//======= Copyright (c) Stereolabs Corporation, All rights reserved. ===============
 // Computes lighting and shadows and apply them to the real
	Shader "ZED/ZED Forward Lighting"
{

	Properties{
		[MaterialToggle] directionalLightEffect("Directional light affects image", Int) = 0
		_MaxDepth("Max Depth Range", Range(1,40)) = 40
		_DepthXYZTex("Depth texture", 2D) = "" {}
		_MainTex("Main texture", 2D) = "" {}
	}
		SubShader
		{
			ZWrite On
			Pass
			{
				Name "FORWARD"
				Tags{ "LightMode" = "Always" }

				Cull Off
				CGPROGRAM

				#define ZEDStandard
						// compile directives
				#pragma target 4.0

				#pragma vertex vert_surf
				#pragma fragment frag_surf


				#pragma multi_compile_fwdbase
				#pragma multi_compile_fwdadd_fullshadows

				#pragma multi_compile __ NO_DEPTH

				#include "HLSLSupport.cginc"
				#include "UnityShaderVariables.cginc"

				#define UNITY_PASS_FORWARDBASE
				#include "UnityCG.cginc"

				#include "AutoLight.cginc"
				#include "../ZED_Utils.cginc"
				#define ZED_SPOT_LIGHT_DECLARATION
				#define ZED_POINT_LIGHT_DECLARATION
				#include "ZED_Lighting.cginc"


				sampler2D _MainTex;

				struct Input {
					float2 uv_MainTex;
				};

				float4x4 _CameraMatrix;
				sampler2D _DirectionalShadowMap;


				struct v2f_surf {
					float4 pos : SV_POSITION;
					float4 pack0 : TEXCOORD0;
					SHADOW_COORDS(4)
						ZED_WORLD_DIR(1)

				};



				float4 _MainTex_ST;
				sampler2D _DepthXYZTex;
				float4 _DepthXYZTex_ST;
				sampler2D _MaskTex;
				int _HasShadows;
				float4 ZED_directionalLight[2];
				int directionalLightEffect;
				float _ZEDFactorAffectReal;
				float _MaxDepth;

				bool Unity_IsNan_float3(float3 In)
				{
					bool Out = (In < 0.0 || In > 0.0 || In == 0.0) ? 0 : 1;
					return Out;
				}

				// vertex shader
				v2f_surf vert_surf(appdata_full v)
				{

					v2f_surf o;
					UNITY_INITIALIZE_OUTPUT(v2f_surf,o);
					o.pos = UnityObjectToClipPos(v.vertex);

					ZED_TRANSFER_WORLD_DIR(o)

						o.pack0.xy = TRANSFORM_TEX(v.texcoord, _MainTex);
					o.pack0.zw = TRANSFORM_TEX(v.texcoord, _DepthXYZTex);

					o.pack0.y = 1 - o.pack0.y;
					o.pack0.w = 1 - o.pack0.w;

					TRANSFER_SHADOW(o);

					return o;
				}

				// fragment shader
				void frag_surf(v2f_surf IN, out fixed4 outColor : SV_Target, out float outDepth : SV_Depth)
				{
					UNITY_INITIALIZE_OUTPUT(fixed4,outColor);
					float4 uv = IN.pack0;

					float3 zed_xyz = tex2D(_DepthXYZTex, uv.zw).xxx;

					//Filter out depth values beyond the max value.
					if (_MaxDepth < 40.0) //Avoid clipping out FAR values when not using feature.
					{
						if (zed_xyz.z > _MaxDepth || Unity_IsNan_float3(zed_xyz.z)) discard;
					}

				#ifdef NO_DEPTH
					#if SHADER_API_D3D11
						outDepth = 0;
					#elif SHADER_API_GLCORE
						outDepth = 1000;//fake infinite depth
					#endif
				#else
					outDepth = computeDepthXYZ(zed_xyz.z);
				#endif
					fixed4 c = 0;
					float4 color = tex2D(_MainTex, uv.xy).bgra;
					float3 normals = tex2D(_NormalsTex, uv.zw).rgb;


					//Apply directional light
					color *=  _ZEDFactorAffectReal;

					//Compute world space
					float3 worldspace;
					GET_XYZ(IN, zed_xyz.x, worldspace)

					//Apply shadows
					// e(1) == 2.71828182846
					if (_HasShadows == 1) {
						//Depends on the ambient lighting
						float atten = saturate(tex2D(_DirectionalShadowMap, fixed2(uv.z, 1 - uv.w)) + log(1 + 1.72*length(UNITY_LIGHTMODEL_AMBIENT.rgb)/4.0));

						c = half4(color*atten);
					}
					else {
						c = half4(color);
					}


					//Add light
					c += saturate(computeLighting(color.rgb, normals, worldspace, 1));


					c.a = 0;
					outColor.rgb = c;

				}

	ENDCG

			}
		}
		Fallback Off
}