// Curved World <http://u3d.as/1W8h>
// Copyright (c) Amazing Assets <https://amazingassets.world>
 
// Per pixel bumped refraction.
// Uses a normal map to distort the image behind, and
// an additional texture to tint the color.

Shader "Amazing Assets/Curved World/Unity Standard Assets/Glass/Stained BumpDistort" 
{
	Properties 
	{
		[HideInInspector][CurvedWorldBendSettings] _CurvedWorldBendSettings("0|1|1", Vector) = (0, 0, 0, 0)

		_BumpAmt  ("Distortion", range (0,128)) = 10
		_Color ("Tint Color", color) = (1, 1, 1, 1)
		_MainTex ("Map", 2D) = "white" {}
		_BumpMap ("Normalmap", 2D) = "bump" {}
	}

	Category 
	{

		// We must be transparent, so other objects are drawn before this one.
		Tags { "Queue"="Transparent" "RenderType"="Opaque" }


		SubShader 
		{

			// This pass grabs the screen behind the object into a texture.
			// We can access the result in the next pass as _GrabTexture
			GrabPass 
			{
				Name "BASE"
				Tags { "LightMode" = "Always" }
			}
		
			// Main pass: Take the texture grabbed above and use the bumpmap to perturb it
			// on to the screen
			Pass 
			{
				Name "BASE"
				Tags { "LightMode" = "Always" }
			
				CGPROGRAM
				#pragma vertex vert
				#pragma fragment frag
				#pragma multi_compile_fog
				#include "UnityCG.cginc"


#define CURVEDWORLD_BEND_TYPE_CLASSICRUNNER_X_POSITIVE
#define CURVEDWORLD_BEND_ID_1
#pragma shader_feature_local CURVEDWORLD_DISABLED_ON
#pragma shader_feature_local CURVEDWORLD_NORMAL_TRANSFORMATION_ON
#include "Assets/Amazing Assets/Curved World/Shaders/Core/CurvedWorldTransform.cginc"


				struct appdata_t 
				{
					float4 vertex : POSITION;
					float3 normal : NORMAL;
					float4 tangent : TANGENT;
					float2 texcoord: TEXCOORD0;
				};

				struct v2f 
				{
					float4 vertex : SV_POSITION;
					float4 uvgrab : TEXCOORD0;
					float2 uvbump : TEXCOORD1;
					float2 uvmain : TEXCOORD2;
					UNITY_FOG_COORDS(3)
				};

				fixed4 _Color;
				float _BumpAmt;
				float4 _BumpMap_ST;
				float4 _MainTex_ST;

				v2f vert (appdata_t v)
				{
					v2f o;

#if defined(CURVEDWORLD_IS_INSTALLED) && !defined(CURVEDWORLD_DISABLED_ON)
   #ifdef CURVEDWORLD_NORMAL_TRANSFORMATION_ON
      CURVEDWORLD_TRANSFORM_VERTEX_AND_NORMAL(v.vertex, v.normal, v.tangent)
   #else
      CURVEDWORLD_TRANSFORM_VERTEX(v.vertex)
   #endif
#endif

					o.vertex = UnityObjectToClipPos(v.vertex);
					o.uvgrab = ComputeGrabScreenPos(o.vertex);
					o.uvbump = TRANSFORM_TEX( v.texcoord, _BumpMap );
					o.uvmain = TRANSFORM_TEX( v.texcoord, _MainTex );
					UNITY_TRANSFER_FOG(o,o.vertex);
					return o;
				}

				sampler2D _GrabTexture;
				float4 _GrabTexture_TexelSize;
				sampler2D _BumpMap;
				sampler2D _MainTex;

				half4 frag (v2f i) : SV_Target
				{
					#if UNITY_SINGLE_PASS_STEREO
					i.uvgrab.xy = TransformStereoScreenSpaceTex(i.uvgrab.xy, i.uvgrab.w);
					#endif

					// calculate perturbed coordinates
					half2 bump = UnpackNormal(tex2D( _BumpMap, i.uvbump )).rg; // we could optimize this by just reading the x & y without reconstructing the Z
					float2 offset = bump * _BumpAmt * _GrabTexture_TexelSize.xy;
					#ifdef UNITY_Z_0_FAR_FROM_CLIPSPACE //to handle recent standard asset package on older version of unity (before 5.5)
						i.uvgrab.xy = offset * UNITY_Z_0_FAR_FROM_CLIPSPACE(i.uvgrab.z) + i.uvgrab.xy;
					#else
						i.uvgrab.xy = offset * i.uvgrab.z + i.uvgrab.xy;
					#endif

					half4 col = tex2Dproj( _GrabTexture, UNITY_PROJ_COORD(i.uvgrab));
					half4 tint = tex2D(_MainTex, i.uvmain) * _Color;
					col *= tint;
					UNITY_APPLY_FOG(i.fogCoord, col);
					return col;
				}
				ENDCG
			}
		}
	}

	CustomEditor "AmazingAssets.CurvedWorld.Editor.DefaultShaderGUI"
}