<html><head><style type="text/css"></style></head><body><div style="font-family:times new roman,new york,times,serif;font-size:12pt"><div>And, if you are interested in this kind of UI, you might want to take a look at the first great pen based system (GRAIL at RAND ca 1966-69) which used all of those devices. Cheers, Alan </div><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"> <div style="font-family: arial,helvetica,sans-serif; font-size: 10pt;"><hr size="1">From: Gary C Martin <gary@garycmartin.com> To: forster@ozonline.com.au Cc: iaep <iaep@lists.sugarlabs.org> Sent: Tuesday, February 10, 2009 6:25:21 AM Subject: Re: [IAEP] [Sur] Turtle Art Portfolio v-7 On 10 Feb 2009, at 10:54, <a ymailto="mailto:forster@ozonline.com.au" href="mailto:forster@ozonline.com.au">forster@ozonline.com.au</a> wrote: > Edward >> With these arithmetic tiles and square root, I can do all of  >> Euclidean >> synthetic plane geometry and all of plane analytic geometry up to.... >> > You will still rapidly run into limitations with TA. > > The canvas effectively limits the number of tiles you can have in  > your program, scroll bars would help if they didn't overly  > complicate things Well, keeping code short/simple is a good skill to learn :-) But if  there is desire to move in this direction it might be worth looking at  'containers'. Think of it as a little like code folding, where you can  collapse N bricks down into a single 'container' brick which has the  correct brick connect shapes for it's inputs and outputs. Screen space  would still be an issue (when expanding) so you would want to go for a  'drill down' type UI interaction where double clicking a container  would just show you it's tiles (and you'd need an out button to get  out of a container). Actually a special container type could be a nice metaphor for holding/ embedding an actual python source editor. Double clicking it (source  container) would simple show you a floating source editor window  instead of bricks, clicking the out button would put you back with the  bricks. > Execution speed seems to become a problem at about the point where  > you fill up the canvas, both regarding moving a stack of blocks and  > running your program. I ran into all three limitations doing a lunar  > lander at <a href="http://tonyforster.blogspot.com/2009/02/turtle-lander.html" target="_blank">http://tonyforster.blogspot.com/2009/02/turtle-lander.html</a>  > and for that reason haven't implemented crash detection (vspeed,  > hspeed or terrain flatness) A nested container metaphor should keep the complexity of any single  brick layer view more reasonable. --Gary >> My next request is a While loop. >> > Can't you use > > forever > If <condition> > stop stack > > to get the same as while? > > Tony > _______________________________________________ > IAEP -- It's An Education Project (not a laptop project!) > <a ymailto="mailto:IAEP@lists.sugarlabs.org" href="mailto:IAEP@lists.sugarlabs.org">IAEP@lists.sugarlabs.org</a> > <a href="http://lists.sugarlabs.org/listinfo/iaep" target="_blank">http://lists.sugarlabs.org/listinfo/iaep</a> _______________________________________________ IAEP -- It's An Education Project (not a laptop project!) <a ymailto="mailto:IAEP@lists.sugarlabs.org" href="mailto:IAEP@lists.sugarlabs.org">IAEP@lists.sugarlabs.org</a> <a href="http://lists.sugarlabs.org/listinfo/iaep" target="_blank">http://lists.sugarlabs.org/listinfo/iaep</a> </div></div></div> </body></html>