Category Archives: misc

Fish Curve

By Zevan | May 13, 2010
CLICK HERE TO COPY
Actionscript:
  1. var xp:Number = 0;
  2. var yp:Number = 0;
  3. var t:Number = 0;
  4. var a:Number = 200;
  5. x = stage.stageWidth / 2;
  6. y = stage.stageHeight / 2;
  7.  
  8. graphics.lineStyle(0,0x000000);
  9. addEventListener(Event.ENTER_FRAME, onRun);
  10. function onRun(evt:Event):void {
  11.     xp = a * Math.cos(t) - (a * Math.pow(Math.sin(t),2))/Math.sqrt(2);
  12.     yp = a * Math.cos(t) * Math.sin(t);
  13.     if (t == 0){
  14.       graphics.moveTo(xp, yp);
  15.     }else{
  16.       graphics.lineTo(xp, yp);
  17.     }
  18.     t += 0.05;
  19. }

While surfing mathworld I stumbled upon the equation for something called the Fish Curve. This snippet will draw something like this:

Also posted in Math | Tagged , , | Leave a comment

Astroid Pedal Curve Variation

By Zevan | May 12, 2010
CLICK HERE TO COPY
Actionscript:
  1. var xp:Number = 0;
  2. var yp:Number = 0;
  3. var t:Number = 0;
  4. var r:Number = 200;
  5. x = stage.stageWidth / 2;
  6. y = stage.stageHeight / 2;
  7.  
  8. graphics.lineStyle(0,0x000000);
  9. addEventListener(Event.ENTER_FRAME, onRun);
  10. function onRun(evt:Event):void {
  11.     r = 200 * Math.cos(t / 10);
  12.     xp = r * Math.pow(Math.cos(t), 3);
  13.     yp = r * Math.pow(Math.sin(t), 3);
  14.     if (t == 0){
  15.       graphics.moveTo(xp, yp);
  16.     }else{
  17.       graphics.lineTo(xp, yp);
  18.     }
  19.     t += 0.1;
  20. }

While browsing mathworld I decided to do a variation on this curve . The above snippet will draw something like this:

Also posted in Math | Tagged , , | Leave a comment

Circle Mouse Toy

By Zevan | April 24, 2010
CLICK HERE TO COPY
Actionscript:
  1. var circles:Array = [];
  2. for (var i:int = 0; i<30; i++){
  3.     var c:Sprite = makeCircle();
  4.     c.x = stage.stageWidth / 2;
  5.     c.y = stage.stageHeight / 2;
  6.     c.scaleX = 1 + i/2;
  7.     c.scaleY = 0.5 + i/4;
  8.     addChild(c);
  9.     circles.push(c);
  10. }
  11. addEventListener(Event.ENTER_FRAME, onLoop);
  12. function onLoop(evt:Event):void {
  13.     circles[0].y += (mouseY - circles[0].y) / 4;
  14.     for (var i:int = 1; i<circles.length; i++){
  15.         var pre:Sprite = circles[i - 1];
  16.         circles[i].y += (pre.y - circles[i].y) / 4;
  17.     }
  18. }
  19. function makeCircle():Sprite{
  20.     var s:Sprite = new Sprite();
  21.     with(s.graphics){
  22.         lineStyle(0,0x000000);
  23.         drawCircle(0,0,10);
  24.     }
  25.     return s;
  26. }

This morning I woke up with a vision of this simple mouse toy in my head. I decided I might as well code it up... I may do more simple things like this in the next few days, it's relaxing.

Also posted in Graphics, motion | Tagged , , | 5 Comments

Logistic Map Play

By Zevan | March 27, 2010
CLICK HERE TO COPY
Actionscript:
  1. var offX:Number = 100;
  2. var offY:Number = 300;
  3. var scalarX:Number = 6;
  4. var scalarY:Number = 200;
  5. addEventListener(Event.ENTER_FRAME, onLoop);
  6. function onLoop(evt:Event):void{
  7.     var r:Number = mouseY / 100;
  8.     var xn:Number = (mouseX - 100) / 650;
  9.     var xn1:Number = 0;
  10.     graphics.clear();
  11.     graphics.lineStyle(0,0);
  12.     for (var i:int = 0; i<100; i++){
  13.       xn1 = r * xn * (1 - xn);
  14.       xn = xn1;
  15.       if (i == 0){
  16.         graphics.moveTo(offX+i*scalarX,offY+xn1*scalarY);  
  17.       }else{
  18.         graphics.lineTo(offX+i*scalarX, offY+xn1*scalarY);
  19.       }
  20.     }
  21. }

Whenever I can't decide what kind of snippet to make, I simply go to wikipedia or mathworld for a bit and I always end up with something. I've messed with Logistic Maps before (when learning about strange attractors). This is a simple rendering where the x and y axis change the biotic potential (r) and the starting value for x.

Here is the link I used for reference.


Have a look at the swf (just move your mouse around).

Also posted in Graphics, Math | Tagged , , | 2 Comments