| /******************************************************************************* |
| * Copyright (c) 2000, 2007 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.graphics; |
| |
| import org.eclipse.swt.*; |
| |
| /** |
| * Instances of this class represent paths through the two-dimensional |
| * coordinate system. Paths do not have to be continuous, and can be |
| * described using lines, rectangles, arcs, cubic or quadratic bezier curves, |
| * glyphs, or other paths. |
| * <p> |
| * Application code must explicitly invoke the <code>Path.dispose()</code> |
| * method to release the operating system resources managed by each instance |
| * when those instances are no longer required. |
| * </p> |
| * <p> |
| * This class requires the operating system's advanced graphics subsystem |
| * which may not be available on some platforms. |
| * </p> |
| * |
| * @since 3.1 |
| */ |
| public class Path extends Resource { |
| |
| /** |
| * the OS resource for the Path |
| * (Warning: This field is platform dependent) |
| * <p> |
| * <b>IMPORTANT:</b> This field is <em>not</em> part of the SWT |
| * public API. It is marked public only so that it can be shared |
| * within the packages provided by SWT. It is not available on all |
| * platforms and should never be accessed from application code. |
| * </p> |
| */ |
| public int handle; |
| |
| /** |
| * Constructs a new empty Path. |
| * <p> |
| * This operation requires the operating system's advanced |
| * graphics subsystem which may not be available on some |
| * platforms. |
| * </p> |
| * |
| * @param device the device on which to allocate the path |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li> |
| * </ul> |
| * @exception SWTError <ul> |
| * <li>ERROR_NO_HANDLES if a handle for the path could not be obtained</li> |
| * </ul> |
| * |
| * @see #dispose() |
| */ |
| public Path (Device device) { |
| if (device == null) device = Device.getDevice(); |
| if (device == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| this.device = device; |
| SWT.error(SWT.ERROR_NO_GRAPHICS_LIBRARY); |
| if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES); |
| if (device.tracking) device.new_Object(this); |
| } |
| |
| /** |
| * Adds to the receiver a circular or elliptical arc that lies within |
| * the specified rectangular area. |
| * <p> |
| * The resulting arc begins at <code>startAngle</code> and extends |
| * for <code>arcAngle</code> degrees. |
| * Angles are interpreted such that 0 degrees is at the 3 o'clock |
| * position. A positive value indicates a counter-clockwise rotation |
| * while a negative value indicates a clockwise rotation. |
| * </p><p> |
| * The center of the arc is the center of the rectangle whose origin |
| * is (<code>x</code>, <code>y</code>) and whose size is specified by the |
| * <code>width</code> and <code>height</code> arguments. |
| * </p><p> |
| * The resulting arc covers an area <code>width + 1</code> pixels wide |
| * by <code>height + 1</code> pixels tall. |
| * </p> |
| * |
| * @param x the x coordinate of the upper-left corner of the arc |
| * @param y the y coordinate of the upper-left corner of the arc |
| * @param width the width of the arc |
| * @param height the height of the arc |
| * @param startAngle the beginning angle |
| * @param arcAngle the angular extent of the arc, relative to the start angle |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void addArc(float x, float y, float width, float height, float startAngle, float arcAngle) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Adds to the receiver the path described by the parameter. |
| * |
| * @param path the path to add to the receiver |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the parameter has been disposed</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void addPath(Path path) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| if (path == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT); |
| } |
| |
| /** |
| * Adds to the receiver the rectangle specified by x, y, width and height. |
| * |
| * @param x the x coordinate of the rectangle to add |
| * @param y the y coordinate of the rectangle to add |
| * @param width the width of the rectangle to add |
| * @param height the height of the rectangle to add |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void addRectangle(float x, float y, float width, float height) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Adds to the receiver the pattern of glyphs generated by drawing |
| * the given string using the given font starting at the point (x, y). |
| * |
| * @param string the text to use |
| * @param x the x coordinate of the starting point |
| * @param y the y coordinate of the starting point |
| * @param font the font to use |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the font is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the font has been disposed</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void addString(String string, float x, float y, Font font) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| if (font == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| if (font.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT); |
| } |
| |
| /** |
| * Returns <code>true</code> if the specified point is contained by |
| * the receiver and false otherwise. |
| * <p> |
| * If outline is <code>true</code>, the point (x, y) checked for containment in |
| * the receiver's outline. If outline is <code>false</code>, the point is |
| * checked to see if it is contained within the bounds of the (closed) area |
| * covered by the receiver. |
