/******************************************************************************* * Copyright (c) 2000, 2012 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.*; import org.eclipse.swt.internal.*; import org.eclipse.swt.internal.cairo.*; /** * 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> * * @see <a href="http://www.eclipse.org/swt/snippets/#path">Path, Pattern snippets</a> * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: GraphicsExample</a> * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> * * @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> * * @noreference This field is not intended to be referenced by clients. */ public long /*int*/ handle; boolean moved, closed = true; /** * 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) { super(device); this.device.checkCairo(); long /*int*/ surface = Cairo.cairo_image_surface_create(Cairo.CAIRO_FORMAT_ARGB32, 1, 1); if (surface == 0) SWT.error(SWT.ERROR_NO_HANDLES); handle = Cairo.cairo_create(surface); Cairo.cairo_surface_destroy(surface); if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES); init(); } /** * Constructs a new Path that is a copy of <code>path</code>. If * <code>flatness</code> is less than or equal to zero, an unflatten * copy of the path is created. Otherwise, it specifies the maximum * error between the path and its flatten copy. Smaller numbers give * better approximation. * <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 * @param path the path to make a copy * @param flatness the flatness value * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li> * <li>ERROR_NULL_ARGUMENT - if the path is null</li> * <li>ERROR_INVALID_ARGUMENT - if the path has been disposed</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() * @since 3.4 */ public Path (Device device, Path path, float flatness) { super(device); if (path == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT); long /*int*/ surface = Cairo.cairo_image_surface_create(Cairo.CAIRO_FORMAT_ARGB32, 1, 1); if (surface == 0) SWT.error(SWT.ERROR_NO_HANDLES); handle = Cairo.cairo_create(surface); Cairo.cairo_surface_destroy(surface); if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES); long /*int*/ copy; flatness = Math.max(0, flatness); if (flatness == 0) { copy = Cairo.cairo_copy_path(path.handle); } else { double tolerance = Cairo.cairo_get_tolerance(path.handle); Cairo.cairo_set_tolerance(path.handle, flatness); copy = Cairo.cairo_copy_path_flat(path.handle); Cairo.cairo_set_tolerance(path.handle, tolerance); } if (copy == 0) { Cairo.cairo_destroy(handle); SWT.error(SWT.ERROR_NO_HANDLES); } Cairo.cairo_append_path(handle, copy); Cairo.cairo_path_destroy(copy); init(); } /** * Constructs a new Path with the specifed PathData. * <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 * @param data the data for the path * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li> * <li>ERROR_NULL_ARGUMENT - if the data is null</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() * @since 3.4 */ public Path (Device device, PathData data) { this(device); if (data == null) SWT.error(SWT.ERROR_NULL_ARGUMENT); init(data); } /** * 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); moved = true; if (width == height) { float angle = -startAngle * (float)Compatibility.PI / 180; if (closed) Cairo.cairo_move_to(handle, (x + width / 2f) + width / 2f * Math.cos(angle), (y + height / 2f) + height / 2f * Math.sin(angle)); if (arcAngle >= 0) { Cairo.cairo_arc_negative(handle, x + width / 2f, y + height / 2f, width / 2f, angle, -(startAngle + arcAngle) * (float)Compatibility.PI / 180); } else { Cairo.cairo_arc(handle, x + width / 2f, y + height / 2f, width / 2f, angle, -(startAngle + arcAngle) * (float)Compatibility.PI / 180); } } else { Cairo.cairo_save(handle); Cairo.cairo_translate(handle, x + width / 2f, y + height / 2f); Cairo.cairo_scale(handle, width / 2f, height / 2f); float angle = -startAngle * (float)Compatibility.PI / 180; if (closed) Cairo.cairo_move_to(handle, Math.cos(angle), Math.sin(angle)); if (arcAngle >= 0) { Cairo.cairo_arc_negative(handle, 0, 