Class FilteredPredicates_2

java.lang.Object

Jcg.geometry.kernel.FilteredPredicates_2

All Implemented Interfaces:

GeometricPredicates_2

public class FilteredPredicates_2
extends Object
implements GeometricPredicates_2

Filtered geometric predicates for plane objects (points, segments, rays)

Remark
Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

Version:

2.0, updated 12/11/2022 (created, december 2022)

Author:

Luca Castelli Aleardi and Steve Oudot (INF562, Ecole Polytechnique)

Field Summary

Fields

Modifier and Type	Field	Description
private static final double	epsilon2
private static final double	epsilon3

Constructor Summary

Constructors

Constructor	Description
FilteredPredicates_2()

Method Summary

Modifier and Type	Method	Description
boolean	collinear(Point_2 a, Point_2 b, Point_2 c)	Returns true if a, b and c lie on a same line Remark Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)
boolean	doIntersect(Segment_2 s, Ray_2 r)	Returns true if segment s and ray r intersect Test is not filtered.
boolean	doIntersect(Segment_2 s, Segment_2 t)	Returns true if segments s and t intersect
boolean	inCircle(Point_2 p, Point_2 a, Point_2 b, Point_2 c)	Tests if point p lies inside the circumcircle of triangle a,b,c
boolean	isClockwise(Point_2 a, Point_2 b, Point_2 c)	Returns true if a, b and c turn in clockwise direction Remark Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)
boolean	isCounterClockwise(Point_2 a, Point_2 b, Point_2 c)	Returns true if a, b and c turn in counter-clockwise direction Remark Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)
boolean	liesOn(Point_2 p, Point_2 a, Point_2 b)	Returns true if point p lies on segment ab
int	orientation(Point_2 a, Point_2 b, Point_2 c)	Returns the orientation of a, b and c

Methods inherited from class java.lang.Object

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

Field Details

epsilon2

private static final double epsilon2

See Also:

• Constant Field Values

epsilon3

private static final double epsilon3

See Also:

• Constant Field Values

Constructor Details

FilteredPredicates_2

public FilteredPredicates_2()

Method Details

orientation

public int orientation(Point_2 a,
 Point_2 b,
 Point_2 c)

Returns the orientation of a, b and c

Specified by:

orientation in interface GeometricPredicates_2

Parameters:

a - ,b,c the 3 points to test

Returns:

1 if sequence (a, b, c) turns in counter-clockwise direction, -1 if it turns in clockwise direction, 0 if the points are collinear Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

isCounterClockwise

public boolean isCounterClockwise(Point_2 a,
 Point_2 b,
 Point_2 c)

Returns true if a, b and c turn in counter-clockwise direction

Remark
Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

Specified by:

isCounterClockwise in interface GeometricPredicates_2

Parameters:

a - ,b,c the 3 points to test

Returns:

true if a, b and c turn in counter-clockwise direction
Warning: the result is false if the three points are collinear

isClockwise

public boolean isClockwise(Point_2 a,
 Point_2 b,
 Point_2 c)

Returns true if a, b and c turn in clockwise direction

Remark
Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

Specified by:

isClockwise in interface GeometricPredicates_2

Parameters:

a - ,b,c the 3 points to test

Returns:

true if a, b and c turn in clockwise direction
Warning: the result is false if the three points are collinear

collinear

public boolean collinear(Point_2 a,
 Point_2 b,
 Point_2 c)

Returns true if a, b and c lie on a same line

Remark
Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

Specified by:

collinear in interface GeometricPredicates_2

Parameters:

a - ,b,c the 3 points to test

Returns:

true if a, b and c are collinear (lie on a same line)

inCircle

public boolean inCircle(Point_2 p,
 Point_2 a,
 Point_2 b,
 Point_2 c)

Tests if point p lies inside the circumcircle of triangle a,b,c

Specified by:

inCircle in interface GeometricPredicates_2

Parameters:

p - point to test

a - ,b,c triangle

Returns:

true/false Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

doIntersect

public boolean doIntersect(Segment_2 s,
 Segment_2 t)

Returns true if segments s and t intersect

Specified by:

doIntersect in interface GeometricPredicates_2

Parameters:

s - ,t the 2 segments

Returns:

true if s,t intersect each other Test is filtered: if precision bound epsilon is reached, then perform computation with infinite precision arithmetic (using the java.util.BigDecimal class)

doIntersect

public boolean doIntersect(Segment_2 s,
 Ray_2 r)

Returns true if segment s and ray r intersect Test is not filtered.

Specified by:

doIntersect in interface GeometricPredicates_2

Parameters:

s - the segment

r - the ray

Returns:

true if s intersects r

liesOn

public boolean liesOn(Point_2 p,
 Point_2 a,
 Point_2 b)

Returns true if point p lies on segment ab

Specified by:

liesOn in interface GeometricPredicates_2

Parameters:

a - ,b,p the 3 points

Returns:

true if ab contains point p