Category Archives: Vector

Utils3D.projectVectors() Lathe

By Zevan | July 6, 2009
CLICK HERE TO COPY
Actionscript:
  1. [SWF(width = 500, height = 500, backgroundColor = 0x000000)]
  2. var halfWidth:Number = stage.stageWidth / 2;
  3. var halfHeight:Number = stage.stageHeight / 2;
  4. var loc:Vector.<Number>;
  5.  
  6. graphics.lineStyle(0, 0xFF0000);
  7. graphics.moveTo(halfWidth, 0);
  8. graphics.lineTo(halfWidth, stage.stageHeight);
  9. graphics.moveTo(0, halfHeight);
  10. graphics.lineTo(stage.stageWidth, halfHeight);
  11.  
  12. var line:Shape = Shape(addChild(new Shape()));
  13. line.x = halfWidth;
  14.  
  15. var idle:Function = function(){};
  16. var currentMode:Function = idle;
  17. stage.addEventListener(MouseEvent.MOUSE_DOWN, onDown);
  18. stage.addEventListener(MouseEvent.MOUSE_UP, onUp);
  19. addEventListener(Event.ENTER_FRAME, onLoop);
  20. function onDown(evt:MouseEvent):void{
  21.     if (contains(frame)){
  22.         removeChild(frame);
  23.         currentMode = idle;
  24.         line.graphics.clear();
  25.         return;
  26.     }
  27.     loc = new Vector.<Number>();
  28.     line.graphics.lineStyle(0,0xFFFFFF);
  29.     line.x = halfWidth
  30.     line.y = halfHeight;
  31.     line.graphics.moveTo(line.mouseX, line.mouseY);
  32.     currentMode = captureLocs;
  33.     canvas.fillRect(canvas.rect, 0x000000);
  34. }
  35. function onUp(evt:MouseEvent):void{
  36.     if (currentMode == idle) return;
  37.     setupLathe();
  38.     currentMode = showLathe;
  39. }
  40.  
  41. function onLoop(evt:Event):void{
  42.     currentMode();
  43. }
  44. function captureLocs():void{
  45.     loc.push(line.mouseX);
  46.     loc.push(line.mouseY);
  47.     loc.push(0);
  48.     line.graphics.lineTo(line.mouseX, line.mouseY);
  49. }
  50. /**
  51.  -- Lathe Stuff:
  52. */
  53. var canvas:BitmapData = new BitmapData(stage.stageWidth, stage.stageHeight,false, 0x000000);
  54. var frame:Bitmap = new Bitmap(canvas);
  55. var dx:Number=0;
  56. var dy:Number=0;
  57.  var matrix:Matrix3D = new Matrix3D();
  58. var pVerts:Vector.<Number>;
  59. var uvts:Vector.<Number>;
  60. function setupLathe():void{
  61.     addChild(frame);
  62.     pVerts =  new Vector.<Number>();
  63.     uvts = new Vector.<Number>();
  64.     var nVerts:Vector.<Number> = new Vector.<Number>();
  65.     var tVerts:Vector.<Number> = new Vector.<Number>();
  66.     matrix.identity();
  67.     var step:Number = 2;
  68.     for (var i:int = 0; i <360; i+=step){
  69.         matrix.appendRotation(step,Vector3D.Y_AXIS);
  70.         matrix.transformVectors(loc, tVerts);
  71.         nVerts = nVerts.concat(tVerts);
  72.     }
  73.     loc = nVerts.concat();
  74. }
  75. function showLathe():void{
  76.     dx += (mouseX - dx)/4;
  77.     dy += (mouseY - dy)/4;
  78.     matrix.identity();
  79.     matrix.appendRotation(dy,Vector3D.X_AXIS);
  80.     matrix.appendRotation(dx,Vector3D.Y_AXIS);
  81.     matrix.appendTranslation(halfWidth, halfHeight, 0);
  82.     Utils3D.projectVectors(matrix, loc, pVerts, uvts);
  83.     canvas.lock();
  84.     canvas.fillRect(canvas.rect, 0x000000);
  85.     var leng:int = pVerts.length;
  86.     for (var i:int = 0; i<leng; i+=2){
  87.         canvas.setPixel( pVerts[i], pVerts[i + 1], 0xFFFFFF);
  88.     }
  89.     canvas.unlock();
  90. }

This snippet allows you to create 3D lathe shapes by drawing a 2D line. This is done using Utils3D.projectVectors() and Matrix.transformVectors().

