Module org.dyn4j

Package org.dyn4j.geometry

Class RobustGeometry

Object

RobustGeometry

public final class RobustGeometry
extends Object

This class provides geometric routines that have guarantees about some properties of their floating point results and operations.

Since:

3.4.0

Version:

3.4.0

Author:

Manolis Tsamis

Constructor Summary

Constructors

Constructor	Description
RobustGeometry()

Method Summary

Modifier and Type	Method	Description
static AdaptiveDecimal	cross(double ax, double ay, double bx, double by)	Performs cross product on four primitives and also allocates a new AdaptiveDecimal with the appropriate capacity to store the result.
static AdaptiveDecimal	cross(double ax, double ay, double bx, double by, AdaptiveDecimal result)	Performs the cross product of two vectors a, b, that is ax * by - ay * bx but with extended precision and stores the 4 component result in the given AdaptiveDecimal result.
static double	getLocation(Vector2 point, Vector2 linePoint1, Vector2 linePoint2)	Robust side-of-line test.

Methods inherited from class Object

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

Constructor Detail

RobustGeometry

public RobustGeometry()

Method Detail

cross

public static AdaptiveDecimal cross(double ax,
                                    double ay,
                                    double bx,
                                    double by)

Performs cross product on four primitives and also allocates a new AdaptiveDecimal with the appropriate capacity to store the result.

Parameters:

ax - The x value of the vector a

ay - The y value of the vector a

bx - The x value of the vector b

by - The y value of the vector b

Returns:

The result

See Also:

cross(double, double, double, double, AdaptiveDecimal)

cross

public static AdaptiveDecimal cross(double ax,
                                    double ay,
                                    double bx,
                                    double by,
                                    AdaptiveDecimal result)

Performs the cross product of two vectors a, b, that is ax * by - ay * bx but with extended precision and stores the 4 component result in the given AdaptiveDecimal result. In the same way as with AdaptiveDecimal.sum(AdaptiveDecimal, AdaptiveDecimal) if result is null a new one is allocated, otherwise the existing is cleared and used.

Parameters:

ax - The x value of the vector a

ay - The y value of the vector a

bx - The x value of the vector b

by - The y value of the vector b

result - The AdaptiveDecimal in which the cross product is stored

Returns:

The result

getLocation

public static double getLocation(Vector2 point,
                                 Vector2 linePoint1,
                                 Vector2 linePoint2)

Robust side-of-line test. Computes the same value with Segment.getLocation(Vector2, Vector2, Vector2) but with enough precision so the sign of the result is correct for any Vector2s pa, pb, pc. This implementation uses more precision as-needed only for the hardest cases. For the majority of inputs this will be only slightly slower than the corresponding call to Segment.getLocation(Vector2, Vector2, Vector2) but in the hard cases can be 5-25 times slower.

Parameters:

point - the point

linePoint1 - the first point of the line

linePoint2 - the second point of the line

Returns:

double

See Also:

Segment.getLocation(Vector2, Vector2, Vector2)