1 /*
2 * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.java2d.pipe;
27
28 import java.awt.Shape;
29 import java.awt.BasicStroke;
30 import java.awt.geom.PathIterator;
31 import java.awt.geom.AffineTransform;
32
33 import java.security.PrivilegedAction;
34 import java.security.AccessController;
35 import sun.security.action.GetPropertyAction;
36
37 import sun.awt.geom.PathConsumer2D;
38
39 /**
40 * This class abstracts a number of features for which the Java 2D
41 * implementation relies on proprietary licensed software libraries.
42 * Access to those features is now achieved by retrieving the singleton
43 * instance of this class and calling the appropriate methods on it.
44 * The 3 primary features abstracted here include:
45 * <dl>
46 * <dt>Shape createStrokedShape(Shape, [BasicStroke attributes]);
47 * <dd>This method implements the functionality of the method of the
48 * same name on the {@link BasicStroke} class.
49 * <dt>void strokeTo(Shape, [rendering parameters], PathConsumer2D);
50 * <dd>This method performs widening of the source path on the fly
51 * and sends the results to the given {@link PathConsumer2D} object.
52 * This procedure avoids having to create an intermediate Shape
53 * object to hold the results of the {@code createStrokedShape} method.
54 * The main user of this method is the Java 2D non-antialiasing renderer.
55 * <dt>AATileGenerator getAATileGenerator(Shape, [rendering parameters]);
56 * <dd>This method returns an object which can iterate over the
57 * specified bounding box and produce tiles of coverage values for
58 * antialiased rendering. The details of the operation of the
59 * {@link AATileGenerator} object are explained in its class comments.
60 * </dl>
61 * Additionally, the following informational method supplies important
62 * data about the implementation.
63 * <dl>
64 * <dt>float getMinimumAAPenSize()
65 * <dd>This method provides information on how small the BasicStroke
66 * line width can get before dropouts occur. Rendering with a BasicStroke
67 * is defined to never allow the line to have breaks, gaps, or dropouts
68 * even if the width is set to 0.0f, so this information allows the
69 * {@link SunGraphics2D} class to detect the "thin line" case and set
70 * the rendering attributes accordingly.
71 * </dl>
72 * At startup the runtime will load a single instance of this class.
73 * It searches the classpath for a registered provider of this API
74 * and returns either the last one it finds, or the instance whose
75 * class name matches the value supplied in the System property
76 * {@code sun.java2d.renderer}.
77 * Additionally, a runtime System property flag can be set to trace
78 * all calls to methods on the {@code RenderingEngine} in use by
79 * setting the sun.java2d.renderer.trace property to any non-null value.
80 * <p>
81 * Parts of the system that need to use any of the above features should
82 * call {@code RenderingEngine.getInstance()} to obtain the properly
83 * registered (and possibly trace-enabled) version of the RenderingEngine.
84 */
85 public abstract class RenderingEngine {
86 private static RenderingEngine reImpl;
87
88 /**
89 * Returns an instance of {@code RenderingEngine} as determined
90 * by the installation environment and runtime flags.
91 * <p>
92 * A specific instance of the {@code RenderingEngine} can be
93 * chosen by specifying the runtime flag:
94 * <pre>
95 * java -Dsun.java2d.renderer=<classname>
96 * </pre>
97 *
98 * If no specific {@code RenderingEngine} is specified on the command
99 * or Ductus renderer is specified, it will first attempt loading the
100 * sun.dc.DuctusRenderingEngine class using Class.forName, if that
101 * is not found, then it will look for Pisces.
102 * <p>
103 * Runtime tracing of the actions of the {@code RenderingEngine}
104 * can be enabled by specifying the runtime flag:
105 * <pre>
106 * java -Dsun.java2d.renderer.trace=<any string>
107 * </pre>
108 * @return an instance of {@code RenderingEngine}
109 * @since 1.7
110 */
111 public static synchronized RenderingEngine getInstance() {
112 if (reImpl != null) {
113 return reImpl;
114 }
115
116 /* Look first for ductus or an app-override renderer,
117 * if not specified or present, then look for pisces.
