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comparison org.eclipse.swt.win32.win32.x86/src/org/eclipse/swt/graphics/Path.d @ 0:6dd524f61e62

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add dwt win and basic java stuff
author Frank Benoit <benoit@tionex.de>
date Mon, 02 Mar 2009 14:44:16 +0100
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1 /*******************************************************************************
2 * Copyright (c) 2000, 2008 IBM Corporation and others.
3 * All rights reserved. This program and the accompanying materials
4 * are made available under the terms of the Eclipse Public License v1.0
5 * which accompanies this distribution, and is available at
6 * http://www.eclipse.org/legal/epl-v10.html
7 *
8 * Contributors:
9 * IBM Corporation - initial API and implementation
10 * Port to the D programming language:
11 * Frank Benoit <benoit@tionex.de>
12 *******************************************************************************/
13 module org.eclipse.swt.graphics.Path;
14
15 import org.eclipse.swt.internal.gdip.Gdip;
16
17 import org.eclipse.swt.SWT;
18 import org.eclipse.swt.SWTError;
19 import org.eclipse.swt.SWTException;
20 import org.eclipse.swt.internal.gdip.Gdip;
21 import org.eclipse.swt.internal.win32.OS;
22
23 import org.eclipse.swt.graphics.Resource;
24 import org.eclipse.swt.graphics.Device;
25 import org.eclipse.swt.graphics.Font;
26 import org.eclipse.swt.graphics.GC;
27 import org.eclipse.swt.graphics.GCData;
28 import org.eclipse.swt.graphics.PathData;
29
30 import java.lang.System;
31 import tango.text.convert.Format;
32 import java.lang.all;
33
34 /**
35 * Instances of this class represent paths through the two-dimensional
36 * coordinate system. Paths do not have to be continuous, and can be
37 * described using lines, rectangles, arcs, cubic or quadratic bezier curves,
38 * glyphs, or other paths.
39 * <p>
40 * Application code must explicitly invoke the <code>Path.dispose()</code>
41 * method to release the operating system resources managed by each instance
42 * when those instances are no longer required.
43 * </p>
44 * <p>
45 * This class requires the operating system's advanced graphics subsystem
46 * which may not be available on some platforms.
47 * </p>
48 *
49 * @see <a href="http://www.eclipse.org/swt/snippets/#path">Path, Pattern snippets</a>
50 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: GraphicsExample</a>
51 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
52 *
53 * @since 3.1
54 */
55 public class Path : Resource {
56
57 alias Resource.init_ init_;
58
59 /**
60 * the OS resource for the Path
61 * (Warning: This field is platform dependent)
62 * <p>
63 * <b>IMPORTANT:</b> This field is <em>not</em> part of the SWT
64 * public API. It is marked public only so that it can be shared
65 * within the packages provided by SWT. It is not available on all
66 * platforms and should never be accessed from application code.
67 * </p>
68 */
69 public Gdip.Path handle;
70
71 Gdip.PointF currentPoint, startPoint;
72
73 /**
74 * Constructs a new empty Path.
75 * <p>
76 * This operation requires the operating system's advanced
77 * graphics subsystem which may not be available on some
78 * platforms.
79 * </p>
80 *
81 * @param device the device on which to allocate the path
82 *
83 * @exception IllegalArgumentException <ul>
84 * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li>
85 * </ul>
86 * @exception SWTException <ul>
87 * <li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li>
88 * </ul>
89 * @exception SWTError <ul>
90 * <li>ERROR_NO_HANDLES if a handle for the path could not be obtained</li>
91 * </ul>
92 *
93 * @see #dispose()
94 */
95 public this (Device device) {
96 super(device);
97 this.device.checkGDIP();
98 handle = Gdip.GraphicsPath_new(Gdip.FillModeAlternate);
99 if (handle is null) SWT.error(SWT.ERROR_NO_HANDLES);
100 init_();
101 }
102
103 /**
104 * Constructs a new Path that is a copy of <code>path</code>. If
105 * <code>flatness</code> is less than or equal to zero, an unflatten
106 * copy of the path is created. Otherwise, it specifies the maximum
107 * error between the path and its flatten copy. Smaller numbers give
108 * better approximation.
109 * <p>
110 * This operation requires the operating system's advanced
111 * graphics subsystem which may not be available on some
112 * platforms.
