Class pv.Simulation

Represents a particle simulation. Particles are massive points in two-dimensional space. Forces can be applied to these particles, causing them to move. Constraints can also be applied to restrict particle movement, for example, constraining particles to a fixed position, or simulating collision between circular particles with area.

The simulation uses Position Verlet integration, due to the ease with which geometric constraints can be implemented. For each time step, Verlet integration is performed, new forces are accumulated, and then constraints are applied.

The simulation makes two simplifying assumptions: all particles are equal-mass, and the time step of the simulation is fixed. It would be easy to incorporate variable-mass particles as a future enhancement. Variable time steps are also possible, but are likely to introduce instability in the simulation.

This class can be used directly to simulate particle interaction. Alternatively, for network diagrams, see pv.Layout.Force.
Defined in: Simulation.js.

Class Summary
Constructor Attributes	Constructor Name and Description
	pv.Simulation(particles) Constructs a new simulation for the specified particles.

Field Summary
Field Attributes	Field Name and Description
	constraints The constraints in the simulation.
	forces The forces in the simulation.
	particles The particles in the simulation.

Method Summary
Method Attributes	Method Name and Description
	constraint(c) Adds the specified constraint to the simulation.
	force(f) Adds the specified force to the simulation.
	particle(p) Adds the specified particle to the simulation.
	stabilize(n) Apply constraints, and then set the velocities to zero.
	step() Advances the simulation one time-step.

Class Detail

pv.Simulation(particles)

Constructs a new simulation for the specified particles.

Parameters:
{array} particles: an array of pv.Particles to simulate.

See:: pv.Layout.Force; pv.Force; pv.Constraint

Field Detail

{pv.Constraint} constraints

The constraints in the simulation. Constraints are stored as a linked list; this field represents the first constraint in the simulation.

{pv.Force} forces

The forces in the simulation. Forces are stored as a linked list; this field represents the first force in the simulation.

{pv.Particle} particles

The particles in the simulation. Particles are stored as a linked list; this field represents the first particle in the simulation.

Method Detail

{pv.Simulation} constraint(c)

Adds the specified constraint to the simulation.

Parameters:
{pv.Constraint} c: the new constraint.

Returns:: {pv.Simulation} this.

{pv.Simulation} force(f)

Adds the specified force to the simulation.

Parameters:
{pv.Force} f: the new force.

Returns:: {pv.Simulation} this.

{pv.Simulation} particle(p)

Adds the specified particle to the simulation.

Parameters:
{pv.Particle} p: the new particle.

Returns:: {pv.Simulation} this.

{pv.Simulation} stabilize(n)

Apply constraints, and then set the velocities to zero.

Parameters:
n

Returns:: {pv.Simulation} this.

step()

Advances the simulation one time-step.

Classes

Class pv.Simulation