unity shader 凹凸纹理

有经常看到用unityshader来模仿物体表面的凹凸纹理。

具体的shader代码如下：

Shader "Aotushader" {

Properties {

_Color ("Color Tint", Color) = (1, 1, 1, 1)

_MainTex ("Main Tex", 2D) = "white" {}

_BumpMap ("Normal Map", 2D) = "bump" {}

_BumpScale ("Bump Scale", Float) = 1.0     //法线贴图

_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 = mul(UNITY_MATRIX_MVP, 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;

fixed3 worldNormal = UnityObjectToWorldNormal(v.normal);

fixed3 worldTangent = UnityObjectToWorldDir(v.tangent.xyz); 

fixed3 worldBinormal = cross(worldNormal, worldTangent) * v.tangent.w;

float4x4 tangentToWorld = float4x4(worldTangent.x, worldBinormal.x, worldNormal.x, 0.0,

  worldTangent.y, worldBinormal.y, worldNormal.y, 0.0,

  worldTangent.z, worldBinormal.z, worldNormal.z, 0.0,

  0.0, 0.0, 0.0, 1.0);

float3x3 worldToTangent = inverse(tangentToWorld);

// Transform the light and view dir from world space to tangent space

o.lightDir = mul(worldToTangent, WorldSpaceLightDir(v.vertex));

o.viewDir = mul(worldToTangent, WorldSpaceViewDir(v.vertex));

return o;

}

fixed4 frag(v2f i) : SV_Target {

fixed3 tangentLightDir = normalize(i.lightDir);

fixed3 tangentViewDir = normalize(i.viewDir);

// Get the texel in the normal map

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"

｝

最终效果：