Hi, I've made a behavior class to navigate in my simple universe but I have a problem. The navigator can go through the object (the wall, the table, etc). Does somebody can explain me how to catch the collision between the viewer and the rest of the universe and avoid them. Thank you François Savard Département de Génie Civil/ Civil Engineering Departement Université Laval Québec/Canada =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".