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toDegrees(double): double
toRadians(double): double
angle(Coordinate, Coordinate): double
angle(Coordinate): double
isAcute(Coordinate, Coordinate, Coordinate): boolean
isObtuse(Coordinate, Coordinate, Coordinate): boolean
angleBetween(Coordinate, Coordinate, Coordinate): double
angleBetweenOriented(Coordinate, Coordinate, Coordinate): double
interiorAngle(Coordinate, Coordinate, Coordinate): double
getTurn(double, double): int
normalize(double): double
normalizePositive(double): double
diff(double, double): double
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Source Classic

Class Angle

Hierarchy: Object , Angle
public class Angle
Utility functions for working with angles. Unless otherwise noted, methods in this class express angles in radians.
public static double toDegrees(double radians)
Converts from radians to degrees.
Parameters:
radians - radians an angle in radians
Returns:
the angle in degrees
public static double toRadians(double angleDegrees)
Converts from degrees to radians.
Parameters:
angleDegrees - angleDegrees an angle in degrees
Returns:
the angle in radians
public static double angle(Coordinate p0, Coordinate p1)
Returns the angle of the vector from p0 to p1, relative to the positive X-axis. The angle is normalized to be in the range [ -Pi, Pi ].
Parameters:
p0 - p0 the initial point of the vector
p1 - p1 the terminal point of the vector
Returns:
the normalized angle (in radians) that p0-p1 makes with the positive x-axis.
public static double angle(Coordinate p)
Returns the angle of the vector from (0,0) to p, relative to the positive X-axis. The angle is normalized to be in the range ( -Pi, Pi ].
Parameters:
p - p the terminal point of the vector
Returns:
the normalized angle (in radians) that p makes with the positive x-axis.
public static boolean isAcute(Coordinate p0, Coordinate p1, Coordinate p2)
Tests whether the angle between p0-p1-p2 is acute. An angle is acute if it is less than 90 degrees.

Note: this implementation is not precise (deterministic) for angles very close to 90 degrees.

Parameters:
p0 - p0 an endpoint of the angle
p1 - p1 the base of the angle
p2 - p2 the other endpoint of the angle
Returns:
true if the angle is acute
public static boolean isObtuse(Coordinate p0, Coordinate p1, Coordinate p2)
Tests whether the angle between p0-p1-p2 is obtuse. An angle is obtuse if it is greater than 90 degrees.

Note: this implementation is not precise (deterministic) for angles very close to 90 degrees.

Parameters:
p0 - p0 an endpoint of the angle
p1 - p1 the base of the angle
p2 - p2 the other endpoint of the angle
Returns:
true if the angle is obtuse
public static double angleBetween(Coordinate tip1, Coordinate tail, Coordinate tip2)
Returns the unoriented smallest angle between two vectors. The computed angle will be in the range [0, Pi).
Parameters:
tip1 - tip1 the tip of one vector
tail - tail the tail of each vector
tip2 - tip2 the tip of the other vector
Returns:
the angle between tail-tip1 and tail-tip2
public static double angleBetweenOriented(Coordinate tip1, Coordinate tail, Coordinate tip2)
Returns the oriented smallest angle between two vectors. The computed angle will be in the range (-Pi, Pi]. A positive result corresponds to a counterclockwise (CCW) rotation from v1 to v2; a negative result corresponds to a clockwise (CW) rotation; a zero result corresponds to no rotation.
Parameters:
tip1 - tip1 the tip of v1
tail - tail the tail of each vector
tip2 - tip2 the tip of v2
Returns:
the angle between v1 and v2, relative to v1
public static double interiorAngle(Coordinate p0, Coordinate p1, Coordinate p2)
Computes the interior angle between two segments of a ring. The ring is assumed to be oriented in a clockwise direction. The computed angle will be in the range [0, 2Pi]
Parameters:
p0 - p0 a point of the ring
p1 - p1 the next point of the ring
p2 - p2 the next point of the ring
Returns:
the interior angle based at p1
public static int getTurn(double ang1, double ang2)
Returns whether an angle must turn clockwise or counterclockwise to overlap another angle.
Parameters:
ang1 - ang1 an angle (in radians)
ang2 - ang2 an angle (in radians)
Returns:
whether a1 must turn CLOCKWISE, COUNTERCLOCKWISE or NONE to overlap a2.
public static double normalize(double angle)
Computes the normalized value of an angle, which is the equivalent angle in the range ( -Pi, Pi ].
Parameters:
angle - angle the angle to normalize
Returns:
an equivalent angle in the range (-Pi, Pi]
public static double normalizePositive(double angle)
Computes the normalized positive value of an angle, which is the equivalent angle in the range [ 0, 2*Pi ). E.g.:
  • normalizePositive(0.0) = 0.0
  • normalizePositive(-PI) = PI
  • normalizePositive(-2PI) = 0.0
  • normalizePositive(-3PI) = PI
  • normalizePositive(-4PI) = 0
  • normalizePositive(PI) = PI
  • normalizePositive(2PI) = 0.0
  • normalizePositive(3PI) = PI
  • normalizePositive(4PI) = 0.0
Parameters:
angle - angle the angle to normalize, in radians
Returns:
an equivalent positive angle
public static double diff(double ang1, double ang2)
Computes the unoriented smallest difference between two angles. The angles are assumed to be normalized to the range [-Pi, Pi]. The result will be in the range [0, Pi].
Parameters:
ang1 - ang1 the angle of one vector (in [-Pi, Pi] )
ang2 - ang2 the angle of the other vector (in range [-Pi, Pi] )
Returns:
the angle (in radians) between the two vectors (in range [0, Pi] )