Shader 学习笔记(11) RenderType为Transparent的混合透明

透明度混合可以实现真正的透明,本例中采用的混合方式为Blend SrcAlpha OneMinusSrcAlpha.Blend命令后接着写入不同的混合方式.混合方式有多种组合(后续单独写一篇).SrcAlpha OneMinusSrcAlpha的混合后效果的公式为

Shader "wx/AlphaBlendMat"{
	Properties{
		_Color("Main Tint",Color)=(1,1,1,1)
		_MainTex("Main Tex",2D)="white"{}
		_AlphaScale("Alpha Scale",Range(0,1))=1
	}
	SubShader{
		Tags{"Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent"}
		Pass{
			Tags{"LightMode"="ForwardBase"}
			ZWrite Off    //关闭深度写入
			Blend SrcAlpha OneMinusSrcAlpha
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#include "Lighting.cginc"
			fixed4 _Color;
			sampler2D _MainTex;
			float4 _MainTex_ST;
			fixed _AlphaScale;
			struct a2v
			{
				float4 vertex:POSITION;
				float3 normal:NORMAL;
				float4 texcoord:TEXCOORD0;
			};
			struct v2f
			{
				float4 pos:SV_POSITION;
				float3 worldNormal:TEXCOORD0;
				float4 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);
				o.uv=TRANSFORM_TEX(v.texcoord,_MainTex);
				return o;
			}
			fixed4 frag(v2f i):SV_Target{
				fixed3 worldNormal=normalize(i.worldNormal);
				fixed3 worldLightDir=normalize(UnityWorldSpaceLightDir(i.worldPos));
				fixed4 texColor=tex2D(_MainTex,i.uv);
				fixed3 albedo=texColor.rgb*_Color.rgb;
				fixed3 ambient=UNITY_LIGHTMODEL_AMBIENT.xyz*albedo;
				fixed3 diffuse=_LightColor0.rgb*albedo*max(0,dot(worldNormal,worldLightDir));
					return fixed4(ambient+diffuse,texColor.a*_AlphaScale);
			}
			ENDCG
		}
	}
	FallBack"VertexLit"
}