Shader "Unlit/AlphaPremultiplied"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		yFlip ("display name", Int) = 0
	}
	SubShader
	{
		Tags { "RenderType"="Opeque" }
		LOD 100
		Blend One Zero
		//Blend One OneMinusSrcAlpha
		
		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			// make fog work
			#pragma multi_compile_fog
			
			#include "UnityCG.cginc"

			struct appdata
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				UNITY_FOG_COORDS(1)
				float4 vertex : SV_POSITION;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			int yFlip;
			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				UNITY_TRANSFER_FOG(o,o.vertex);
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
				// sample the texture
				float2 uv = i.uv;
				if (yFlip == 1)
					uv = i.uv*float2(1.0, -1.0) + float2(0.0, 1.0);
				fixed4 col = tex2D(_MainTex, uv);
				col.rgb *= col.a;
				return col;
			}
			ENDCG
		}
	}
}