Have a look at the swf here...

Also posted in 3D, BitmapData, Math, graphics algorithms, matrix, setPixel | Tagged , , | 3 Comments

setVector() CA Texture

By Zevan | July 1, 2009
CLICK HERE TO COPY
Actionscript:
  1. [SWF(width=500, height=500)]
  2. var canvasSize:int=stage.stageWidth;
  3. var canvas:BitmapData=new BitmapData(canvasSize,canvasSize,false,0x000001);
  4. addChild(new Bitmap(canvas, "auto", true));
  5. var size:int=canvas.width*canvas.height - canvasSize;
  6. var pixels:Vector.<uint>=canvas.getVector(canvas.rect);
  7. for (var i:int = 0; i<canvasSize; i++) {
  8.     var xp:int=int(Math.random()*canvasSize);
  9.     var yp:int=int(Math.random()*canvasSize);
  10.     pixels[xp+yp*canvasSize]=0xFF000000;
  11. }
  12. var targetCol:uint=0xFF000000;
  13. var buffer:Vector.<uint>=pixels.concat();
  14. var fade:uint=1;
  15.  
  16. addEventListener(Event.ENTER_FRAME, onLoop);
  17. function onLoop(evt:Event):void {
  18.     var curr:uint=targetCol;
  19.     var r:int = (curr>> 16) & 0xFF;
  20.     var g:int = (curr>> 8) & 0xFF;
  21.     var b:int=curr&0xFF;
  22.     r+=fade;
  23.     g+=fade;
  24.     b+=fade;
  25.     if (r>255) r=255;
  26.     if (g>255) g=255;
  27.     if (b>255) b=255;
  28.     var darker:uint=0xFF000000|r<<16|g<<8|b;
  29.     if (darker==0xFFFFFFFF) {
  30.         removeEventListener(Event.ENTER_FRAME, onLoop);
  31.     }
  32.     for (var i:int = canvasSize; i<size; i++) {
  33.         curr=pixels[i];
  34.         if (curr==targetCol) {
  35.             var index:int=i-canvasSize+int(Math.random()*3) - 1;
  36.             if (index>0) buffer[index]=darker;
  37.             if (int(Math.random()*50)==1) {
  38.                 index=i-canvasSize+int(Math.random()*3)-1;
  39.                 if (index>0) buffer[index]=darker;
  40.             }
  41.         }
  42.     }
  43.     targetCol=darker;
  44.     canvas.lock();
  45.     canvas.setVector(canvas.rect, buffer);
  46.     pixels=buffer.concat();
  47.     canvas.unlock();
  48. }

This snippet uses setVector() to draw something that looks like this:

This is a cellular automaton. It has kind of a strange rule set - but you could easily use this snippet to do more traditional cellular automata.

Also posted in BitmapData, pixel manipulation | Tagged , , | Leave a comment

x and y Coordinates in 1D Array / Vector

By Zevan | June 14, 2009
CLICK HERE TO COPY
Actionscript:
  1. var canvas:BitmapData=new BitmapData(400,400,false,0x000000);
  2. addChild(new Bitmap(canvas));
  3. var pix:Vector.<uint>=canvas.getVector(canvas.rect);
  4.  
  5. canvas.lock();
  6. for (var i:int = 0; i<300; i++) {
  7.     var xp:int=50+i;
  8.     var yp:int=50+i/2;
  9.     // target x and y coords in 1D array
  10.     pix[xp+yp*400]=0xFFFFFF;
  11. }
  12. canvas.setVector(canvas.rect, pix);
  13. canvas.unlock();

This snippet shows how to target x and y coordinates in a 1D Array / Vector. This can be useful sometimes when working with setVector().

This is sort of like re-inventing setPixel().... and for that reason is kind of pointless - that said, it's interesting to know. I first learned about this technique from using processing.

