// Upgrade NOTE: replaced '_World2Object' with 'unity_WorldToObject'

// Upgrade NOTE: replaced '_Object2World' with 'unity_ObjectToWorld'

Shader "PPP/BendWorld2"
{
    Properties
    {
		_Color ("Main Color", Color) = (1,1,1,1)
		_MainTex ("Base (RGB)", 2D) = "white" {}
	}
		SubShader
	{
		Tags { "RenderType" = "Opaque" }
		LOD 200

		CGPROGRAM
		#pragma surface surf Lambert vertex:vert //addshadow

			//Global properities to be set by BendControllerRadial
			uniform half3 _CurveOrigin;
			uniform fixed3 _ReferenceDirection;
			uniform half _Curvature;
			uniform fixed3 _Scale;
			uniform half _FlatMargin;
			uniform half _HorizonWaveFrequency;


			sampler2D _MainTex;
			fixed4 _Color;

			//uniform float _Curvature;

			struct Input
			{
				float2 uv_MainTex;
			};

			half4 Bend(half4 v)
			{
				half4 wpos = mul(unity_ObjectToWorld, v);

				half2 xzDist = (wpos.xz - _CurveOrigin.xz) / _Scale.xz;
				half dist = length(xzDist);

				half2 direction = lerp(_ReferenceDirection.xz, xzDist, min(dist, 1));

				half theta = acos(clamp(dot(normalize(direction), _ReferenceDirection), -1, 1));

				dist = max(0, dist - _FlatMargin);

				wpos.y -= dist * dist * _Curvature * cos(theta * _HorizonWaveFrequency);

				wpos = mul(unity_WorldToObject, wpos);

				return wpos;

			}
			void vert(inout appdata_full v)
			{
				/*float4 worldSpace = mul(unity_ObjectToWorld, v.vertex);
				worldSpace.xyz -= _WorldSpaceCameraPos.xyz;
				worldSpace = float4(0.0f, (worldSpace.x * worldSpace.x) * -_Curvature, 0.0f, 0.0f);

				v.vertex  = mul(unity_WorldToObject, worldSpace);*/

				half4 vpos = Bend(v.vertex);

				v.vertex = vpos;
			}


			void surf(Input IN, inout SurfaceOutput o)
			{
				fixed4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
				o.Albedo = c.rgb;
				o.Alpha = c.a;
			}

			ENDCG
    }
			Fallback "Mobile/Diffuse"
}