forked from: Robot Arm

by taka_milk 24 Dec 2008

• Forked from wanson's Robot Arm
• Diff: 5
• Related works: 6
Embed

// forked from Wanson's Robot Arm
package  {
    import flash.display.*;
    import flash.events.Event;
    import flash.geom.Point;

    [SWF(width="500", height="500", backgroundColor="0xFFFFFF", frameRate="24")]  
    public class Program extends Sprite {
        private var screen:Sprite;
        private const NARM:int = 4;
        private const LENGTH:Number = 58;
        private var angles:Array;
        private var arms:Array;
        private var effector1:Sprite;
        private var effector2:Sprite;

        public function Program() {
            this.screen = this;
            var i:int;
            var g:Graphics;

            angles = new Array();
            arms = new Array();
            for (i = 0; i < NARM; i++) {
                angles[i] = 0.0;
                arms[i] = new Sprite();
                g = arms[i].graphics;
                g.lineStyle(1, 0);
                g.drawRoundRect(-8, -8, LENGTH + 16, 16, 16);
                g.drawCircle(0, 0, 3);
                g.drawCircle(0, 0, 8);
                screen.addChild(arms[i]);
            }

            effector1 = new Sprite();
            effector2 = new Sprite();
            g = effector1.graphics;
            g.lineStyle(1, 0);
            g.drawRect(-5, -5, 30, 10);
            g.drawRect(20, -10, 5, 15);
            g.drawCircle(0, 0, 8);
            g = effector2.graphics;
            g.lineStyle(1, 0);
            g.drawRect(-5, -5, 30, 10);
            g.drawRect(20, -5, 5, 15);
            g.drawCircle(0, 0, 3);
            screen.addChild(effector1);
            screen.addChild(effector2);


            addEventListener(Event.ENTER_FRAME, onEnterFrame);
        }

        public function onEnterFrame(ev:Event):void {
            draw();
        }

        private var ph:Number = 0;
        public function draw():void {
            var i:int;
            var x:Number;
            var y:Number;

            var e:Point;
            for (i = 0; i < 10; i++)
                e = pursuit(0, new Point(250, 250), new Point(screen.mouseX, screen.mouseY));

            x = y = 250;
            for (i = 0; i < NARM; i++) {
                arms[i].x = x;
                arms[i].y = y;
                arms[i].rotation = angles[i] / Math.PI * 180;
                x += LENGTH * Math.cos(angles[i]);
                y += LENGTH * Math.sin(angles[i]);
            }

            var dx:Number = e.x - screen.mouseX;
            var dy:Number = e.y - screen.mouseY;
            if (dx * dx + dy * dy < 50)
                ph += 0.1;
            var angle_e:Number = arms[NARM - 1].rotation;
            var angle_ed:Number = 25 + 30 * Math.pow(Math.sin(ph), 2);
            effector1.x = effector2.x = e.x - Math.cos(angles[NARM - 1]) * 25;
            effector1.y = effector2.y = e.y - Math.sin(angles[NARM - 1]) * 25;
            effector1.rotation = angle_e + angle_ed;
            effector2.rotation = angle_e - angle_ed;
        }

        private function pursuit(bi:uint, o:Point, p:Point):Point {
            var e:Point;
            if (bi < NARM - 1) {
                const o2:Point = new Point(
                        o.x + Math.cos(angles[bi]) * LENGTH,
                        o.y + Math.sin(angles[bi]) * LENGTH);
                e = pursuit(bi + 1, o2, p);
            } else {
                e = new Point(
                        o.x + Math.cos(angles[bi]) * (LENGTH + 20),
                        o.y + Math.sin(angles[bi]) * (LENGTH + 20));
            }

            if ((e.y == o.y && e.x == o.x) || (p.y == o.y && p.x == o.x))
                return e;

            const anglee:Number = Math.atan2(e.y - o.y, e.x - o.x);
            const anglep:Number = Math.atan2(p.y - o.y, p.x - o.x);
            var angle_d:Number = (anglep - anglee);

            if (angle_d > Math.PI) angle_d = angle_d - 2 * Math.PI;
            else if (angle_d < -Math.PI) angle_d = angle_d + 2 * Math.PI;	
            if (angle_d > 0.025) angle_d = 0.025;
            else if (angle_d < -0.025) angle_d = -0.025;
            angles[bi] += angle_d;

            return e;
        }
    }
}