Class TPhysCalcs

java.lang.Object
  |
  +--TPhysCalcs

class TPhysCalcs

extends java.lang.Object

implements java.lang.Runnable

Class that does all the physical simulations and caries all the physical objects.

Field Summary

boolean	Active Activity flag
double	ALPHA0 Initial angle of the first pendulum in radians
TArc3D	Arc3D1 Arc between LinePendul1 and the first pendulum
TArc3D	Arc3D2 Arc between LinePendul2 and the second pendulum
double	BETA0 Initial angle of the second pendulum in radians
double	C Distance between suspension point of the pendulum and suspension point of the spring ON the pendulum
double	CM2AXIS Distance between center of mass and suspension point of the pendula
double	DEPTHPENDUL Depth of the pendula
double	e_max Maximum error in the simulation
double	G Gravitational constant
double	h_maxinit Initial maximum stepsize (for use in adaptive stepsize)
double	HEIGHTPENDUL Initial Height of the pendula
double	K Initial spring constant K
TLine3D	LinePendul1 Line going through the first pendulum when it is at rest.
TLine3D	LinePendul2 Line going through the second pendulum when it is at rest.
double	MASS Initial mass of the pendula
int	NOTIMES Initial number of steps the simulation does between two frames
(package private) TOscilloscope	Oscilloscope Oscilloscope canvas.
TPendulum	Pendul1 First pendulum
int	Pendul1DataStream Datastream index of the first pendulum, used to identify the data for the first pendulum in the oscilloscope
TPendulum	Pendul2 Second pendulum
int	Pendul2DataStream Datastream index of the second pendulum, used to identify the data for the second pendulum in the oscilloscope
double	perframe Number of seconds per frame
(package private) TPhysCanvas	PhysCanvas Canvas onto which all the physical objects are drawn.
TSphere3D	Sphere1 Sphere at the top of the first pendulum (suspension point)
TSphere3D	Sphere2 Sphere at the top of the second pendulum (suspension point)
TSpiral3D	Spiral Spring between the two pendula
double	t Time of the simulation (in milliseconds
protected java.lang.Thread	timerThread Thread used for calculating and predrawing the physics of the simulation.
double	VPendul1 Angular velocity of the first pendulum
double	VPendul2 Angular velocity of the second pendulum
double	WIDTHPENDUL Width of the pendula

Constructor Summary

(package private)

TPhysCalcs() The constructor of the class.

Method Summary

double	Accel(double _a) Angular acceleration of a single pendulum
double	Accel(double _a, double _b) Angular acceleration off the pendula.
void	activateChanges() After a parameter is changed this routine is called.
double	atan(double _alpha) Java's arctangens is only defined in a certain range of points, this is a work around for angles > 0.5 PI
void	estimateStepsize() Use adaptive stepsize velocity verlet on 1 period of simulation of a single pendulum.
double	Inertia() The Inertia of the pendula
void	initGraphics() Call the initGraphics of both canvases.
void	run() This routine is called when a thread is started for this class.
void	setActive() Set Active true
void	setInactive() Set Active false
void	start() start the simulation by setting both canvases to active, and opening a new thread that calls the run method.
void	stop() stop the simulation by setting both canvases to inactive, and shutting down the thread.
void	switchActive() When called this routine switches the state of the simulation.

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

Pendul1

public TPendulum Pendul1

First pendulum

Pendul2

public TPendulum Pendul2

Second pendulum

Spiral

public TSpiral3D Spiral

Spring between the two pendula

Arc3D1

public TArc3D Arc3D1

Arc between LinePendul1 and the first pendulum

Arc3D2

public TArc3D Arc3D2

Arc between LinePendul2 and the second pendulum

Sphere1

public TSphere3D Sphere1

Sphere at the top of the first pendulum (suspension point)

Sphere2

public TSphere3D Sphere2

Sphere at the top of the second pendulum (suspension point)

LinePendul1

public TLine3D LinePendul1

Line going through the first pendulum when it is at rest.

LinePendul2

public TLine3D LinePendul2

Line going through the second pendulum when it is at rest.

PhysCanvas

TPhysCanvas PhysCanvas

Canvas onto which all the physical objects are drawn.

Oscilloscope

TOscilloscope Oscilloscope

Oscilloscope canvas.

timerThread

protected java.lang.Thread timerThread

Thread used for calculating and predrawing the physics of the simulation.

Pendul1DataStream

public int Pendul1DataStream

Datastream index of the first pendulum, used to identify the data for the first pendulum in the oscilloscope

Pendul2DataStream

public int Pendul2DataStream

Datastream index of the second pendulum, used to identify the data for the second pendulum in the oscilloscope

t

public double t

Time of the simulation (in milliseconds

VPendul1

public double VPendul1

Angular velocity of the first pendulum

VPendul2

public double VPendul2

Angular velocity of the second pendulum

e_max

public double e_max

Maximum error in the simulation

h_maxinit

public double h_maxinit

Initial maximum stepsize (for use in adaptive stepsize)

perframe

public double perframe

Number of seconds per frame

NOTIMES

public int NOTIMES

Initial number of steps the simulation does between two frames

MASS

public double MASS

Initial mass of the pendula

ALPHA0

public double ALPHA0

Initial angle of the first pendulum in radians

BETA0

public double BETA0

Initial angle of the second pendulum in radians

K

public double K

Initial spring constant K

HEIGHTPENDUL

public double HEIGHTPENDUL

Initial Height of the pendula

WIDTHPENDUL

public double WIDTHPENDUL

Width of the pendula

DEPTHPENDUL

public double DEPTHPENDUL

Depth of the pendula

CM2AXIS

public double CM2AXIS

Distance between center of mass and suspension point of the pendula

G

public double G

Gravitational constant

C

public double C

Distance between suspension point of the pendulum and suspension point of the spring ON the pendulum

Active

public boolean Active

Activity flag

Constructor Detail

TPhysCalcs

TPhysCalcs()

The constructor of the class. It initializes all the physical components

Method Detail

atan

public double atan(double _alpha)

Java's arctangens is only defined in a certain range of points, this is a work around for angles > 0.5 PI

Parameters:

_alpha - The angle in radians for which the arctangens should be calculated

activateChanges

public void activateChanges()

After a parameter is changed this routine is called. It resets all physical elements.

switchActive

public void switchActive()

When called this routine switches the state of the simulation. If it runs, it gets paused, if it is paused it will start runnign again.

initGraphics

public void initGraphics()

Call the initGraphics of both canvases. These initialize the canvas. Initialize the double buffering, a standard technique used in computer animations to get a flicker free image.

start

public void start()

start the simulation by setting both canvases to active, and opening a new thread that calls the run method.

stop

public void stop()

stop the simulation by setting both canvases to inactive, and shutting down the thread.

run

public void run()

This routine is called when a thread is started for this class. It runs until the thread is killed

Specified by:

run in interface java.lang.Runnable

Accel

public double Accel(double _a,
                    double _b)

Angular acceleration off the pendula.

Parameters:

_a - the deviation from the equilibrium position of the pendulum for which the acceleration should be calculated

_b - the deviation from the equilibrium position of the other pendulum

Accel

public double Accel(double _a)

Angular acceleration of a single pendulum

Parameters:

_a - the deviation from the equilibrium position of the pendulum

setActive

public void setActive()

Set Active true

setInactive

public void setInactive()

Set Active false

Inertia

public double Inertia()

The Inertia of the pendula

estimateStepsize

public void estimateStepsize()

Use adaptive stepsize velocity verlet on 1 period of simulation of a single pendulum. The smallest stepsize used is the stepsize that is going to be used by the rest of the simulation.