acm.graphics Class GMath

java.lang.Object acm.graphics.GMath

public class GMath
extends Object

This class defines a variety of static mathematical methods that are useful for the acm.graphics package.

Method Summary
double angle(double x, double y)
Returns the angle in degrees from the origin to the point (xy).
double angle(double x0, double y0, double x1, double y1)
Computes the angle in degrees formed by a line segment from the point (x0y0) and (x1y1).
double cosDegrees(double angle)
Returns the trigonometric cosine of its argument where angle is expressed in degrees.
double distance(double x, double y)
Computes the distance between the origin and the point (xy).
double distance(double x0, double y0, double x1, double y1)
Computes the distance between the points (x0y0) and (x1y1).
int round(double x)
Rounds a double value to the nearest int.
double sinDegrees(double angle)
Returns the trigonometric sine of its argument where angle is expressed in degrees.
double tanDegrees(double angle)
Returns the trigonometric tangent of its argument where angle is expressed in degrees.
Converts an angle from radians to degrees.
Converts an angle from degrees to radians.

Method Detail

public static double angle(double x, double y)

Returns the angle in degrees from the origin to the point (xy). This method is easier to use than atan2 because it specifies the displacements in the usual x/y order and because it takes care of the fact that the Java coordinate system is flipped. The point (0, 0) is arbitrarily defined to be at angle 0.

Usage: double theta = angle(x, y);
Parameters:
 x The x-coordinate of the point y The y-coordinate of the point
Returns: The angle from the origin to the point (xy) measured in degrees counterclockwise from the +x axis

public static double angle(double x0, double y0, double x1, double y1)

Computes the angle in degrees formed by a line segment from the point (x0y0) and (x1y1).

Usage: double theta = angle(x0, y0, x1, y1);
Parameters:
 x0 The x-coordinate of one point y0 The y-coordinate of that point x1 The x-coordinate of the other point y1 The y-coordinate of that point
Returns: The angle formed by the line segment from (x0y0) to (x1y1)

public static double cosDegrees(double angle)

Returns the trigonometric cosine of its argument where angle is expressed in degrees.

Usage: double c = cosDegrees(angle);
Parameter:
 angle An angle measured in degrees
Returns: The trigonometric cosine of the angle

public static double distance(double x, double y)

Computes the distance between the origin and the point (xy).

Usage: double d = distance(x, y);
Parameters:
 x The x-coordinate of the point y The y-coordinate of the point
Returns: The distance from the origin to the point (xy)

public static double distance(double x0, double y0, double x1, double y1)

Computes the distance between the points (x0y0) and (x1y1).

Usage: double d = distance(x0, y0, x1, y1);
Parameters:
 x0 The x-coordinate of one point y0 The y-coordinate of that point x1 The x-coordinate of the other point y1 The y-coordinate of that point
Returns: The distance between the points (x0y0) and (x1y1)

public static int round(double x)

Rounds a double value to the nearest int.

Usage: int n = round(x);
Parameter:
 x A double value
Returns: The nearest int value

public static double sinDegrees(double angle)

Returns the trigonometric sine of its argument where angle is expressed in degrees.

Usage: double s = sinDegrees(angle);
Parameter:
 angle An angle measured in degrees
Returns: The trigonometric sine of the angle

public static double tanDegrees(double angle)

Returns the trigonometric tangent of its argument where angle is expressed in degrees.

Usage: double t = tanDegrees(angle);
Parameter:
 angle An angle measured in degrees
Returns: The trigonometric tangent of the angle

Converts an angle from radians to degrees. This method is defined in the Math class, but was added only in JDK1.2, which is not supported in all browsers.

Parameter:
Returns: The equivalent angle in degrees