113 * </p>
114 *
115 * @param device the device on which to allocate the path
116 * @param path the path to make a copy
117 * @param flatness the flatness value
118 *
119 * @exception IllegalArgumentException <ul>
120 * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li>
121 * <li>ERROR_NULL_ARGUMENT - if the path is null</li>
122 * <li>ERROR_INVALID_ARGUMENT - if the path has been disposed</li>
123 * </ul>
124 * @exception SWTException <ul>
125 * <li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li>
126 * </ul>
127 * @exception SWTError <ul>
128 * <li>ERROR_NO_HANDLES if a handle for the path could not be obtained</li>
129 * </ul>
130 *
131 * @see #dispose()
132 * @since 3.4
133 */
134 public this (Device device, Path path, float flatness) {
135 super(device);
136 if (path is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
137 if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
138 flatness = Math.max(0, flatness);
139 handle = Gdip.GraphicsPath_Clone(path.handle);
140 if (flatness !is 0) Gdip.GraphicsPath_Flatten(handle, null, flatness);
141 if (handle is null) SWT.error(SWT.ERROR_NO_HANDLES);
142 init_();
143 }
144
145 /**
146 * Constructs a new Path with the specifed PathData.
147 * <p>
148 * This operation requires the operating system's advanced
149 * graphics subsystem which may not be available on some
150 * platforms.
151 * </p>
152 *
153 * @param device the device on which to allocate the path
154 * @param data the data for the path
155 *
156 * @exception IllegalArgumentException <ul>
157 * <li>ERROR_NULL_ARGUMENT - if the device is null and there is no current device</li>
158 * <li>ERROR_NULL_ARGUMENT - if the data is null</li>
159 * </ul>
160 * @exception SWTException <ul>
161 * <li>ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available</li>
162 * </ul>
163 * @exception SWTError <ul>
164 * <li>ERROR_NO_HANDLES if a handle for the path could not be obtained</li>
165 * </ul>
166 *
167 * @see #dispose()
168 * @since 3.4
169 */
170 public this (Device device, PathData data) {
171 this(device);
172 if (data is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
173 init_(data);
174 }
175
176 /**
177 * Adds to the receiver a circular or elliptical arc that lies within
178 * the specified rectangular area.
179 * <p>
180 * The resulting arc begins at <code>startAngle</code> and extends
181 * for <code>arcAngle</code> degrees.
182 * Angles are interpreted such that 0 degrees is at the 3 o'clock
183 * position. A positive value indicates a counter-clockwise rotation
184 * while a negative value indicates a clockwise rotation.
185 * </p><p>
186 * The center of the arc is the center of the rectangle whose origin
187 * is (<code>x</code>, <code>y</code>) and whose size is specified by the
188 * <code>width</code> and <code>height</code> arguments.
189 * </p><p>
190 * The resulting arc covers an area <code>width + 1</code> pixels wide
191 * by <code>height + 1</code> pixels tall.
192 * </p>
193 *
194 * @param x the x coordinate of the upper-left corner of the arc
195 * @param y the y coordinate of the upper-left corner of the arc
196 * @param width the width of the arc
197 * @param height the height of the arc
198 * @param startAngle the beginning angle
199 * @param arcAngle the angular extent of the arc, relative to the start angle
200 *
201 * @exception SWTException <ul>
202 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
203 * </ul>
204 */
205 public void addArc(float x, float y, float width, float height, float startAngle, float arcAngle) {
206 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
207 if (width < 0) {
208 x = x + width;
209 width = -width;
210 }
211 if (height < 0) {
212 y = y + height;
213 height = -height;
214 }
215 if (width is 0 || height is 0 || arcAngle is 0) return;
216 if (width is height) {
217 Gdip.GraphicsPath_AddArcF(handle, x, y, width, height, -startAngle, -arcAngle);
218 } else {
219 auto path = Gdip.GraphicsPath_new(Gdip.FillModeAlternate);
220 if (path is null) SWT.error(SWT.ERROR_NO_HANDLES);
221 auto matrix = Gdip.Matrix_new(width, 0, 0, height, x, y);
222 if (matrix is null) SWT.error(SWT.ERROR_NO_HANDLES);
223 Gdip.GraphicsPath_AddArc(path, 0, 0, 1, 1, -startAngle, -arcAngle);
224 Gdip.GraphicsPath_Transform(path, matrix);
225 Gdip.GraphicsPath_AddPath(handle, path, true);
226 Gdip.Matrix_delete(matrix);
227 Gdip.GraphicsPath_delete(path);
228 }
229 Gdip.GraphicsPath_GetLastPoint(handle, currentPoint);
230 }
231
232 /**
233 * Adds to the receiver the path described by the parameter.
234 *
235 * @param path the path to add to the receiver
236 *
237 * @exception IllegalArgumentException <ul>
238 * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li>
239 * <li>ERROR_INVALID_ARGUMENT - if the parameter has been disposed</li>
240 * </ul>
241 * @exception SWTException <ul>
242 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
243 * </ul>
244 */
245 public void addPath(Path path) {
246 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
247 if (path is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
248 if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
249 //TODO - expose connect?
