace"
{
Properties
{
_Color("Color Tint", Color) = (1, 1, 1, 1)
_MainTex("Main Tex", 2D) = "white"{}
//将bump作为默认值 bump是unity内置的法线纹理，当没有提供任何法线纹理时，对应了模型自带的发现信息
_BumpMap("Normal Map", 2D) = "bump"{}
//控制凹凸程度，为0时，意味着该法线纹理不会对光照产生任何影响
_BumpScale("Bump Scale", Float) = 1.0
_Specular("Specular", Color) = (1, 1, 1, 1)
_Gloss("Gloss", Range(8.0, 256)) = 20
}
SubShader
{
Pass
{
Tags{"LightMode" = "ForwardBase"}
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "Lighting.cginc"
fixed4 _Color;
sampler2D _MainTex;
float4 _MainTex_ST;
sampler2D _BumpMap;
float4 _BumpMap_ST;
float _BumpScale;
fixed4 _Specular;
float _Gloss;
struct a2v
{
float4 vertex : POSITION;
float3 normal : NORMAL;
float4 tangent : TANGENT;
float4 texcoord : TEXCOORD0;
};
struct v2f
{
float4 pos : SV_POSITION;
float4 uv : TEXCOORD0;
float3 lightDir : TEXCOORD1;
float3 viewDir : TEXCOORD2;
};
v2f vert(a2v v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.uv.xy = v.texcoord.xy * _MainTex_ST.xy + _MainTex_ST.zw;
o.uv.zw = v.texcoord.xy * _BumpMap_ST.xy + _BumpMap_ST.zw;
//计算副切线
float3 binormal = cross(normalize(v.normal), normalize(v.tangent.xyz)) * v.tangent.w;
//构造矩阵，将向量从模型空间转换到切线空间
float3x3 rotation = float3x3(v.tangent.xyz, binormal, v.normal);
o.lightDir = mul(rotation, ObjSpaceLightDir(v.vertex)).xyz;
o.viewDir = mul(rotation, ObjSpaceViewDir(v.vertex)).xyz;
return o;
}
fixed4 frag(v2f i) : SV_Target
{
fixed3 tangentLightDir = normalize(i.lightDir);
fixed3 tangentViewDir = normalize(i.viewDir);
fixed4 packedNormal = tex2D(_BumpMap, i.uv.zw);
fixed3 tangentNormal;
tangentNormal = UnpackNormal(packedNormal);
tangentNormal.xy *= _BumpScale;
tangentNormal.z = sqrt(1.0 - saturate(dot(tangentNormal.xy, tangentNormal.xy)));
fixed3 albedo = tex2D(_MainTex, i.uv).rgb * _Color.rgb;
fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz * albedo;
fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(tangentNormal, tangentLightDir));
fixed3 halfDir = normalize(tangentLightDir + tangentViewDir);
fixed3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0, dot(tangentNormal, halfDir)), _Gloss);
return fixed4(ambient + diffuse + specular, 1.0);
}
ENDCG
}
}
FallBack "Specular"
}
3、凹凸映射（在世界空间下计算光照模型）
Shader "Unity Shaders Study/Day Three/NormalMapWorldSpace"
{
Properties
{
_Color("Color Tint", Color) = (1, 1, 1, 1)
_MainTex("Main Tex", 2D) = "white"{}
//将bump作为默认值 bump是unity内置的法线纹理，当没有提供任何法线纹理时，对应了模型自带的发现信息
_BumpMap("Normal Map", 2D) = "bump"{}
//控制凹凸程度，为0时，意味着该法线纹理不会对光照产生任何影响
_BumpScale("Bump Scale", Float) = 1.0
_Specular("Specular", Color) = (1, 1, 1, 1)
_Gloss("Gloss", Range(8.0, 256)) = 20
}
SubShader
{
Pass
{
Tags{"LightMode" = "ForwardBase"}
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "Lighting.cginc"
fixed4 _Color;
sampler2D _MainTex;
float4 _MainTex_ST;
sampler2D _BumpMap;
float4 _BumpMap_ST;
float _BumpScale;
fixed4 _Specular;
float _Gloss;
struct a2v
{
float4 vertex : POSITION;
float3 normal : NORMAL;
float4 tangent : TANGENT;
float4 texcoord : TEXCOORD0;
};
struct v2f
{
float4 pos : SV_POSITION;
float4 uv : TEXCOORD0;
//一个插值寄存器最多只能存储float4大小的变量
//对于矩阵，可以按行拆成多个变量再进行存储
float4 TtoW0 : TEXCOORD1;
float4 TtoW1 : TEXCOORD2;
float4 TtoW2 : TEXCOORD3;
};
