# What's New - September 2001

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September 28: 2001:   I'm still alive - working a few hours per day on the Roller Coaster Simulator project.  I think it's going to be  a good one.  I keep spending time playing with it when  I should be working on it.    One of the final problems was calculating centripetal forces for hills, dips and loops.   The force for a body turning is inversely proportional to the radius being turned  (e.g. cut the radius in half - double the force).    The problem of determining the radius lead to this Math Topics page   "Define a circle given 3 points"  which tests  the functions used in the Coaster project.

September 16:  Still sorting out emotions from Tuesday's tragedy.  Mainly anger and frustration at those who would make us less free.  Have they thought this all the way through?  I think not.

I spent a few  days this week working on a QuickSort demo program that would explain itself as it sorted.  As a result I understand the QuickSort algorithm pretty well, but not because of any program output.  Too much text is as bad as none.   Maybe an animated sort would be more instructive.  Anyway, back to the drawing board on that project.

Here's a Simple Gravity Cart program written as a test-bed for a planned roller coaster simulation.    This cart knows how to accelerate downhill and decelerate uphill and slow down both ways due to friction.   It took a long time to teach it to stay on the track, now I have to teach it to fall off the track if gravity dictates.  Still, enough physics and animation techniques here to make it interesting.

September 7:2001:  The customized cursors page that I promised a couple of weeks ago has been posted in Delphi Techniques.   Not a biggie, but if you're doing customized cursors, or want to include pictures, multimedia files, or other data  as part of your executable module, this page will give you a starting point.

September 5: 2001:  Happy 1st Anniversary!

Almost missed it but  Delphi For Fun went online one year ago yesterday.    7000 home page visitors and 34,000 sessions, whatever those are,  later, we're still going strong with a bigger backlog  than ever.    For what it's worth, here are the stats from the first year of operation.  Now if only  my net worth chart  looked this good ...

OK, back to trying to figure out why my new Delphi web program works fine locally but gives me an "Internal Server Error" when I try it here.   (Update - Oops -  since DFF is hosted on a Unix system, we're out of luck re running Delphi apps remotely, unless I find a Windows hosting service or get Kylix).

 Red loses

September 2, 2001:  Here's another Martin Gardner invention - the Game of Hip, first published way back when everyone knew what the word "hipster" meant -  as in "hipsters" avoid "squares".

It's a two-player game with the objective not to complete 4 corners of any square with your tokens.  This version supports both human and computer opponents.  There's trick that makes it easy to win (or at least not lose, a tie is possible). But it is a fun mental geometrical exercise anyway.