Unity3d《Shader篇》法线贴图

效果图

 

贴图

 

法线贴图

 

//代码

Shader "Custom/NormalMap" {
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		_NormalMap ("NormalMap", 2D) = "bump" {}
		_Color ("Main Color", Color) = (1,1,1,1)
		_SpecColor("Specular Color", Color) = (0.5,0.5,0.5,1)
		_Shininess("Shininess", Range(0.01,1)) = 0.1
	}
	
 	
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 300
		
		
			CGPROGRAM

			
			#pragma surface surf PPL
			
			sampler2D _MainTex;
			sampler2D _NormalMap;
			float4 _Color;
			//float4 _SpecColor;
			float _Shininess;
			
			struct Input
			{
				float2 uv_MainTex;
			};
			
			// Forward lighting
		half4 LightingPPL (SurfaceOutput s, half3 lightDir, half3 viewDir, half atten)
		{
			half3 nNormal = normalize(s.Normal);
			half shininess = s.Gloss * 250.0 + 4.0;

		#ifndef USING_DIRECTIONAL_LIGHT
			lightDir = normalize(lightDir);
		#endif

			// Phong shading model
			//half reflectiveFactor = max(0.0, dot(-viewDir, reflect(lightDir, nNormal)));

			// Blinn-Phong shading model
			half reflectiveFactor = max(0.0, dot(nNormal, normalize(lightDir + viewDir)));

			half diffuseFactor = max(0.0, dot(nNormal, lightDir));
			half specularFactor = pow(reflectiveFactor, shininess) * s.Specular;

			half4 c;
			c.rgb = (s.Albedo * diffuseFactor + _SpecColor.rgb * specularFactor) * _LightColor0.rgb;
			c.rgb *= (atten * 2.0);
			c.a = s.Alpha;
			return c;
		}
		
			void surf(Input IN, inout SurfaceOutput o)
			{
				half4 tex 	= tex2D(_MainTex, IN.uv_MainTex) * _Color;
				o.Albedo 	= tex.rgb;
				o.Alpha 	= _Color.a;
				o.Normal	= UnpackNormal(tex2D(_NormalMap, IN.uv_MainTex));
				o.Specular 	= tex.a;
				o.Gloss 	= _Shininess;
			}
			
			ENDCG
		
	}
	
	Fallback "Diffuse"
}