type Vector3Data
	X#
	Y#
	Z#
endtype

function Shadow_Init(Width#,Height#,Near#,Far#,Distance#)
	global Shadow_ObjectID as integer[]
	global Shadow_ShadowShaderID
	global Shadow_DepthRenderImageID
	global Shadow_DepthSpriteID
	global Shadow_DepthShaderID
	global Shadow_CameraWidth#
	global Shadow_CameraHeight#
	global Shadow_CameraNear#
	global Shadow_CameraFar#
	global Shadow_CameraNearWidth#
	global Shadow_CameraNearHeight#
	global Shadow_CameraFarWidth#
	global Shadow_CameraFarHeight#
	global Shadow_EyeVectorID
	global Shadow_AtVectorID
	global Shadow_SunVectorID
	global Shadow_MinX#
	global Shadow_MinY#
	global Shadow_MinZ#
	global Shadow_MaxX#
	global Shadow_MaxY#
	global Shadow_MaxZ#
	global Shadow_Distance#

	Shadow_EyeVectorID=CreateVector3()
	Shadow_AtVectorID=CreateVector3()
	Shadow_SunVectorID=CreateVector3(-1,-1,-1)

	Shadow_DepthShaderID=LoadShader("Depth.vs","Depth.ps")
	Shadow_DepthRenderImageID=CreateRenderImage(2048,2048,1,0)
	SetImageMinFilter(Shadow_DepthRenderImageID,1)
	SetImageMagFilter(Shadow_DepthRenderImageID,1)
	SetImageWrapU(Shadow_DepthRenderImageID,0)
	SetImageWrapV(Shadow_DepthRenderImageID,0)
	
	Shadow_ShadowShaderID=LoadShader("Object.vs","Object.ps")
	
	Shadow_CameraWidth#=Width#
	Shadow_CameraHeight#=Height#
	Shadow_CameraNear#=Near#
	Shadow_CameraFar#=Far#
	Shadow_Distance#=Distance#
	
	DeviceWidth#=GetDeviceWidth()
	DeviceHeight#=GetDeviceHeight()
	AspectRatio#=DeviceWidth#/DeviceHeight#

	SetCameraRange(1,Shadow_CameraNear#,Shadow_CameraFar#)
endfunction

function Shadow_AddObject(ObjectID)
	SetObjectImage(ObjectID,Shadow_DepthRenderImageID,1)
	SetObjectShader(ObjectID,Shadow_ShadowShaderID)
	SetObjectScreenCulling(ObjectID,0)
	Shadow_ObjectID.insert(ObjectID)
endfunction

function Shadow_RemoveObject(ObjectID)
	SetObjectShader(ObjectID,0)
	SetObjectScreenCulling(ObjectID,0)
	
	ID=Shadow_FindObjectID(ObjectID)
	Shadow_ObjectID.remove(ID)
endfunction

function Shadow_FindObjectID(ObjectID)
	repeat
		ID=ID+1
	until Shadow_ObjectID[ID]=ObjectID
endfunction ID

/*
function Shadow_SetSunPosition(PosX#,PosY#,PosZ#,DirX#,DirY#,DirZ#)
	AtVectorID=CreateVector3(PosX#+DirX#,PosY#+DirY#,PosZ#+DirZ#)
	EyeVectorID=CreateVector3(PosX#,PosY#,PosZ#)
	ViewMatrixID=BuildLookAtLhMatrix4(AtVectorID,EyeVectorID)
	DeleteVector3(AtVectorID)
	DeleteVector3(EyeVectorID)
	
	ProjectionMatrixID=creatematrix4()
	OrthographicProjectionMatrix4(ProjectionMatrixID,Shadow_CameraWidth#,Shadow_CameraHeight#,Shadow_CameraNear#,Shadow_CameraFar#)
	
	ModelMatrixID=CreateMatrix4()
	SetIdentityMatrix4(ModelMatrixID)
	LightMVPMatrixID=CreateMatrix4()
	Multiply2Matrix4(LightMVPMatrixID,ModelMatrixID,ViewMatrixID)
	Multiply2Matrix4(LightMVPMatrixID,ProjectionMatrixID,LightMVPMatrixID)
	