| * |
| * @param x the x coordinate of the point to test for containment |
| * @param y the y coordinate of the point to test for containment |
| * @param gc the GC to use when testing for containment |
| * @param outline controls whether to check the outline or contained area of the path |
| * @return <code>true</code> if the path contains the point and <code>false</code> otherwise |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the gc is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the gc has been disposed</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public boolean contains(float x, float y, GC gc, boolean outline) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| if (gc == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| if (gc.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT); |
| return false; |
| } |
| |
| /** |
| * Closes the current sub path by adding to the receiver a line |
| * from the current point of the path back to the starting point |
| * of the sub path. |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void close() { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Adds to the receiver a cubic bezier curve based on the parameters. |
| * |
| * @param cx1 the x coordinate of the first control point of the spline |
| * @param cy1 the y coordinate of the first control of the spline |
| * @param cx2 the x coordinate of the second control of the spline |
| * @param cy2 the y coordinate of the second control of the spline |
| * @param x the x coordinate of the end point of the spline |
| * @param y the y coordinate of the end point of the spline |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void cubicTo(float cx1, float cy1, float cx2, float cy2, float x, float y) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Replaces the first four elements in the parameter with values that |
| * describe the smallest rectangle that will completely contain the |
| * receiver (i.e. the bounding box). |
| * |
| * @param bounds the array to hold the result |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the bounding box</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void getBounds(float[] bounds) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| if (bounds == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| if (bounds.length < 4) SWT.error(SWT.ERROR_INVALID_ARGUMENT); |
| } |
| |
| /** |
| * Replaces the first two elements in the parameter with values that |
| * describe the current point of the path. |
| * |
| * @param point the array to hold the result |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the end point</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void getCurrentPoint(float[] point) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| if (point == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); |
| if (point.length < 2) SWT.error(SWT.ERROR_INVALID_ARGUMENT); |
| } |
| |
| /** |
| * Returns a device independent representation of the receiver. |
| * |
| * @return the PathData for the receiver |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| * |
| * @see PathData |
| */ |
| public PathData getPathData() { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| return null; |
| } |
| |
| /** |
| * Adds to the receiver a line from the current point to |
| * the point specified by (x, y). |
| * |
| * @param x the x coordinate of the end of the line to add |
| * @param y the y coordinate of the end of the line to add |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void lineTo(float x, float y) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Sets the current point of the receiver to the point |
| * specified by (x, y). Note that this starts a new |
| * sub path. |
| * |
| * @param x the x coordinate of the new end point |
| * @param y the y coordinate of the new end point |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void moveTo(float x, float y) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Adds to the receiver a quadratic curve based on the parameters. |
| * |
| * @param cx the x coordinate of the control point of the spline |
| * @param cy the y coordinate of the control point of the spline |
| * @param x the x coordinate of the end point of the spline |
| * @param y the y coordinate of the end point of the spline |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> |
| * </ul> |
| */ |
| public void quadTo(float cx, float cy, float x, float y) { |
| if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED); |
| } |
| |
| /** |
| * Disposes of the operating system resources associated with |
| * the Path. Applications must dispose of all Paths that |
| * they allocate. |
| */ |
| public void dispose() { |
| if (handle == 0) return; |
| handle = 0; |
| if (device.tracking) device.dispose_Object(this); |
| device = null; |
| } |
| |
| /** |
| * Returns <code>true</code> if the Path has been disposed, |
| * and <code>false</code> otherwise. |
| * <p> |
| * This method gets the dispose state for the Path. |
| * When a Path has been disposed, it is an error to |
| * invoke any other method using the Path. |
| * |
| * @return <code>true</code> when the Path is disposed, and <code>false</code> otherwise |
| */ |
| public boolean isDisposed() { |
| return handle == 0; |
| } |
| |
| /** |
| * Returns a string containing a concise, human-readable |
| * description of the receiver. |
| * |
| * @return a string representation of the receiver |
| */ |
| public String toString() { |
| if (isDisposed()) return "Path {*DISPOSED*}"; |
| return "Path {" + handle + "}"; |
| } |
| |
| } |