Also posted in BitmapData, arrays, pixel manipulation, setPixel | Tagged , , | Leave a comment

IGraphicsData Example

By Zevan | June 13, 2009
CLICK HERE TO COPY
Actionscript:
  1. // note the high framerate for testing purposes
  2. [SWF(width = 800, height = 600, frameRate=60)]
  3. // red, yellow, blue
  4. var fills:Vector.<IGraphicsData> = Vector.<IGraphicsData>([new GraphicsSolidFill(0xFF0000),  new GraphicsSolidFill(0xFFCC00), new GraphicsSolidFill(0x0033FF)]);
  5.  
  6. var stroke:IGraphicsData = new GraphicsStroke();
  7.  
  8. var cmds:Vector.<int> = new Vector.<int>();
  9. var ci:int = 0;
  10. var dat:Vector.<Number> = new Vector.<Number>();
  11. var di:int = 0;
  12. var igraph:Vector.<IGraphicsData> = new Vector.<IGraphicsData>();
  13. var ig:int  = 0;
  14. var path:Vector.<GraphicsPath> = new Vector.<GraphicsPath>();
  15. var boxNum:int = 1500;
  16. var locX:Vector.<Number> = new Vector.<Number>(boxNum);
  17. var locY:Vector.<Number> = new Vector.<Number>(boxNum);
  18. var velX:Vector.<Number> = new Vector.<Number>(boxNum);
  19. var velY:Vector.<Number> = new Vector.<Number>(boxNum);
  20. var cols:int = 50;
  21. for (var i:int = 0; i<boxNum; i++){
  22.     path[i] = new GraphicsPath(new Vector.<int>(), new Vector.<Number>());
  23.     path[i].winding = GraphicsPathWinding.NON_ZERO;
  24.     var theta:Number = i * Math.PI/180;
  25.     var sin:Number = Math.cos(theta);
  26.     var cos:Number =  Math.sin(theta);
  27.     var r:Number = Math.random()*100;
  28.     var vr:Number = r * 0.05;
  29.     velX[i] = vr * cos;
  30.     velY[i] = vr * sin;
  31.     locX[i] = 400 + r * cos;
  32.     locY[i] = 300 + r * sin;
  33. }
  34.  
  35. // box vars
  36. var xp:Number, yp:Number, size:Number, hs:Number;
  37. // corners
  38. var x0:Number, y0:Number, x1:Number, y1:Number;
  39.  
  40. addEventListener(Event.ENTER_FRAME, onLoop);
  41. function onLoop(evt:Event):void {
  42.     graphics.clear();
  43.     ig = 0;
  44.     for (i= 0; i<boxNum; i++){
  45.         // inline function:
  46.         locX[i] += velX[i];
  47.         locY[i] += velY[i];
  48.         xp = locX[i];
  49.         yp = locY[i];
  50.         if (xp <0 || xp> 800){
  51.             velX[i] *= -1;
  52.         }
  53.         if (yp <0 || yp> 600){
  54.             velY[i] *= -1;
  55.         }
  56.         size = 10 + i % 10;
  57.         hs = size * 0.5;
  58.         x0 = xp - hs, y0 = yp - hs;
  59.         x1 = xp + hs, y1 = yp + hs;
  60.         ci = 0;
  61.         di = 0;
  62.         cmds = path[i].commands;
  63.         dat = path[i].data;
  64.         // GraphicsPathCommand.MOVE_TO
  65.         cmds[ci++] = 1;
  66.         dat[di++] = x0 , dat[di++] = y0;
  67.         // GraphicsPathCommand.LINE_TO
  68.         cmds[ci++] = 2;
  69.         dat[di++] = x1 , dat[di++] = y0;
  70.         // GraphicsPathCommand.LINE_TO
  71.         cmds[ci++] = 2;
  72.         dat[di++] = x1 , dat[di++] = y1;
  73.         // GraphicsPathCommand.LINE_TO
  74.         cmds[ci++] = 2;
  75.         dat[di++] = x0 , dat[di++] = y1;
  76.         // end inline function
  77.          
  78.         path[i].commands = cmds;
  79.         path[i].data = dat;
  80.         igraph[ig++] = fills[i % 3];
  81.         igraph[ig++] = path[i];
  82.     }
  83.     // everything is drawn with one function call
  84.     graphics.drawGraphicsData(igraph);
  85. }

I haven't spent much time with IGraphicsData. It's a very cool feature and I think its going to take me awhile to realize its full potential. Since I have to start somewhere I decided to write this snippet to show that it is rather fast. I also recalled reading some benchmark info for the new fp10 graphics stuff over at bytearray.org.... pretty nice info there...

This snippet is pretty optimized, there are a few areas (such as the recurring population of the cmds Vector) that could be optimized more but are left this way for SOME flexibility.

Also posted in Graphics, misc, motion | Tagged , , | Leave a comment