0, 1, angle, -(startAngle + arcAngle) * (float)Compatibility.PI / 180); } else { Cairo.cairo_arc(handle, 0, 0, 1, angle, -(startAngle + arcAngle) * (float)Compatibility.PI / 180); } Cairo.cairo_restore(handle); } closed = false; if (Math.abs(arcAngle) >= 360) close(); } /** * 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); moved = false; long /*int*/ copy = Cairo.cairo_copy_path(path.handle); if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES); Cairo.cairo_append_path(handle, copy); Cairo.cairo_path_destroy(copy); closed = path.closed; } /** * 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); moved = false; Cairo.cairo_rectangle(handle, x, y, width, height); closed = true; } /** * 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); moved = false; GC.addCairoString(handle, string, x, y, font); closed = true; } /** * 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); Cairo.cairo_close_path(handle); moved = false; closed = true; } /** * 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); //TODO - see Windows gc.initCairo(); gc.checkGC(GC.LINE_CAP | GC.LINE_JOIN | GC.LINE_STYLE | GC.LINE_WIDTH); boolean result = false; long /*int*/ cairo = gc.data.cairo; long /*int*/ copy = Cairo.cairo_copy_path(handle); if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES); Cairo.cairo_append_path(cairo, copy); Cairo.cairo_path_destroy(copy); if (outline) { result = Cairo.cairo_in_stroke(cairo, x, y) != 0; } else { result = Cairo.cairo_in_fill(cairo, x, y) != 0; } Cairo.cairo_new_path(cairo); return result; } /** * 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); if (!moved) { double[] currentX = new double[1], currentY = new double[1]; Cairo.cairo_get_current_point(handle, currentX, currentY); Cairo.cairo_move_to(handle, currentX[0], currentY[0]); moved = true; } Cairo.cairo_curve_to(handle, cx1, cy1, cx2, cy2, x, y); closed = false; } /** * 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); long /*int*/ copy = Cairo.cairo_copy_path(handle); if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES); cairo_path_t path = new cairo_path_t(); Cairo.memmove(path, copy, cairo_path_t.sizeof); double minX = 0, minY = 0, maxX = 0, maxY = 0; if (path.num_data > 0) { minX = minY = Double.POSITIVE_INFINITY; maxX = maxY = Double.NEGATIVE_INFINITY; int i = 0; double[] points = new double[6]; cairo_path_data_t data = new cairo_path_data_t(); while (i < path.num_data) { long /*int*/ offset = path.data + i * cairo_path_data_t.sizeof; Cairo.memmove(data, offset, cairo_path_data_t.sizeof); switch (data.type) { case Cairo.CAIRO_PATH_MOVE_TO: Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof); minX = Math.min(minX, points[0]); minY = Math.min(minY, points[1]); maxX = Math.max(maxX, points[0]); maxY = Math.max(maxY, points[1]); break; case Cairo.CAIRO_PATH_LINE_TO: Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof); minX = Math.min(minX, points[0]); minY = Math.min(minY, points[1]); maxX = Math.max(maxX, points[0]); maxY = Math.max(maxY, points[1]); break; case Cairo.CAIRO_PATH_CURVE_TO: Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof * 3); minX = Math.min(minX, points[0]); minY = Math.min(minY, points[1]); maxX = Math.max(maxX, points[0]); maxY = Math.max(maxY, points[1]); minX = Math.min(minX, points[2]); minY = Math.min(minY, points[3]); maxX = Math.max(maxX, points[2]); maxY = Math.max(maxY, points[3]); minX = Math.min(minX, points[4]); minY = Math.min(minY, points[5]); maxX = Math.max(maxX, points[4]); maxY = Math.max(maxY, points[5]); break; case Cairo.CAIRO_PATH_CLOSE_PATH: break; } i += data.length; } } bounds[0] = (float)minX; bounds[1] = (float)minY; bounds[2] = (float)(maxX - minX); bounds[3] = (float)(maxY - minY); Cairo.cairo_path_destroy(copy); } /** * 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); double[] x = new double[1], y = new double[1]; Cairo.cairo_get_current_point(handle, x, y); point[0] = (float)x[0]; point[1] = (float)y[0]; } /** * 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); long /*int*/ copy = Cairo.cairo_copy_path(handle); if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES); cairo_path_t