
Re: Arranging disks (or any object for that matter) be
Posted:
Apr 13, 2013 8:36 PM


Clif,
(This should replace my earlier posting so as to use Turtles instead of Disks in the SetterBar heading.)
The previous Presentations solution can be easily modified for this.
<< Presentations`
I scale the turtle down so it can walk basically on a unit circle.
turtleShape = {Darker[Green], Thickness[1/32], Circle[{1, .7}, .5, {8 Pi/6, 3 Pi/2}], EdgeForm[Directive[Thick, White]], Disk[{1, 0}, .5, {0, Pi}], Disk[{0, 0}, 1, {0, Pi}], Disk[{.5, 0}, .25, {Pi, 2 Pi}], Disk[{.5, 0}, .25, {Pi, 2 Pi}], White, Disk[{1.2, .3}, .04]} // ScaleOp[1/5, {0, 0}];
This provides the dynamic, again with a completely fixed background. Each turtle is rotated and then translated into position. I added a circle as a base for the turtles, who are arrayed clockwise about the circle.
DynamicModule[{numDisks = 0, angle = 0}, pagelet[ phrase["Number of Turtles:", Spacer[10], SetterBar[ Dynamic[numDisks, (numDisks = #; angle = 2 \[Pi]/Max[1, numDisks]) &], Range[0, 9]]], Draw2D[ {{GrayLevel[0.5], ComplexCircle[0, 0.96]}, Dynamic@ Table[ turtleShape // RotateOp[(nn  1) angle  \[Pi]/2, {0, 0}] // TranslateOp[ToCoordinates[Exp[I (nn  1) angle]]], {nn, 1, numDisks}]}, PlotRange > 1.5, Background > LightBrown, ImageSize > 500] ] ]
David Park djmpark@comcast.net http://home.comcast.net/~djmpark/index.html
From: Clif McInnis [mailto:c_mcinnis@hotmail.com]
Bob,
Thank you, that works very well. I am wondering if it is possible to put an object in the place of the disk. I have a little turtle shape (the code below)that I had tried to substitute for the line " Disk[{Cos[a], Sin[a]}, 3/Max[8, n]]" which did not work out too well. My guess is that it would work if I would assign the {x,y} values of the semi disk that makes the shell to Cos[a],Sin[a] and then related the other parts of the shape to those coordinates, however before I undertook that endeavor I thought that I would just ask you to give me a yes/no answer as to whether it would even be a possibility. Again Thank You for your help.
Sincerely  Clifton McInnis
Graphics[{ Darker[Green], Thickness[1/32], Circle[{1, .7}, .5, {8 Pi/6, 3 Pi/2}], EdgeForm[Directive[Thick, White]], Disk[{1, 0}, .5, {0, Pi}], Disk[{0, 0}, 1, {0, Pi}], Disk[{.5, 0}, .25, {Pi, 2 Pi}], Disk[{.5, 0}, .25, {Pi, 2 Pi}], White, Disk[{1.2, .3}, .04]}]

