function SPHSystem(){
    this.particles = [];
	
    /**
     * Density of the system (kg/m3).
     * @property {number} density
     */
    this.density = 1;
	
    /**
     * Distance below which two particles are considered to be neighbors.
     * It should be adjusted so there are about 15-20 neighbor particles within this radius.
     * @property {number} smoothingRadius
     */
    this.smoothingRadius = 1;
    this.speedOfSound = 1;
	
    /**
     * Viscosity of the system.
     * @property {number} viscosity
     */
    this.viscosity = 0.01;
    this.eps = 0.000001;

    // Stuff Computed per particle
    this.pressures = [];
    this.densities = [];
    this.neighbors = [];
}
Smoothed-particle hydrodynamics system
@class SPHSystem
@constructor