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",0,GetMatrix4Element(LightMVPMatrixID,0),GetMatrix4Element(LightMVPMatrixID,4),GetMatrix4Element(LightMVPMatrixID,8),GetMatrix4Element(LightMVPMatrixID,12))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",1,GetMatrix4Element(LightMVPMatrixID,1),GetMatrix4Element(LightMVPMatrixID,5),GetMatrix4Element(LightMVPMatrixID,9),GetMatrix4Element(LightMVPMatrixID,13))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",2,GetMatrix4Element(LightMVPMatrixID,2),GetMatrix4Element(LightMVPMatrixID,6),GetMatrix4Element(LightMVPMatrixID,10),GetMatrix4Element(LightMVPMatrixID,14))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",3,GetMatrix4Element(LightMVPMatrixID,3),GetMatrix4Element(LightMVPMatrixID,7),GetMatrix4Element(LightMVPMatrixID,11),GetMatrix4Element(LightMVPMatrixID,15))

	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",0,GetMatrix4Element(LightMVPMatrixID,0),GetMatrix4Element(LightMVPMatrixID,4),GetMatrix4Element(LightMVPMatrixID,8),GetMatrix4Element(LightMVPMatrixID,12))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",1,GetMatrix4Element(LightMVPMatrixID,1),GetMatrix4Element(LightMVPMatrixID,5),GetMatrix4Element(LightMVPMatrixID,9),GetMatrix4Element(LightMVPMatrixID,13))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",2,GetMatrix4Element(LightMVPMatrixID,2),GetMatrix4Element(LightMVPMatrixID,6),GetMatrix4Element(LightMVPMatrixID,10),GetMatrix4Element(LightMVPMatrixID,14))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",3,GetMatrix4Element(LightMVPMatrixID,3),GetMatrix4Element(LightMVPMatrixID,7),GetMatrix4Element(LightMVPMatrixID,11),GetMatrix4Element(LightMVPMatrixID,15))

	DeleteMatrix4(ModelMatrixID)
	//~ DeleteMatrix4(ViewMatrixID)
	DeleteMatrix4(ProjectionMatrixID)
	DeleteMatrix4(LightMVPMatrixID)
endfunction
*/

function Shadow_SetSunDirection(DirX#,DirY#,DirZ#)
	SetVector3(Shadow_SunVectorID,DirX#,DirY#,DirZ#)
	NormalizeVector3(Shadow_SunVectorID)
endfunction

function Shadow_Update()
	for ObjectID=0 to Shadow_ObjectID.length
		SetObjectCullMode(Shadow_ObjectID[ObjectID],2)
		SetObjectShader(Shadow_ObjectID[ObjectID],Shadow_DepthShaderID)
	next ObjectID

	Shadow_UpdateFrustumVertices()
	
	SetRenderToImage(0,Shadow_DepthRenderImageID)
	Update3D(0)
	ClearScreen()
	Render3D()
	
	for ObjectID=0 to Shadow_ObjectID.length
		SetObjectCullMode(Shadow_ObjectID[ObjectID],1)
		SetObjectShader(Shadow_ObjectID[ObjectID],Shadow_ShadowShaderID)
	next ObjectID
	
	SetRenderToScreen()
endfunction

function Shadow_UpdateFrustumVertices()
	CameraVectorID=CreateVector3(GetCameraX(1),GetCameraY(1),GetCameraZ(1))
	NearLeftTopVectorID=CreateVector3(Get3DVectorXFromScreen(0,0),Get3DVectorYFromScreen(0,0),Get3DVectorZFromScreen(0,0))
	FarLeftTopVectorID=CreateVector3(GetVector3X(NearLeftTopVectorID)*Shadow_Distance#,GetVector3Y(NearLeftTopVectorID)*Shadow_Distance#,GetVector3Z(NearLeftTopVectorID)*Shadow_Distance#)
	GetVector3Add(NearLeftTopVectorID,CameraVectorID)
	GetVector3Add(FarLeftTopVectorID,CameraVectorID)

	NearRightTopVectorID=CreateVector3(Get3DVectorXFromScreen(GetDeviceWidth(),0),Get3DVectorYFromScreen(GetDeviceWidth(),0),Get3DVectorZFromScreen(GetDeviceWidth(),0))
	FarRightTopVectorID=CreateVector3(GetVector3X(NearRightTopVectorID)*Shadow_Distance#,GetVector3Y(NearRightTopVectorID)*Shadow_Distance#,GetVector3Z(NearRightTopVectorID)*Shadow_Distance#)
	GetVector3Add(NearRightTopVectorID,CameraVectorID)
	GetVector3Add(FarRightTopVectorID,CameraVectorID)
	
