Helping my nephew with collision detection

[randysiler at mac.com]

Hi All,
	I'm helping my nephew (13) get started writing a game in Squeak 
(trying to move him more into the joy of writing games rather than 
playing games) and he has made some great strides but has a problem he 
can't get through. I'd like to help him but at this point the extent of 
my wisdom is pointing him at Squeak. If any of you could give us a hint 
about how to proceed we'd both greatly appreciate it.

	Starting from the "make a car" tutorial Byron has now made a tank and 
a steering wheel  and some balls that he wants to bounce back and forth 
between two walls. He's quite exceited about the cool games he could 
create trying to drive the tank through a field where these bullets are 
bouncing back and forth and he has discovered that he needs collision 
detection But we haven't been able to implement it yet. Currently he 
has his balls (bullets) bouncing backand forth from the top and bottom 
of the Squeak world but we can't get them to bounce off the walls he 
has made.

	I've told him that I think Squeak has collision detection but it is a 
little beyond me to actually show him how. It seems like we want to 
write a test where the ball decides if it is touching a wall. We see 
"touches" but we can't get it to allow us to say touches the wall.


	If any of you can help us we'd appreciate it. Thanks.

Randy and Byron.