Shader "Unlit/IsoShader"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		_CenterPoint ("Object Center", Vector) = (0,0,0,0)
		_TextureOffset("Texture Offset", Vector) = (0,0,0,0)
		_TextureScale("Texture Scale", Float) = 1
	}
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 100

		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;
				float4 screenPos : TEXCOORD1;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			float4 _MainTex_TexelSize;

			float4 _CenterPoint;
			float4 _TextureOffset;
			float _TextureScale;
			
			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				o.screenPos = ComputeScreenPos(o.vertex)
				UNITY_TRANSFER_FOG(o,o.vertex);
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
				// sample the texture
				fixed4 col = tex2D(_MainTex, (i.screenPos.xy - _CenterPoint.xy - _TextureOffset.xy * _MainTex_TexelSize.xy) / _TextureScale);

				// apply fog
				//UNITY_APPLY_FOG(i.fogCoord, col);

				return col;
			}
			ENDCG
		}
	}
}