Shader "Unlit/WorldShader"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		_Bounds("Bounds", Vector) = (0,0,0,0)
	}
	SubShader
	{
		Tags { "RenderType"="Transparent"  "Queue"="Transparent" "IgnoreProjector"="True" }
		LOD 100

		ZWrite Off
		Blend SrcAlpha OneMinusSrcAlpha

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			// make fog work
			#pragma multi_compile_fog
			
			#include "UnityCG.cginc"
			#include "AutoLight.cginc"

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

			struct v2f
			{
				float2 uv : TEXCOORD0;
				UNITY_FOG_COORDS(1)
				float4 vertex : SV_POSITION;
				float2 screenPos : TEXCOORD1;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;

			float4 _Bounds;

			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				UNITY_TRANSFER_FOG(o,o.vertex);
				o.screenPos = ComputeScreenPos(o.vertex);
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
				// sample the texture
				//fixed4 col = tex2D(_MainTex, (i.screenPos.xy - _Bounds.xy) / _Bounds.zw);
				//fixed4 col = half4(half2((i.screenPos.xy - _Bounds.xy) / _Bounds.zw), 0, 1);
				fixed4 col = tex2D(_MainTex, (i.screenPos.xy - _Bounds.xy) / _Bounds.zw);
				//float xVal = (i.screenPos.x - _Bounds.x) / _Bounds.z;
				//float xVal = i.screenPos.x;
				//fixed4 col = half4(half3(xVal, xVal, xVal), 1);
				// apply fog
				//UNITY_APPLY_FOG(i.fogCoord, col);
				return col;
			}
			ENDCG
		}
	}
}