1 /**
  2  * Abstract; see an implementing class.
  3  *
  4  * @class Represents a force that acts on particles. Note that this interface
  5  * does not specify how to bind a force to specific particles; in general,
  6  * forces are applied globally to all particles. However, some forces may be
  7  * applied to specific particles or between particles, such as spring forces,
  8  * through additional specialization.
  9  *
 10  * @see pv.Simulation
 11  * @see pv.Particle
 12  * @see pv.Force.charge
 13  * @see pv.Force.drag
 14  * @see pv.Force.spring
 15  */
 16 pv.Force = {};
 17 
 18 /**
 19  * Applies this force to the specified particles.
 20  *
 21  * @function
 22  * @name pv.Force.prototype.apply
 23  * @param {pv.Particle} particles particles to which to apply this force.
 24  * @param {pv.Quadtree} q a quadtree for spatial acceleration.
 25  */
 26