File	Doc	Category	Size	Date	Package
Ellipse2D.java	API Doc	Java SE 5 API	12563	Fri Aug 26 14:56:52 BST 2005	java.awt.geom

Ellipse2D

• java.lang.Object
  • java.awt.geom.RectangularShape

Fields Summary

Constructors Summary
protected Ellipse2D() This is an abstract class that cannot be instantiated directly. Type-specific implementation subclasses are available for instantiation and provide a number of formats for storing the information necessary to satisfy the various accessor methods below. see java.awt.geom.Ellipse2D.Float see java.awt.geom.Ellipse2D.Double

Methods Summary
public boolean	contains(double x, double y) Tests if a specified point is inside the boundary of this Ellipse2D. param x, y the coordinates to test return true if the specified point is contained in this ellipse; false otherwise. // Normalize the coordinates compared to the ellipse // having a center at 0,0 and a radius of 0.5. double ellw = getWidth(); if (ellw <= 0.0) { return false; } double normx = (x - getX()) / ellw - 0.5; double ellh = getHeight(); if (ellh <= 0.0) { return false; } double normy = (y - getY()) / ellh - 0.5; return (normx * normx + normy * normy) < 0.25;
public boolean	contains(double x, double y, double w, double h) Tests if the interior of this Ellipse2D entirely contains the specified rectangular area. param x, y the coordinates of the upper left corner of the specified rectangular area param w the width of the specified rectangular area param h the height of the specified rectangular area return true if this Ellipse2D contains the specified rectangular area; false otherwise. return (contains(x, y) && contains(x + w, y) && contains(x, y + h) && contains(x + w, y + h));
public java.awt.geom.PathIterator	getPathIterator(java.awt.geom.AffineTransform at) Returns an iteration object that defines the boundary of this Ellipse2D. The iterator for this class is multi-threaded safe, which means that this Ellipse2D class guarantees that modifications to the geometry of this Ellipse2D object do not affect any iterations of that geometry that are already in process. param at an optional AffineTransform to be applied to the coordinates as they are returned in the iteration, or null if untransformed coordinates are desired return the PathIterator object that returns the geometry of the outline of this Ellipse2D, one segment at a time. return new EllipseIterator(this, at);
public boolean	intersects(double x, double y, double w, double h) Tests if the interior of this Ellipse2D intersects the interior of a specified rectangular area. param x, y the coordinates of the upper left corner of the specified rectangular area param w the width of the specified rectangular area param h the height of the specified rectangluar area return true if this Ellipse2D contains the specified rectangular area; false otherwise. if (w <= 0.0 || h <= 0.0) { return false; } // Normalize the rectangular coordinates compared to the ellipse // having a center at 0,0 and a radius of 0.5. double ellw = getWidth(); if (ellw <= 0.0) { return false; } double normx0 = (x - getX()) / ellw - 0.5; double normx1 = normx0 + w / ellw; double ellh = getHeight(); if (ellh <= 0.0) { return false; } double normy0 = (y - getY()) / ellh - 0.5; double normy1 = normy0 + h / ellh; // find nearest x (left edge, right edge, 0.0) // find nearest y (top edge, bottom edge, 0.0) // if nearest x,y is inside circle of radius 0.5, then intersects double nearx, neary; if (normx0 > 0.0) { // center to left of X extents nearx = normx0; } else if (normx1 < 0.0) { // center to right of X extents nearx = normx1; } else { nearx = 0.0; } if (normy0 > 0.0) { // center above Y extents neary = normy0; } else if (normy1 < 0.0) { // center below Y extents neary = normy1; } else { neary = 0.0; } return (nearx * nearx + neary * neary) < 0.25;