	NearLeftBottomVectorID=CreateVector3(Get3DVectorXFromScreen(0,GetDeviceHeight()),Get3DVectorYFromScreen(0,GetDeviceHeight()),Get3DVectorZFromScreen(0,GetDeviceHeight()))
	FarLeftBottomVectorID=CreateVector3(GetVector3X(NearLeftBottomVectorID)*Shadow_Distance#,GetVector3Y(NearLeftBottomVectorID)*Shadow_Distance#,GetVector3Z(NearLeftBottomVectorID)*Shadow_Distance#)
	GetVector3Add(NearLeftBottomVectorID,CameraVectorID)
	GetVector3Add(FarLeftBottomVectorID,CameraVectorID)
	
	NearRightBottomVectorID=CreateVector3(Get3DVectorXFromScreen(GetDeviceWidth(),GetDeviceHeight()),Get3DVectorYFromScreen(GetDeviceWidth(),GetDeviceHeight()),Get3DVectorZFromScreen(GetDeviceWidth(),GetDeviceHeight()))
	FarRightBottomVectorID=CreateVector3(GetVector3X(NearRightBottomVectorID)*Shadow_Distance#,GetVector3Y(NearRightBottomVectorID)*Shadow_Distance#,GetVector3Z(NearRightBottomVectorID)*Shadow_Distance#)
	GetVector3Add(NearRightBottomVectorID,CameraVectorID)
	GetVector3Add(FarRightBottomVectorID,CameraVectorID)

	DeleteVector3(CameraVectorID)

	local VectorID as integer[7]
	VectorID[0]=NearLeftTopVectorID
	VectorID[1]=FarLeftTopVectorID
	VectorID[2]=NearRightTopVectorID
	VectorID[3]=FarRightTopVectorID
	VectorID[4]=NearLeftBottomVectorID
	VectorID[5]=FarLeftBottomVectorID
	VectorID[6]=NearRightBottomVectorID
	VectorID[7]=FarRightBottomVectorID
	
	//~ if GetRawKeyPressed(70)=1
		//~ for i=0 to 7
			//~ String$=String$+str(GetVector3X(VectorID[i]))+", "+str(GetVector3Y(VectorID[i]))+", "+str(GetVector3Z(VectorID[i]))+chr(10)
		//~ next i
		//~ message(String$)
	//~ endif

	Shadow_MinX#=GetVector3X(VectorID[0])
	Shadow_MinY#=GetVector3Y(VectorID[0])
	Shadow_MinZ#=GetVector3Z(VectorID[0])
	Shadow_MaxX#=GetVector3X(VectorID[0])
	Shadow_MaxY#=GetVector3Y(VectorID[0])
	Shadow_MaxZ#=GetVector3Z(VectorID[0])
	
	for ID=1 to 7
		if GetVector3X(VectorID[ID])>Shadow_MaxX#
			Shadow_MaxX#=GetVector3X(VectorID[ID])
		elseif GetVector3X(VectorID[ID])<Shadow_MinX#
			Shadow_MinX#=GetVector3X(VectorID[ID])
		endif
		if GetVector3Y(VectorID[ID])>Shadow_MaxY#
			Shadow_MaxY#=GetVector3Y(VectorID[ID])
		elseif GetVector3Y(VectorID[ID])<Shadow_MinY#
			Shadow_MinY#=GetVector3Y(VectorID[ID])
		endif
		if GetVector3Z(VectorID[ID])>Shadow_MaxZ#
			Shadow_MaxZ#=GetVector3Z(VectorID[ID])
		elseif GetVector3Z(VectorID[ID])<Shadow_MinZ#
			Shadow_MinZ#=GetVector3Z(VectorID[ID])
		endif
	next ID
	
	DeleteVector3(NearLeftTopVectorID)
	DeleteVector3(FarLeftTopVectorID)
	DeleteVector3(NearRightTopVectorID)
	DeleteVector3(FarRightTopVectorID)
	DeleteVector3(NearLeftBottomVectorID)
	DeleteVector3(FarLeftBottomVectorID)
	DeleteVector3(NearRightBottomVectorID)
	DeleteVector3(FarRightBottomVectorID)

	Shadow_MaxZ#=Shadow_MaxZ#+10

	//~ if GetRawKeyPressed(70)=1
		//~ message(str(Shadow_MinX#)+", "+str(Shadow_MinY#)+", "+str(Shadow_MinZ#))
		//~ message(str(Shadow_MaxX#)+", "+str(Shadow_MaxY#)+", "+str(Shadow_MaxZ#))
	//~ endif

	CenterX#=(Shadow_MinX#+Shadow_MaxX#)*0.5
	CenterY#=(Shadow_MinY#+Shadow_MaxY#)*0.5
	CenterZ#=(Shadow_MinZ#+Shadow_MaxZ#)*0.5
	Width#=Shadow_MaxX#-Shadow_MinX#
	Height#=Shadow_MaxY#-Shadow_MinY#
	Depth#=Shadow_MaxZ#-Shadow_MinZ#

