// Upgrade NOTE: replaced '_World2Object' with 'unity_WorldToObject'

Shader "LXC/04 Diffuse"
{
	SubShader
	{
		Pass{
		Tags{"LightMode"="ForwardBase"}
		CGPROGRAM
#include "Lighting.cginc"
#pragma vertex vert		
#pragma fragment frag

		struct a2v {	
		float4 vertex:POSITION;	
		float3 normal:NORMAL;
		};
		
		struct v2f {
		float4 position:SV_POSITION;	
		fixed3 color : COLOR;
		};
			
		v2f vert(a2v v) {
			v2f f;
			f.position = UnityObjectToClipPos(v.vertex);
			fixed3 normalDir = normalize(mul(v.normal, (float3x3) unity_WorldToObject));	//從模型空間到世界空間
			fixed3 lightDir = normalize(_WorldSpaceLightPos0.xyz);					//第一個直射光的位置 _WorldSpaceLightPos0,對於每個頂點來說，光的位置就是光的方向
			//取得漫反射的顏色
			fixed3 diffuse = _LightColor0.rgb * max (dot(normalDir,lightDir),0);	//獲取第一個直射光的顏色 _LightColor0在#include "Lighting.cginc"裡
			f.color = diffuse;
			return f;
		}


		fixed4 frag(v2f f) :SV_Target{
		return fixed4(f.color,1);
	}
		ENDCG
	}
	}
		Fallback "VertexLit"
}