com.threerings.media.util

Class ArcPath

java.lang.Object

com.threerings.media.util.TimedPath

com.threerings.media.util.ArcPath

All Implemented Interfaces:

Path

public class ArcPath
extends TimedPath

The line path is used to cause a pathable to go from point A to point B along the arc of an ellipse in a certain number of milliseconds.

Field Summary

Fields

Modifier and Type	Field and Description
static int	FINE An orientation constant indicating that the fine (sixteen) directions should be used to orient the pathable being made to follow this path.
static int	NONE An orientation indicating that the pathable should not be oriented as it moves along the path.
static int	NORMAL An orientation constant indicating that the normal (eight) directions should be used to orient the pathable being made to follow this path.

Constructor Summary

Constructors

Constructor and Description
ArcPath(Point start, double xradius, double yradius, double sangle, double delta, long duration, int orient) Creates an arc path that will animate a pathable from the specified starting position along an ellipse defined by the supplied parameters.

Method Summary

Modifier and Type	Method and Description
static void	computePosition(Point center, double xradius, double yradius, double angle, Point pos) Computes the position of an entity along the path defined by the supplied parameters assuming that it must finish the path in the specified duration (in millis) and has been traveling the path for the specified number of elapsed milliseconds.
Point	getEndPos() Returns the position of the end of the path.
Path	getTranslatedInstance(int x, int y) Return a copy of the path, translated by the specified amounts.
void	paint(Graphics2D gfx) Paint this path on the screen (used for debugging purposes only).
void	setOrientOffset(int offset) Sets the offset that is applied to the pathable whenever it is oriented.
boolean	tick(Pathable pable, long timestamp) Called to request that this path update the position of the specified pathable based on the supplied timestamp information.

Methods inherited from class com.threerings.media.util.TimedPath

fastForward, init, toString, wasRemoved

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NORMAL

public static final int NORMAL

An orientation constant indicating that the normal (eight) directions should be used to orient the pathable being made to follow this path.

See Also:

Constant Field Values

FINE

public static final int FINE

An orientation constant indicating that the fine (sixteen) directions should be used to orient the pathable being made to follow this path.

See Also:

Constant Field Values

NONE

public static final int NONE

An orientation indicating that the pathable should not be oriented as it moves along the path.

See Also:

Constant Field Values

Constructor Detail

ArcPath

public ArcPath(Point start,
               double xradius,
               double yradius,
               double sangle,
               double delta,
               long duration,
               int orient)

Creates an arc path that will animate a pathable from the specified starting position along an ellipse defined by the supplied parameters. The pathable will travel the specified number of radians along the arc of that ellipse. A positive number of radians indicates counter-clockwise travel along the circle, a negative number, clockwise rotation.

Parameters:

start - the starting point for the pathable.

xradius - the length of the x radius.

yradius - the length of the y radius.

sangle - the starting angle.

delta - the angle through which the pathable should be moved.

duration - the number of milliseconds during which to effect the animation.

orient - an orientation code indicating how the pathable should be oriented when following the path, either NORMAL, or FINE.

Method Detail

getTranslatedInstance

public Path getTranslatedInstance(int x,
                                  int y)

Return a copy of the path, translated by the specified amounts.

setOrientOffset

public void setOrientOffset(int offset)

Sets the offset that is applied to the pathable whenever it is oriented. This offset is in clockwise units whose granularity is specified by the NORMAL or FINE setting supplied to the path at construct time. The intent here is to allow arc paths to be applied that don't orient the pathable in the direction they are traveling but instead in some fixed offset from that direction.

getEndPos

public Point getEndPos()

Returns the position of the end of the path.

tick

public boolean tick(Pathable pable,
                    long timestamp)

Description copied from interface: Path

Called to request that this path update the position of the specified pathable based on the supplied timestamp information. A path should record its initial timestamp and determine the progress of the pathable along the path based on the time elapsed since the pathable began down the path.

Parameters:

pable - the pathable whose position should be updated.

timestamp - the timestamp associated with this frame.

Returns:

true if the pathable's position was updated, false if the path determined that the pathable should not move at this time.

paint

public void paint(Graphics2D gfx)

Description copied from interface: Path

Paint this path on the screen (used for debugging purposes only).

computePosition

public static void computePosition(Point center,
                                   double xradius,
                                   double yradius,
                                   double angle,
                                   Point pos)

Computes the position of an entity along the path defined by the supplied parameters assuming that it must finish the path in the specified duration (in millis) and has been traveling the path for the specified number of elapsed milliseconds.