	SetVector3(Shadow_AtVectorID,CenterX#,CenterY#,CenterZ#)
	GetVector3Add(Shadow_AtVectorID,Shadow_SunVectorID)
	SetVector3(Shadow_EyeVectorID,CenterX#,CenterY#,CenterZ#)
	ViewMatrixID=BuildLookAtLhMatrix4(Shadow_AtVectorID,Shadow_EyeVectorID)

	//~ if GetRawKeyPressed(70)=1
		//~ for i=0 to 16 step 4
			//~ String$=String$+str(GetMatrix4Element(ViewMatrixID,0+i))+", "+str(GetMatrix4Element(ViewMatrixID,1+i))+", "+str(GetMatrix4Element(ViewMatrixID,2+i))+", "+str(GetMatrix4Element(ViewMatrixID,3+i))+chr(10)
		//~ next i
		//~ message(String$)
	//~ endif

	//~ ViewMatrixID=CreateMatrix4()
	//~ CenterVectorID=CreateVector3(CenterX#,CenterY#,CenterZ#)
	//~ InvertedMatrixID=CreateMatrix4()
	//~ 
	//~ Inverse2Matrix4(ViewMatrixID)
	//~ TransformCoordsVector3(CenterVectorID,InvertedMatrixID)
	//~ TranslateMatrix4(ViewMatrixID,CenterX#,CenterY#,CenterZ#)

	ProjectionMatrixID=creatematrix4()
	OrthographicProjectionMatrix4(ProjectionMatrixID,Width#,Height#,Shadow_CameraNear#,Depth#)
	
	ModelMatrixID=CreateMatrix4()
	SetIdentityMatrix4(ModelMatrixID)
	LightMVPMatrixID=CreateMatrix4()
	Multiply2Matrix4(LightMVPMatrixID,ModelMatrixID,ViewMatrixID)
	Multiply2Matrix4(LightMVPMatrixID,ProjectionMatrixID,LightMVPMatrixID)
	
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",0,GetMatrix4Element(LightMVPMatrixID,0),GetMatrix4Element(LightMVPMatrixID,4),GetMatrix4Element(LightMVPMatrixID,8),GetMatrix4Element(LightMVPMatrixID,12))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",1,GetMatrix4Element(LightMVPMatrixID,1),GetMatrix4Element(LightMVPMatrixID,5),GetMatrix4Element(LightMVPMatrixID,9),GetMatrix4Element(LightMVPMatrixID,13))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",2,GetMatrix4Element(LightMVPMatrixID,2),GetMatrix4Element(LightMVPMatrixID,6),GetMatrix4Element(LightMVPMatrixID,10),GetMatrix4Element(LightMVPMatrixID,14))
	SetShaderConstantArrayByName(Shadow_DepthShaderID,"LightMVPVector",3,GetMatrix4Element(LightMVPMatrixID,3),GetMatrix4Element(LightMVPMatrixID,7),GetMatrix4Element(LightMVPMatrixID,11),GetMatrix4Element(LightMVPMatrixID,15))

	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",0,GetMatrix4Element(LightMVPMatrixID,0),GetMatrix4Element(LightMVPMatrixID,4),GetMatrix4Element(LightMVPMatrixID,8),GetMatrix4Element(LightMVPMatrixID,12))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",1,GetMatrix4Element(LightMVPMatrixID,1),GetMatrix4Element(LightMVPMatrixID,5),GetMatrix4Element(LightMVPMatrixID,9),GetMatrix4Element(LightMVPMatrixID,13))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",2,GetMatrix4Element(LightMVPMatrixID,2),GetMatrix4Element(LightMVPMatrixID,6),GetMatrix4Element(LightMVPMatrixID,10),GetMatrix4Element(LightMVPMatrixID,14))
	SetShaderConstantArrayByName(Shadow_ShadowShaderID,"LightMVPVector",3,GetMatrix4Element(LightMVPMatrixID,3),GetMatrix4Element(LightMVPMatrixID,7),GetMatrix4Element(LightMVPMatrixID,11),GetMatrix4Element(LightMVPMatrixID,15))

	//~ DeleteVector3(CenterVectorID)
	//~ DeleteMatrix4(InvertedMatrixID)
	DeleteMatrix4(ModelMatrixID)
	DeleteMatrix4(ViewMatrixID)
	DeleteMatrix4(ProjectionMatrixID)
	DeleteMatrix4(LightMVPMatrixID)
endfunction