250 Gdip.GraphicsPath_AddPath(handle, path.handle, false);
251 currentPoint.X = path.currentPoint.X;
252 currentPoint.Y = path.currentPoint.Y;
253 }
254
255 /**
256 * Adds to the receiver the rectangle specified by x, y, width and height.
257 *
258 * @param x the x coordinate of the rectangle to add
259 * @param y the y coordinate of the rectangle to add
260 * @param width the width of the rectangle to add
261 * @param height the height of the rectangle to add
262 *
263 * @exception SWTException <ul>
264 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
265 * </ul>
266 */
267 public void addRectangle(float x, float y, float width, float height) {
268 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
269 Gdip.RectF rect;
270 rect.X = x;
271 rect.Y = y;
272 rect.Width = width;
273 rect.Height = height;
274 Gdip.GraphicsPath_AddRectangle(handle, rect);
275 currentPoint.X = x;
276 currentPoint.Y = y;
277 }
278
279 /**
280 * Adds to the receiver the pattern of glyphs generated by drawing
281 * the given string using the given font starting at the point (x, y).
282 *
283 * @param string the text to use
284 * @param x the x coordinate of the starting point
285 * @param y the y coordinate of the starting point
286 * @param font the font to use
287 *
288 * @exception IllegalArgumentException <ul>
289 * <li>ERROR_NULL_ARGUMENT - if the font is null</li>
290 * <li>ERROR_INVALID_ARGUMENT - if the font has been disposed</li>
291 * </ul>
292 * @exception SWTException <ul>
293 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
294 * </ul>
295 */
296 public void addString(String string, float x, float y, Font font) {
297 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
298 if (font is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
299 if (font.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
300 wchar[] wstr = StrToWCHARs( string );
301 wchar* buffer = wstr.ptr;
302 int length = wstr.length;
303 auto hDC = device.internal_new_GC(null);
304 auto gdipFont = GC.createGdipFont(hDC, font.handle);
305 Gdip.PointF point;
306 point.X = x - (Gdip.Font_GetSize(gdipFont) / 6);
307 point.Y = y;
308 auto family = Gdip.FontFamily_new();
309 Gdip.Font_GetFamily(gdipFont, family);
310 int style = Gdip.Font_GetStyle(gdipFont);
311 float size = Gdip.Font_GetSize(gdipFont);
312 Gdip.GraphicsPath_AddString(handle, buffer, length, family, style, size, point, null);
313 Gdip.GraphicsPath_GetLastPoint(handle, currentPoint);
314 Gdip.FontFamily_delete(family);
315 Gdip.Font_delete(gdipFont);
316 device.internal_dispose_GC(hDC, null);
317 }
318
319 /**
320 * Closes the current sub path by adding to the receiver a line
321 * from the current point of the path back to the starting point
322 * of the sub path.
323 *
324 * @exception SWTException <ul>
325 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
326 * </ul>
327 */
328 public void close() {
329 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
330 Gdip.GraphicsPath_CloseFigure(handle);
331 /*
332 * Feature in GDI+. CloseFigure() does affect the last
333 * point, so GetLastPoint() does not return the starting
334 * point of the subpath after calling CloseFigure(). The
335 * fix is to remember the subpath starting point and use
336 * it instead.
337 */
338 currentPoint.X = startPoint.X;
339 currentPoint.Y = startPoint.Y;
340 }
341
342 /**
343 * Returns <code>true</code> if the specified point is contained by
344 * the receiver and false otherwise.
345 * <p>
346 * If outline is <code>true</code>, the point (x, y) checked for containment in
347 * the receiver's outline. If outline is <code>false</code>, the point is
348 * checked to see if it is contained within the bounds of the (closed) area
349 * covered by the receiver.
