ANN Nine ball pool

[Jim Hurley]

>
>Message: 5
>Date: Thu, 24 Mar 2005 23:15:21 +0100
>From: "MisterX" <b.xavier at internet.lu>
>Subject: RE: ANN Nine ball pool
>To: "'How to use Revolution'" <use-revolution at lists.runrev.com>
>Message-ID: <20050324221752.A06DB93005D at mail.runrev.com>
>Content-Type: text/plain;	charset="US-ASCII"
>
>
>Awesome!
>
>As a pool shark, I must say I liked it for the "physics"!
>
>Although the snooker color balls is not really 9 ball and the green felt was
>hurting my eyes after a few shots.... Getting old I guess! ;)
>
>The pockets, are well, eh, non standard but...
>
>But hey, Im sure socket ricochets are no misteries for you now
>so we can play online :)
>
>yep, awesome, keep it coming!!!
>
>Check out the old pool game animations in MAME... Should give you some
>ideas. There were awesome games of pool for a quarter!


Thanks for the kind words. And thanks for the tip about MAME. I 
Googled it and found a Mac download but it was 10 megs. I live out in 
the boonies, the foothills of the Sierra Nevada Mts., with only a 
phone line connection.

The only enhancement I was considering was to use the arrow keys to 
allow for spin: top, back, right, left.

There are a number of occasions when it is impossible to position the 
cue ball for the next shot without spin.

Glad you liked the physics. Me too. I am a retired physics teacher. 
The interesting thing about collisions between two ball, one of which 
is initially at rest, is that the trajectories of the two ball after 
the collision are orthogonal--a necessary consequence of conservation 
of energy and momentum. (Assuming the same mass for each.)  This was 
new to me. See "What's inside" for the details.

The tangential components of the velocities are unchanged when two 
*moving* balls collide elastically. By adding spin, it would be 
possible to give an extra push in the tangential directions. And of 
course top spin and back spin to give a little push or pull in the 
radial direction--the line joining the centers.

Jim