angle

Documentation

Overview

Package angle define angel calculation function.

Index

• Constants
• func Angle(p0, p1 matrix.Matrix) float64
• func Between(tip1, tail, tip2 matrix.Matrix) float64
• func BetweenOriented(tip1, tail, tip2 matrix.Matrix) float64
• func Diff(ang1, ang2 float64) float64
• func InteriorAngle(p0, p1, p2 matrix.Matrix) float64
• func IsAcute(p0, p1, p2 matrix.Matrix) bool
• func IsObtuse(p0, p1, p2 matrix.Matrix) bool
• func MatrixAngle(p matrix.Matrix) float64
• func Normalize(angle float64) float64
• func NormalizePositive(angle float64) float64
• func Quadrant(p0, p1 matrix.Matrix) (int, error)
• func QuadrantFloat(dx, dy float64) (int, error)
• func ToDegrees(radians float64) float64
• func ToRadians(angleDegrees float64) float64
• func Turn(ang1, ang2 float64) int

Constants

const (
	// PiTimes2 The value of 2*Pi
	PiTimes2 = 2.0 * math.Pi
	// PiOver2 The value of Pi/2
	PiOver2 = math.Pi / 2.0

	// PiOver4 PI_OVER_4The value of Pi/4
	PiOver4 = math.Pi / 4.0

	// None Constant representing no orientation
	None = 0

	// PiDegrees ...
	PiDegrees = 180.0
)

const (
	NE = iota + 1
	NW
	SW
	SE
)

Quadrant four const

Functions

func Angle

func Angle(p0, p1 matrix.Matrix) float64

Angle 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 ].

func Between

func Between(tip1, tail, tip2 matrix.Matrix) float64

Between Returns the smallest angle between two vectors. The computed angle will be in the range [0, Pi).

func BetweenOriented

func BetweenOriented(tip1, tail, tip2 matrix.Matrix) float64

BetweenOriented 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

func Diff

func Diff(ang1, ang2 float64) float64

Diff Computes the 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].

func InteriorAngle

func InteriorAngle(p0, p1, p2 matrix.Matrix) float64

InteriorAngle 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]

func IsAcute

func IsAcute(p0, p1, p2 matrix.Matrix) bool

IsAcute Tests whether the angle between p0-p1-p2 is acute. An angle is acute if it is less than 90 degrees.

func IsObtuse

func IsObtuse(p0, p1, p2 matrix.Matrix) bool

IsObtuse Tests whether the angle between p0-p1-p2 is obtuse. An angle is obtuse if it is greater than 90 degrees.

func MatrixAngle

func MatrixAngle(p matrix.Matrix) float64

MatrixAngle 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 ].

func Normalize

func Normalize(angle float64) float64

Normalize Computes the normalized value of an angle, which is the equivalent angle in the range ( -Pi, Pi ].

func NormalizePositive

func NormalizePositive(angle float64) float64

NormalizePositive Computes the normalized positive value of an angle, which is the

equivalent angle in the range [ 0, 2*Pi ).

func Quadrant

func Quadrant(p0, p1 matrix.Matrix) (int, error)

Quadrant Returns the quadrant of a directed line segment from p0 to p1.

func QuadrantFloat

func QuadrantFloat(dx, dy float64) (int, error)

QuadrantFloat Returns the quadrant of a directed line segment (specified as x and y displacements, which cannot both be 0).

func ToDegrees

func ToDegrees(radians float64) float64

ToDegrees Converts from radians to degrees.

func ToRadians

func ToRadians(angleDegrees float64) float64

ToRadians Converts from degrees to radians.

func Turn

func Turn(ang1, ang2 float64) int

Turn Returns whether an angle must turn clockwise or counterclockwise to overlap another angle.