; ; Copyright (c) 2005 IBM Corporation and others. ; All rights reserved. This program and the accompanying materials ; are made available under the terms of the Common Public License v1.0 ; which accompanies this distribution, and is available at ; http://www.eclipse.org/legal/cpl-v10.html ; ; Contributors: ; IBM - Initial implementation ; ; The Vision representation deals with some simple aspects ; of vision. ; ; agent looks at object. event LookAt(agent,object) ; agent sees object. fluent See(agent,object) ; An effect axiom states that if an agent looks at ; an object, the agent will see the object: [agent,object,time] Initiates(LookAt(agent,object), See(agent,object), time). ; A precondition axiom states that for ; an agent to look at an object, ; there must be a location such that ; the agent is at the location and ; the object is at the location, or ; there must be a door such that ; the agent is near the door, ; the object is near the door, and ; the door is open: ;[agent,object,time] ;Happens(LookAt(agent,object),time) -> ;({location} ; HoldsAt(At(agent,location),time) & ; HoldsAt(At(object,location),time))| ;({door} ; HoldsAt(NearPortal(agent,door),time) & ; HoldsAt(NearPortal(object,door),time) & ; HoldsAt(DoorIsOpen(door),time)). ; An effect axiom states that if an agent ; looks at an object, the agent will no longer ; see other objects: [agent,object1,object2,time] object1!=object2 -> Terminates(LookAt(agent,object1), See(agent,object2), time). ; Several effect axioms state that if an ; agent walks through a door, up a staircase, or down a staircase, ; the agent no longer sees an object: [agent,door,object,time] Terminates(WalkThroughDoor12(agent,door), See(agent,object), time). [agent,door,object,time] Terminates(WalkThroughDoor21(agent,door), See(agent,object), time). [agent,door,object,time] Terminates(WalkUpStaircase(agent,door), See(agent,object), time). [agent,door,object,time] Terminates(WalkDownStaircase(agent,door), See(agent,object), time). ; End of file.