1. 1 5. Behavior Objects  Both interaction and animation are specified with objects  Both interaction and animation are specified with Behavior objects  A object changes the scene graph in response to events  A Behavior object changes the scene graph in response to events –key presses, mouse moves, object collisions, passage of time, etc. Interactions BG TG Shape Behavior

2. 2 Some Behavior Classes v v KeyNavigatorBehavior   MouseBehavior  User-defined classes  User-defined Behavior classes –triggered by objects –triggered by WakeupCondition objects – –PickMouseBehavior – –Interpolator

3. 3 WakeupConditions v mouse, keyboard input v collision v time and frame change v object movement v camera movement v sensor activity (input devices)

4. 4 Picking Image plane Object in the world Mouse pointer Pick ray User

5. 5 Interaction(Stimulus and Action)

6. 6 SceneGraph(Interaction) B mouse S BG TG S S S Locale VitualUniverse object view sphere base bottom arm up arm robot arm environment BG root group time TG

7. 7 Behavior object v Billboard v Interpolator v LOD(Level of Detail) v KeyNavigatorBehavior v MouseBehavior v PickMouseBehavior v User-defined Behavior class –Stimulus : WakeupCondition object –Action : processStimulus member function

8. 8 WakeupCondition object v Mouse,Keyboard input –WakeupOnAWTEvent v Collision –WakeupOnCollisionEntry –WakeupOnCollisionExit –WakeupOnCollisionMovement v Time and Frames –WakeupOnElapsedTime –WakeupOnElapsedFrames

9. 9 WakeupCondition object v Object Movement –WakeupOnTransformChange v View(camera movement) –WakeupOnActivation, WakeupOnDeactivation –WakeupOnViewPlatformEntry, WakeupOnViewPlatfromExit v Sensor(other input device) –WakeupOnSensorEntry,WakeupOnSensorExit v Behavior –WakeupOnBehaviorPost