forked from: forked from: forked from: flash on 2009-5-30
forked from forked from: forked from: flash on 2009-5-30 (diff: 81)
ActionScript3 source code
/**
* Copyright lab9 ( http://wonderfl.net/user/lab9 )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/9e9V
*/
package
{
import flash.display.Graphics;
import flash.display.Sprite;
import flash.events.MouseEvent;
import flash.geom.Point;
import flash.geom.Rectangle;
import flash.text.TextField;
import flash.text.TextFormat;
import flash.utils.getTimer;
[SWF(frameRate="100", backgroundColor="0xFFFFFF", width="500", height="500")]
public class TriangleSpeedTest2 extends Sprite
{
public var outputText : TextField;
public function TriangleSpeedTest2()
{
super();
outputText = new TextField();
x = y = 250;
outputText.defaultTextFormat = new TextFormat("Arial");
outputText.textColor = 0x0000FF;
outputText.text = "Click to start test";
outputText.x = outputText.y = -250;
outputText.width = 500;
addChild(outputText);
stage.addEventListener(MouseEvent.MOUSE_DOWN, startTest);
}
// I'm thinking that storing these values as properties rather than declaring them as local vars
// should be faster...
private var x0 : Number;
private var y0 : Number;
private var x1 : Number;
private var y1 : Number;
private var x2 : Number;
private var y2 : Number;
private var l : Number;
private var r : Number;
private var t : Number;
private var b : Number;
private var t0 : int;
private var t1 : int;
private var t2 : int;
private var s : Number
private var lm0 : Number
private var lm1 : Number
private var lm2 : Number
private var rm0 : Number
private var rm1 : Number
private var rm2 : Number
private var top_intersection:Number ;
private var bottom_intersection : Number;
private var toptrianglepoint : Number;
private var bottomtrianglepoint : Number;
private var m: Number;
private var c : Number
private var m0: Number;
private var c0 : Number
private var m1: Number;
private var c1 : Number
private var m2: Number;
private var c2 : Number
// THESE ARE THE TWO FUNCTIONS YOU CAN OPTIMISE.
// I realise that you could inline the lineRectangleIntersect method, but I'd rather not do that just yet...
// I'm looking for maths/logic improvements.
public function triangleTest(rect:Rectangle, vertex0:Point, vertex1:Point, vertex2:Point ) : Boolean
{
// YOU MUST LEAVE THESE DECLARATIONS; they simulate necessary data exchange within PV3D
l = rect.left;
r = rect.right;
t = rect.top;
b = rect.bottom;
x0 = vertex0.x;
y0 = vertex0.y;
x1 = vertex1.x;
y1 = vertex1.y;
x2 = vertex2.x;
y2 = vertex2.y;
if (x0 > l) if(x0 < r) if(y0 > t) if(y0 < b) return true;
if (x1 > l) if( x1 < r ) if( y1 > t ) if( y1 < b) return true;
if (x2 > l ) if( x2 < r ) if( y2 > t ) if( y2 < b) return true;
//if (isInsideTriangle(x0, y0, x1, y1, x2, y2)) return true;
return (isIntersecting(x0, y0, x1, y1) || isIntersecting(x1, y1, x2, y2) || isIntersecting(x0, y0, x2, y2));
}
public function isInsideTriangle(x0: Number,y0: Number,x1: Number,y1: Number,x2: Number,y2: Number):Boolean
{
// Calculate m and c for the equation for the line (y = mx+c)
m0 = (y2-y1) / (x2-x1);
c0 = y2 -(m0 * x2);
m1 = (y2-y0) / (x2-x0);
c1 = y0 -(m1 * x0);
m2 = (y1-y0) / (x1-x0);
c2 = y0 -(m2 * x0);
t0 = int(x0 * m0 + c0 > y0);
t1 = int(x1 * m1 + c1 > y1);
t2 = int(x2 * m2 + c2 > y2);
lm0 = l * m0 + c0;
lm1 = l * m1 + c1;
lm2 = l * m2 + c2;
rm0 = r * m0 + c0;
rm1 = r * m1 + c1;
rm2 = r * m2 + c2;
if ( !(t0 ^ int( lm0 > t)) && !(t1 ^ int(lm1 > t)) && !(t2 ^ int(lm2 > t))) return true;
if (!(t0 ^ int( lm0 > b)) && !(t1 ^ int(lm1 > b)) && !(t2 ^ int(lm2 > b))) return true;
if ( !(t0 ^ int( rm0 > t)) && !(t1 ^ int(rm1 > t)) && !(t2 ^ int(rm2 > t))) return true;
if (!(t0 ^ int( rm0 > b)) && !(t1 ^ int(rm1 > b)) && !(t2 ^ int(rm2 > b))) return true;
return false;
}
public function isIntersecting(xa: Number,ya: Number,xb: Number,yb: Number):Boolean
{
// Calculate m and c for the equation for the line (y = mx+c)
m = (yb-ya) / (xb-xa);
c = ya -(m * xa);
if ((ya - t) * (yb - t) < 0)
{
s = (t - c) / m;
if ( s > l && s < r) return true;
}
if ((ya - b) * (yb - b) < 0)
{
s = (b - c) / m;
if ( s > l && s < r) return true;
}
if ((xa - l) * (xb - l) < 0)
{
s = m * l + c;
if ( s > t && s < b) return true
}
if ((xa - r) * (xb - r) < 0)
{
s = m * r + c
if ( s > t && s < b) return true;
}
return false;
}
public function startTest(e:MouseEvent = null) : void
{
var g : Graphics = graphics;
g.clear();
var cullingRect : Rectangle = new Rectangle(-100,-75,200,150);
var iterations : int = 100000;
var timerIntersecting : int = 0 ;
var timerNotIntersecting : int = 0 ;
var intersectCount : int = 0;
var v0 : Point = new Point();
var v1 : Point = new Point();
var v2 : Point = new Point();
var i : int = iterations;
while(--i>-1)
{
v0.x = Math.random()*400 - 200;
v0.y = Math.random()*400 - 200;
v1.x = v0.x+ (Math.random()*300 -150);
v1.y = v0.y+ (Math.random()*300 -150);
v2.x = v0.x+ (Math.random()*300 -150);
v2.y = v0.y+ (Math.random()*300 -150);
var startTimer : int = getTimer();
var intersecting : Boolean = triangleTest(cullingRect, v0, v1, v2);
if(intersecting)
{
timerIntersecting += (getTimer() - startTimer);
intersectCount++;
}
else
{
timerNotIntersecting += (getTimer() - startTimer);
}
if(i<300)
{
g.lineStyle(0,0x000000);
g.beginFill(intersecting ? 0x006600 : 0x660000,0.5);
g.moveTo(x0,y0);
g.lineTo(x1,y1);
g.lineTo(x2,y2);
g.lineTo(x0,y0);
g.endFill();
}
}
g.lineStyle(0,0xffffff,0.5);
g.drawRect(cullingRect.x, cullingRect.y, cullingRect.width, cullingRect.height);
outputText.text = "Average time per triangle : "+(timerIntersecting+timerNotIntersecting)/iterations;
outputText.appendText("\nAverage time per intersecting triangle : "+(timerIntersecting)/intersectCount);
outputText.appendText("\nAverage time per non-intersecting triangle : "+(timerNotIntersecting)/(iterations-intersectCount));
}
}
}