 			var i:uint, p:Particle;
 			// reset forces
 			for (i = _particles.length; --i >= 0; ) {
-				p = _particles[i] as Particle;
+				p = _particles[i];
 				p.fx = p.fy = 0;
 			}
 			// collect forces

package flare.physics
{
	/**
	 * A physical simulation involving particles, springs, and forces.
	 * Useful for simulating a range of physical effects or layouts.

		private var _springs:Array = new Array();
		private var _forces:Array = new Array();
		private var _integrator:IIntegrator = new RK4Integrator();
		private var _bounds:Rectangle = null;
		
		/** The default gravity force for this simulation. */
		public function get gravityForce():GravityForce {
