3d adventure, interacting with objects, types,

This should give you a starting point. I would store the type handle in the entityname and the type instance can be easily retreived using the Object command ...

Note that by using STR$() to display the type instance you can see all the associated field values.

Hope this helps.

Graphics3D 640,480,16,1

Global Camera = CreateCamera()
PositionEntity Camera,0,50,0
RotateEntity Camera,90,0,0

Global Highlight = CreateCube()
ScaleEntity Highlight, 2, 2, 2
EntityAlpha Highlight,.5
HideEntity Highlight

Const ID_NPC = 1
Const ID_Light = 2
Const ID_Container = 3

Global CURRENT.GameObject	;selected object

Type GameObject
	Field Name$
	Field Entity
	Field ID
	Field Otherstuff
End Type

;set up some objects
For l = 1 To 20
	test.GameObject = GAMEOBJECTcreate( Rand(1,3) , Rand(-50,50), 0 , Rand(-50,50 ) )
Next

While Not KeyDown(1)

	GAMEOBJECTpick()
	RenderWorld()
	DISPLAY()
	Flip

Wend

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Function DISPLAY()

	Color 255,255,255
	Oval MouseX()-5,MouseY()-5,11,11,0
	
	Text 0,0,"Selected Object : "
	If CURRENT<>Null 
		Text 0,20,Str$(CURRENT) 
	Else
		Text 0,20,"Nothing"
	End If
		
End Function

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Function GAMEOBJECTpick()

	MR = MouseDown(1)
	ML = MouseDown(2)
	If MR Or ML
		CameraPick( Camera , MouseX(), MouseY() )
		GAMEOBJECTinteract( PickedEntity() )
	End If
	
End Function

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Function GAMEOBJECTcreate.GameObject( ID , x#, y#, z# )

	g.GameObject = New GameObject
	g\ID = ID
	Select g\ID
		Case ID_NPC
			g\Name = "Non Player Character"
			g\Entity = CreateCube()
			EntityColor g\Entity,200,100,100
		Case ID_Light
			g\Name = "Light"
			g\Entity = CreateCylinder()
			EntityColor g\Entity,100,200,100
		Case ID_Container
			g\Name = "Container"
			g\Entity = CreateSphere()
			EntityColor g\Entity,100,100,200
	End Select

	EntityPickMode g\Entity , 2
	PositionEntity g\Entity, x, y, z
	NameEntity g\Entity, Handle( g )
	
	Return g
	
End Function

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Function GAMEOBJECTinteract( Picked )

	If Picked > 0
		ShowEntity Highlight
		PositionEntity Highlight, EntityX( picked ), EntityY( picked ), EntityZ( picked )
		CURRENT = Object.GameObject( EntityName( Picked ))
		Select CURRENT\ID
			Case ID_NPC
				;reaction
			Case ID_Light
				;reaction
			Case ID_Container
				;reaction
		End Select		
	Else
		HideEntity Highlight
		CURRENT = Null
	EndIf

End Function