1. physics.addBehavior(new GravityBehavior(new Vec2D(0, 0.5)));
2. physics.addBehavior(new ConstantForceBehavior(new Vec2D(0.2, 0)));
   

1. preserving the length between the particles (I don't want the blades of grass to look like elastic bands).
2. giving the particle string some rotational stiffness (so that it can counteract the net force of the wind and gravity).

1. float length = 10;
2. double theta = -Math.PI / 3
3. position = new Vec2D(100, 100);
4. 
   
5. float endX = (float) (length * Math.cos(theta)) + position.x;
6. float endY = (float) (length * Math.sin(theta)) + position.y;
7. 
   
8. Vec2D end = new Vec2D(endX, endY);
9. lines.add(new Line2D(position, end));

1.     ControlP5 controlP5 = new ControlP5(this);
2.     // add a new controller window.
3.     ControlWindow cw = controlP5.addControlWindow("Controls", 250, 250);
4.     cw.setLocation(10, 10);
5.     cw.hideCoordinates();
6.     // add some tabs
   
7.     cw.addTab("noise");
8.     cw.addTab("cliffs");
9.     // start adding controls to noise tab
   
10.     controlP5.begin(controlP5.getTab("noise"), 20, 20);
11.     controlP5.addSlider("division width", 0, 30).linebreak();
12.     controlP5.addSlider("noise height", 0, height).linebreak();
13.     controlP5.addSlider("noise factor", 0, 0.1f).linebreak();
14.     controlP5.addSlider("noise detail", 0, 10).linebreak();
15.     controlP5.end();

What have I missed in the way I did this? I'm sure it's something silly.

1. enum StarType {
2.   sPOINT,
3.   sCROSS,
4.   sBURST,
5.   sNOVA
6. };