350 *
351 * @param x the x coordinate of the point to test for containment
352 * @param y the y coordinate of the point to test for containment
353 * @param gc the GC to use when testing for containment
354 * @param outline controls whether to check the outline or contained area of the path
355 * @return <code>true</code> if the path contains the point and <code>false</code> otherwise
356 *
357 * @exception IllegalArgumentException <ul>
358 * <li>ERROR_NULL_ARGUMENT - if the gc is null</li>
359 * <li>ERROR_INVALID_ARGUMENT - if the gc has been disposed</li>
360 * </ul>
361 * @exception SWTException <ul>
362 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
363 * </ul>
364 */
365 public bool contains(float x, float y, GC gc, bool outline) {
366 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
367 if (gc is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
368 if (gc.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
369 //TODO - should use GC transformation
370 gc.initGdip();
371 gc.checkGC(GC.LINE_CAP | GC.LINE_JOIN | GC.LINE_STYLE | GC.LINE_WIDTH);
372 int mode = OS.GetPolyFillMode(gc.handle) is OS.WINDING ? Gdip.FillModeWinding : Gdip.FillModeAlternate;
373 Gdip.GraphicsPath_SetFillMode(handle, mode);
374 if (outline) {
375 return Gdip.GraphicsPath_IsOutlineVisible(handle, x, y, gc.data.gdipPen, gc.data.gdipGraphics);
376 } else {
377 return Gdip.GraphicsPath_IsVisible(handle, x, y, gc.data.gdipGraphics);
378 }
379 }
380
381 /**
382 * Adds to the receiver a cubic bezier curve based on the parameters.
383 *
384 * @param cx1 the x coordinate of the first control point of the spline
385 * @param cy1 the y coordinate of the first control of the spline
386 * @param cx2 the x coordinate of the second control of the spline
387 * @param cy2 the y coordinate of the second control of the spline
388 * @param x the x coordinate of the end point of the spline
389 * @param y the y coordinate of the end point of the spline
390 *
391 * @exception SWTException <ul>
392 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
393 * </ul>
394 */
395 public void cubicTo(float cx1, float cy1, float cx2, float cy2, float x, float y) {
396 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
397 Gdip.GraphicsPath_AddBezier(handle, currentPoint.X, currentPoint.Y, cx1, cy1, cx2, cy2, x, y);
398 Gdip.GraphicsPath_GetLastPoint(handle, currentPoint);
399 }
400
401 void destroy() {
402 Gdip.GraphicsPath_delete(handle);
403 handle = null;
404 }
405
406 /**
407 * Replaces the first four elements in the parameter with values that
408 * describe the smallest rectangle that will completely contain the
409 * receiver (i.e. the bounding box).
410 *
411 * @param bounds the array to hold the result
412 *
413 * @exception IllegalArgumentException <ul>
414 * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li>
415 * <li>ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the bounding box</li>
416 * </ul>
417 * @exception SWTException <ul>
418 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
419 * </ul>
420 */
421 public void getBounds(float[] bounds) {
422 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
423 if (bounds is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
424 if (bounds.length < 4) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
425 Gdip.RectF rect;
426 Gdip.GraphicsPath_GetBounds(handle, rect, null, null);
427 bounds[0] = rect.X;
428 bounds[1] = rect.Y;
429 bounds[2] = rect.Width;
430 bounds[3] = rect.Height;
431 }
432
433 /**
434 * Replaces the first two elements in the parameter with values that
435 * describe the current point of the path.
436 *
437 * @param point the array to hold the result
438 *
439 * @exception IllegalArgumentException <ul>
440 * <li>ERROR_NULL_ARGUMENT - if the parameter is null</li>
441 * <li>ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the end point</li>
442 * </ul>
443 * @exception SWTException <ul>
444 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
445 * </ul>
446 */
447 public void getCurrentPoint(float[] point) {
448 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
449 if (point is null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
450 if (point.length < 2) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
451 point[0] = currentPoint.X;
452 point[1] = currentPoint.Y;
453 }
454
455 /**
456 * Returns a device independent representation of the receiver.
457 *
458 * @return the PathData for the receiver
459 *
460 * @exception SWTException <ul>
461 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
462 * </ul>
463 *
464 * @see PathData
465 */
466 public PathData getPathData() {
467 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
468 int count = Gdip.GraphicsPath_GetPointCount(handle);
469 byte[] gdipTypes = new byte[count];
470 float[] points = new float[count * 2];
471 Gdip.GraphicsPath_GetPathTypes(handle, gdipTypes.ptr, count);
472 Gdip.GraphicsPath_GetPathPoints(handle, cast(Gdip.PointF*)points.ptr, count);
473 byte[] types = new byte[count * 2];
474 int index = 0, typesIndex = 0;
475 while (index < count) {
476 byte type = gdipTypes[index];
477 bool close = false;
478 switch (type & Gdip.PathPointTypePathTypeMask) {
479 case Gdip.PathPointTypeStart:
480 types[typesIndex++] = SWT.PATH_MOVE_TO;
481 close = (type & Gdip.PathPointTypeCloseSubpath) !is 0;
482 index += 1;
483 break;
484 case Gdip.PathPointTypeLine:
485 types[typesIndex++] = SWT.PATH_LINE_TO;
486 close = (type & Gdip.PathPointTypeCloseSubpath) !is 0;
487 index += 1;
488 break;
489 case Gdip.PathPointTypeBezier:
490 types[typesIndex++] = SWT.PATH_CUBIC_TO;
491 close = (gdipTypes[index + 2] & Gdip.PathPointTypeCloseSubpath) !is 0;
492 index += 3;
493 break;
494 default:
495 index++;
496 }
497 if (close) {
498 types[typesIndex++] = SWT.PATH_CLOSE;
499 }
500 }
501 if (typesIndex !is types.length) {
502 byte[] newTypes = new byte[typesIndex];
503 System.arraycopy(types, 0, newTypes, 0, typesIndex);
504 types = newTypes;
505 }
506 PathData result = new PathData();
507 result.types = types;
508 result.points = points;
509 return result;
510 }
511
512 /**
513 * Adds to the receiver a line from the current point to
514 * the point specified by (x, y).