path = new cairo_path_t(); Cairo.memmove(path, copy, cairo_path_t.sizeof); byte[] types = new byte[path.num_data]; float[] pts = new float[path.num_data * 6]; int typeIndex = 0, ptsIndex = 0; if (path.num_data > 0) { int i = 0; double[] points = new double[6]; cairo_path_data_t data = new cairo_path_data_t(); while (i < path.num_data) { long /*int*/ offset = path.data + i * cairo_path_data_t.sizeof; Cairo.memmove(data, offset, cairo_path_data_t.sizeof); switch (data.type) { case Cairo.CAIRO_PATH_MOVE_TO: types[typeIndex++] = SWT.PATH_MOVE_TO; Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof); pts[ptsIndex++] = (float)points[0]; pts[ptsIndex++] = (float)points[1]; break; case Cairo.CAIRO_PATH_LINE_TO: types[typeIndex++] = SWT.PATH_LINE_TO; Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof); pts[ptsIndex++] = (float)points[0]; pts[ptsIndex++] = (float)points[1]; break; case Cairo.CAIRO_PATH_CURVE_TO: types[typeIndex++] = SWT.PATH_CUBIC_TO; Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof * 3); pts[ptsIndex++] = (float)points[0]; pts[ptsIndex++] = (float)points[1]; pts[ptsIndex++] = (float)points[2]; pts[ptsIndex++] = (float)points[3]; pts[ptsIndex++] = (float)points[4]; pts[ptsIndex++] = (float)points[5]; break; case Cairo.CAIRO_PATH_CLOSE_PATH: types[typeIndex++] = SWT.PATH_CLOSE; break; } i += data.length; } } if (typeIndex != types.length) { byte[] newTypes = new byte[typeIndex]; System.arraycopy(types, 0, newTypes, 0, typeIndex); types = newTypes; } if (ptsIndex != pts.length) { float[] newPts = new float[ptsIndex]; System.arraycopy(pts, 0, newPts, 0, ptsIndex); pts = newPts; } Cairo.cairo_path_destroy(copy); PathData result = new PathData(); result.types = types; result.points = pts; return result; } /** * 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); if (!moved) { double[] currentX = new double[1], currentY = new double[1]; Cairo.cairo_get_current_point(handle, currentX, currentY); Cairo.cairo_move_to(handle, currentX[0], currentY[0]); moved = true; } Cairo.cairo_line_to(handle, x, y); closed = false; } /** * 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); /* * Bug in Cairo. If cairo_move_to() is not called at the * begining of a subpath, the first cairo_line_to() or * cairo_curve_to() segment do not output anything. The fix * is to detect that the app did not call cairo_move_to() * before those calls and call it explicitly. */ moved = true; Cairo.cairo_move_to(handle, x, y); closed = true; } /** * 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); double[] currentX = new double[1], currentY = new double[1]; Cairo.cairo_get_current_point(handle, currentX, currentY); if (!moved) { Cairo.cairo_move_to(handle, currentX[0], currentY[0]); moved = true; } float x0 = (float)currentX[0]; float y0 = (float)currentY[0]; float cx1 = x0 + 2 * (cx - x0) / 3; float cy1 = y0 + 2 * (cy - y0) / 3; float cx2 = cx1 + (x - x0) / 3; float cy2 = cy1 + (y - y0) / 3; Cairo.cairo_curve_to(handle, cx1, cy1, cx2, cy2, x, y); closed = false; } @Override void destroy() { Cairo.cairo_destroy(handle); handle = 0; } void init(PathData data) { byte[] types = data.types; float[] points = data.points; for (int i = 0, j = 0; i < types.length; i++) { switch (types[i]) { case SWT.PATH_MOVE_TO: moveTo(points[j++], points[j++]); break; case SWT.PATH_LINE_TO: lineTo(points[j++], points[j++]); break; case SWT.PATH_CUBIC_TO: cubicTo(points[j++], points[j++], points[j++], points[j++], points[j++], points[j++]); break; case SWT.PATH_QUAD_TO: quadTo(points[j++], points[j++], points[j++], points[j++]); break; case SWT.PATH_CLOSE: close(); break; default: dispose(); SWT.error(SWT.ERROR_INVALID_ARGUMENT); } } } /** * 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 (except {@link #dispose()}) using the Path. * * @return <code>true</code> when the Path is disposed, and <code>false</code> otherwise */ @Override 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 */ @Override public String toString() { if (isDisposed()) return "Path {*DISPOSED*}"; return "Path {" + handle + "}"; } }