v2f vert(a2v v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.uv.xy = v.texcoord.xy * _MainTex_ST.xy + _MainTex_ST.zw;
o.uv.zw = v.texcoord.xy * _BumpMap_ST.xy + _BumpMap_ST.zw;
//将世界空间下的顶点切线、副切线和法线的矢量表示存储进切线空间到世界空间的变换矩阵
float3 worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;
fixed3 worldNormal = UnityObjectToWorldNormal(v.normal);
fixed3 worldTangent = UnityObjectToWorldDir(v.tangent.xyz);
fixed3 worldBinormal = cross(worldNormal, worldTangent) * v.tangent.w;
o.TtoW0 = float4(worldTangent.x, worldBinormal.x, worldNormal.x, worldPos.x);
o.TtoW1 = float4(worldTangent.y, worldBinormal.y, worldNormal.y, worldPos.y);
o.TtoW2 = float4(worldTangent.z, worldBinormal.z, worldNormal.z, worldPos.z);
return o;
}
fixed4 frag(v2f i) : SV_Target
{
//在世界坐标下计算光照
float3 worldPos = float3(i.TtoW0.w, i.TtoW1.w, i.TtoW2.w);
fixed3 tangentLightDir = normalize(UnityWorldSpaceLightDir(worldPos));
fixed3 tangentViewDir = normalize(UnityWorldSpaceViewDir(worldPos));
fixed4 packedNormal = tex2D(_BumpMap, i.uv.zw);
fixed3 tangentNormal;
tangentNormal = UnpackNormal(packedNormal);
tangentNormal.xy *= _BumpScale;
tangentNormal.z = sqrt(1.0 - saturate(dot(tangentNormal.xy, tangentNormal.xy)));
fixed3 albedo = tex2D(_MainTex, i.uv).rgb * _Color.rgb;
fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz * albedo;
fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(tangentNormal, tangentLightDir));
fixed3 halfDir = normalize(tangentLightDir + tangentViewDir);
fixed3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0, dot(tangentNormal, halfDir)), _Gloss);
return fixed4(ambient + diffuse + specular, 1.0);
}
ENDCG
}
}
FallBack "Specular"
}
4、渐变纹理（半兰伯特模型）
Shader "Unity Shaders Study/Day Three/RampTexture"
{
Properties
{
_Color("Color Tint", Color) = (1, 1, 1, 1)
_RampTex("Ramp Tex", 2D) = "white"{}
_Specular("Specular", Color) = (1, 1, 1, 1)
_Gloss("Gloss", Range(8.0, 256)) = 20
}
SubShader
{
Pass
{
Tags{"LightMode" = "ForwardBase"}
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "Lighting.cginc"
fixed4 _Color;
sampler2D _RampTex;
float4 _RampTex_ST;
fixed4 _Specular;
float _Gloss;
struct a2v
{
float4 vertex : POSITION;
float3 normal : NORMAL;
float4 texcoord : TEXCOORD0;
};
struct v2f
{
float4 pos : SV_POSITION;
float3 worldNormal : TEXCOORD0;
float3 worldPos : TEXCOORD1;
float2 uv : TEXCOORD2;
};
v2f vert(a2v v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.worldNormal = UnityObjectToWorldNormal(v.normal);
o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;
o.uv = TRANSFORM_TEX(v.texcoord, _RampTex);
return o;
}
fixed4 frag(v2f i) : SV_Target
{
fixed3 worldNormal = normalize(i.worldNormal);
fixed3 worldLightDir = normalize(UnityWorldSpaceLightDir(i.worldPos));
fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz;
fixed halfLambert = 0.5 * dot(worldNormal, worldLightDir) + 0.5;
fixed3 diffuseColor = tex2D(_RampTex, fixed2(halfLambert, halfLambert)).rgb * _Color.rgb;
fixed3 diffuse = _LightColor0.rgb * diffuseColor;
fixed3 viewDir = normalize(UnityWorldSpaceViewDir(i.worldPos));
fixed3 halfDir = normalize(worldLightDir + viewDir);
fixed3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0, dot(worldNormal, halfDir)), _Gloss);
return fixed4(ambient + diffuse + specular, 1.0);
}
ENDCG
}
}
FallBack "Specular"
}