515 *
516 * @param x the x coordinate of the end of the line to add
517 * @param y the y coordinate of the end of the line to add
518 *
519 * @exception SWTException <ul>
520 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
521 * </ul>
522 */
523 public void lineTo(float x, float y) {
524 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
525 Gdip.GraphicsPath_AddLine(handle, currentPoint.X, currentPoint.Y, x, y);
526 Gdip.GraphicsPath_GetLastPoint(handle, currentPoint);
527 }
528
529 void init_(PathData data) {
530 byte[] types = data.types;
531 float[] points = data.points;
532 for (int i = 0, j = 0; i < types.length; i++) {
533 switch (types[i]) {
534 case SWT.PATH_MOVE_TO:
535 moveTo(points[j++], points[j++]);
536 break;
537 case SWT.PATH_LINE_TO:
538 lineTo(points[j++], points[j++]);
539 break;
540 case SWT.PATH_CUBIC_TO:
541 cubicTo(points[j++], points[j++], points[j++], points[j++], points[j++], points[j++]);
542 break;
543 case SWT.PATH_QUAD_TO:
544 quadTo(points[j++], points[j++], points[j++], points[j++]);
545 break;
546 case SWT.PATH_CLOSE:
547 close();
548 break;
549 default:
550 dispose();
551 SWT.error(SWT.ERROR_INVALID_ARGUMENT);
552 }
553 }
554 }
555
556 /**
557 * Returns <code>true</code> if the Path has been disposed,
558 * and <code>false</code> otherwise.
559 * <p>
560 * This method gets the dispose state for the Path.
561 * When a Path has been disposed, it is an error to
562 * invoke any other method using the Path.
563 *
564 * @return <code>true</code> when the Path is disposed, and <code>false</code> otherwise
565 */
566 override public bool isDisposed() {
567 return handle is null;
568 }
569
570 /**
571 * Sets the current point of the receiver to the point
572 * specified by (x, y). Note that this starts a new
573 * sub path.
574 *
575 * @param x the x coordinate of the new end point
576 * @param y the y coordinate of the new end point
577 *
578 * @exception SWTException <ul>
579 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
580 * </ul>
581 */
582 public void moveTo(float x, float y) {
583 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
584 Gdip.GraphicsPath_StartFigure(handle);
585 currentPoint.X = startPoint.X = x;
586 currentPoint.Y = startPoint.Y = y;
587 }
588
589 /**
590 * Adds to the receiver a quadratic curve based on the parameters.
591 *
592 * @param cx the x coordinate of the control point of the spline
593 * @param cy the y coordinate of the control point of the spline
594 * @param x the x coordinate of the end point of the spline
595 * @param y the y coordinate of the end point of the spline
596 *
597 * @exception SWTException <ul>
598 * <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li>
599 * </ul>
600 */
601 public void quadTo(float cx, float cy, float x, float y) {
602 if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
603 float cx1 = currentPoint.X + 2 * (cx - currentPoint.X) / 3;
604 float cy1 = currentPoint.Y + 2 * (cy - currentPoint.Y) / 3;
605 float cx2 = cx1 + (x - currentPoint.X) / 3;
606 float cy2 = cy1 + (y - currentPoint.Y) / 3;
607 Gdip.GraphicsPath_AddBezier(handle, currentPoint.X, currentPoint.Y, cx1, cy1, cx2, cy2, x, y);
608 Gdip.GraphicsPath_GetLastPoint(handle, currentPoint);
609 }
610
611 /**
612 * Returns a string containing a concise, human-readable
613 * description of the receiver.
614 *
615 * @return a string representation of the receiver
616 */
617 override public String toString() {
618 if (isDisposed()) return "Path {*DISPOSED*}";
619 return Format( "Path {{{}}", handle );
620 }
621
622 }