Shader "Hidden/Nature/Tree Creator Leaves Rendertex" {
Properties {
	_TranslucencyColor ("Translucency Color", Color) = (0.73,0.85,0.41,1) // (187,219,106,255)
	_Cutoff ("Alpha cutoff", Range(0,1)) = 0.5
	_HalfOverCutoff ("0.5 / alpha cutoff", Range(0,1)) = 1.0
	_TranslucencyViewDependency ("View dependency", Range(0,1)) = 0.7
	
	_MainTex ("Base (RGB) Alpha (A)", 2D) = "white" {}
	_BumpSpecMap ("Normalmap (GA) Spec (R) Shadow Offset (B)", 2D) = "bump" {}
	_TranslucencyMap ("Trans (B) Gloss(A)", 2D) = "white" {}
}

SubShader {  
	
	Pass {
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
#include "UnityBuiltin3xTreeLibrary.cginc"

struct v2f {
	float4 pos : SV_POSITION;
	float2 uv : TEXCOORD0;
	float3 color : TEXCOORD1; 
	float3 backContrib : TEXCOORD2;
	float3 nl : TEXCOORD3;
	float3 nh : TEXCOORD4;
};

CBUFFER_START(UnityTerrainImposter)
	float3 _TerrainTreeLightDirections[4];
	float4 _TerrainTreeLightColors[4];
CBUFFER_END

v2f vert (appdata_full v) {	
	v2f o;
	ExpandBillboard (UNITY_MATRIX_IT_MV, v.vertex, v.normal, v.tangent);
	o.pos = UnityObjectToClipPos(v.vertex);
	o.uv = v.texcoord.xy;
	float3 viewDir = normalize(ObjSpaceViewDir(v.vertex));
	
	for (int j = 0; j < 3; j++)
	{
		float3 lightDir = _TerrainTreeLightDirections[j];
	
		half nl = dot (v.normal, lightDir);
		
		// view dependent back contribution for translucency
		half backContrib = saturate(dot(viewDir, -lightDir));
		
		// normally translucency is more like -nl, but looks better when it's view dependent
		backContrib = lerp(saturate(-nl), backContrib, _TranslucencyViewDependency);
		o.backContrib[j] = backContrib * 2;
		
		// wrap-around diffuse
		nl = max (0, nl * 0.6 + 0.4);
		o.nl[j] = nl;
		
		half3 h = normalize (lightDir + viewDir);
		float nh = max (0, dot (v.normal, h));
		o.nh[j] = nh;
	}
	
	o.color = v.color.a;
	return o;
}

sampler2D _MainTex;
sampler2D _BumpSpecMap;
sampler2D _TranslucencyMap;
fixed _Cutoff;

half3 CalcTreeLighting(half3 lightColor, fixed3 albedo, half backContrib, half nl, half nh, half specular, half gloss)
{
	half3 translucencyColor = backContrib * _TranslucencyColor;
	
	half spec = pow (nh, specular) * gloss;
	return (albedo * (translucencyColor + nl) + _SpecColor.rgb * spec) * lightColor;
}

fixed4 frag (v2f i) : SV_Target {
	fixed4 col = tex2D (_MainTex, i.uv);
	clip (col.a - _Cutoff);
	
	fixed3 albedo = col.rgb * i.color;
	
	half specular = tex2D (_BumpSpecMap, i.uv).r * 128.0;
	
	fixed4 trngls = tex2D (_TranslucencyMap, i.uv);
	half gloss = trngls.a;
	
	half3 light = UNITY_LIGHTMODEL_AMBIENT * albedo;
	
	half3 backContribs = i.backContrib * trngls.b;
	
/*  This is unrolled below, indexing into a vec3 components is a terrible idea
	for (int j = 0; j < 3; j++)
	{
		half3 lightColor = _TerrainTreeLightColors[j].rgb;
		half3 translucencyColor = backContribs[j] * _TranslucencyColor;
		
		half nl = i.nl[j];		
		half nh = i.nh[j];
		half spec = pow (nh, specular) * gloss;
		light += (albedo * (translucencyColor + nl) + _SpecColor.rgb * spec) * lightColor;
	}*/

	light += CalcTreeLighting(_TerrainTreeLightColors[0].rgb, albedo, backContribs.x, i.nl.x, i.nh.x, specular, gloss);
	light += CalcTreeLighting(_TerrainTreeLightColors[1].rgb, albedo, backContribs.y, i.nl.y, i.nh.y, specular, gloss);
	light += CalcTreeLighting(_TerrainTreeLightColors[2].rgb, albedo, backContribs.z, i.nl.z, i.nh.z, specular, gloss);
	
	fixed4 c;
	c.rgb = light;
	c.a = 1;
	return c;
}
ENDCG
	}
}

FallBack Off
}