// Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld'
// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'

Shader "Unity Shaders Book/Common/Bumped Diffuse" {
	Properties {
		_Color ("Color Tint", Color) = (1, 1, 1, 1)
		_MainTex ("Main Tex", 2D) = "white" {}
		_BumpMap ("Normal Map", 2D) = "bump" {}
	}
	SubShader {
		Tags { "RenderType"="Opaque" "Queue"="Geometry"}

		Pass { 
			Tags { "LightMode"="ForwardBase" }
		
			CGPROGRAM
			
			#pragma multi_compile_fwdbase
			
			#pragma vertex vert
			#pragma fragment frag
			
			#include "Lighting.cginc"
			#include "AutoLight.cginc"
			
			fixed4 _Color;
			sampler2D _MainTex;
			float4 _MainTex_ST;
			sampler2D _BumpMap;
			float4 _BumpMap_ST;
			
			struct a2v {
				float4 vertex : POSITION;
				float3 normal : NORMAL;
				float4 tangent : TANGENT;
				float4 texcoord : TEXCOORD0;
			};
			
			struct v2f {
				float4 pos : SV_POSITION;
				float4 uv : TEXCOORD0;
				float4 TtoW0 : TEXCOORD1;  
				float4 TtoW1 : TEXCOORD2;  
				float4 TtoW2 : TEXCOORD3;
				SHADOW_COORDS(4)
			};
			
			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;
				
				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);  
				
				TRANSFER_SHADOW(o);
				
				return o;
			}
			
			fixed4 frag(v2f i) : SV_Target {
				float3 worldPos = float3(i.TtoW0.w, i.TtoW1.w, i.TtoW2.w);
				fixed3 lightDir = normalize(UnityWorldSpaceLightDir(worldPos));
				fixed3 viewDir = normalize(UnityWorldSpaceViewDir(worldPos));
				
				fixed3 bump = UnpackNormal(tex2D(_BumpMap, i.uv.zw));
				bump = normalize(half3(dot(i.TtoW0.xyz, bump), dot(i.TtoW1.xyz, bump), dot(i.TtoW2.xyz, bump)));
				
				fixed3 albedo = tex2D(_MainTex, i.uv.xy).rgb * _Color.rgb;
				
				fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz * albedo;
			
			 	fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(bump, lightDir));
				
				UNITY_LIGHT_ATTENUATION(atten, i, worldPos);
				
				return fixed4(ambient + diffuse * atten, 1.0);
			}
			
			ENDCG
		}
		
		Pass { 
			Tags { "LightMode"="ForwardAdd" }
			
			Blend One One
		
			CGPROGRAM
			
			#pragma multi_compile_fwdadd
			// Use the line below to add shadows for point and spot lights
//			#pragma multi_compile_fwdadd_fullshadows
			
			#pragma vertex vert
			#pragma fragment frag
			
			#include "Lighting.cginc"
			#include "AutoLight.cginc"
			
			fixed4 _Color;
			sampler2D _MainTex;
			float4 _MainTex_ST;
			sampler2D _BumpMap;
			float4 _BumpMap_ST;
			
			struct a2v {
				float4 vertex : POSITION;
				float3 normal : NORMAL;
				float4 tangent : TANGENT;
				float4 texcoord : TEXCOORD0;
			};
			
			struct v2f {
				float4 pos : SV_POSITION;
				float4 uv : TEXCOORD0;
				float4 TtoW0 : TEXCOORD1;  
				float4 TtoW1 : TEXCOORD2;  
				float4 TtoW2 : TEXCOORD3;
				SHADOW_COORDS(4)
			};
			
			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;
				
				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);  
				
				TRANSFER_SHADOW(o);
				
				return o;
			}
			
			fixed4 frag(v2f i) : SV_Target {
				float3 worldPos = float3(i.TtoW0.w, i.TtoW1.w, i.TtoW2.w);
				fixed3 lightDir = normalize(UnityWorldSpaceLightDir(worldPos));
				fixed3 viewDir = normalize(UnityWorldSpaceViewDir(worldPos));
				
				fixed3 bump = UnpackNormal(tex2D(_BumpMap, i.uv.zw));
				bump = normalize(half3(dot(i.TtoW0.xyz, bump), dot(i.TtoW1.xyz, bump), dot(i.TtoW2.xyz, bump)));
				
				fixed3 albedo = tex2D(_MainTex, i.uv.xy).rgb * _Color.rgb;
				
			 	fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(bump, lightDir));
				
				UNITY_LIGHT_ATTENUATION(atten, i, worldPos);
				
				return fixed4(diffuse * atten, 1.0);
			}
			
			ENDCG
		}
	} 
	FallBack "Diffuse"
}