118 */
119 final String ductusREClass = "sun.dc.DuctusRenderingEngine";
120 final String piscesREClass = "sun.java2d.pisces.PiscesRenderingEngine";
121 GetPropertyAction gpa =
122 new GetPropertyAction("sun.java2d.renderer", ductusREClass);
123 String reClass = AccessController.doPrivileged(gpa);
124 try {
125 Class<?> cls = Class.forName(reClass);
126 reImpl = (RenderingEngine) cls.newInstance();
127 } catch (ReflectiveOperationException ignored0) {
128 try {
129 Class<?> cls = Class.forName(piscesREClass);
130 reImpl = (RenderingEngine) cls.newInstance();
131 } catch (ReflectiveOperationException ignored1) {
132 }
133 }
134
135 if (reImpl == null) {
136 throw new InternalError("No RenderingEngine module found");
137 }
138
139 gpa = new GetPropertyAction("sun.java2d.renderer.trace");
140 String reTrace = AccessController.doPrivileged(gpa);
141 if (reTrace != null) {
142 reImpl = new Tracer(reImpl);
143 }
144
145 return reImpl;
146 }
147
148 /**
149 * Create a widened path as specified by the parameters.
150 * <p>
151 * The specified {@code src} {@link Shape} is widened according
152 * to the specified attribute parameters as per the
153 * {@link BasicStroke} specification.
154 *
155 * @param src the source path to be widened
156 * @param width the width of the widened path as per {@code BasicStroke}
157 * @param caps the end cap decorations as per {@code BasicStroke}
158 * @param join the segment join decorations as per {@code BasicStroke}
159 * @param miterlimit the miter limit as per {@code BasicStroke}
160 * @param dashes the dash length array as per {@code BasicStroke}
161 * @param dashphase the initial dash phase as per {@code BasicStroke}
162 * @return the widened path stored in a new {@code Shape} object
163 * @since 1.7
164 */
165 public abstract Shape createStrokedShape(Shape src,
166 float width,
167 int caps,
168 int join,
169 float miterlimit,
170 float dashes[],
171 float dashphase);
172
173 /**
174 * Sends the geometry for a widened path as specified by the parameters
175 * to the specified consumer.
176 * <p>
177 * The specified {@code src} {@link Shape} is widened according
178 * to the parameters specified by the {@link BasicStroke} object.
179 * Adjustments are made to the path as appropriate for the
180 * {@link VALUE_STROKE_NORMALIZE} hint if the {@code normalize}
181 * boolean parameter is true.
182 * Adjustments are made to the path as appropriate for the
183 * {@link VALUE_ANTIALIAS_ON} hint if the {@code antialias}
184 * boolean parameter is true.
185 * <p>
186 * The geometry of the widened path is forwarded to the indicated
187 * {@link PathConsumer2D} object as it is calculated.
188 *
189 * @param src the source path to be widened
190 * @param bs the {@code BasicSroke} object specifying the
191 * decorations to be applied to the widened path
192 * @param normalize indicates whether stroke normalization should
193 * be applied
194 * @param antialias indicates whether or not adjustments appropriate
195 * to antialiased rendering should be applied
196 * @param consumer the {@code PathConsumer2D} instance to forward
197 * the widened geometry to
198 * @since 1.7
199 */
200 public abstract void strokeTo(Shape src,
201 AffineTransform at,
202 BasicStroke bs,
203 boolean thin,
204 boolean normalize,
205 boolean antialias,
206 PathConsumer2D consumer);
207
208 /**
209 * Construct an antialiased tile generator for the given shape with
210 * the given rendering attributes and store the bounds of the tile
211 * iteration in the bbox parameter.
212 * The {@code at} parameter specifies a transform that should affect
213 * both the shape and the {@code BasicStroke} attributes.
214 * The {@code clip} parameter specifies the current clip in effect
215 * in device coordinates and can be used to prune the data for the
216 * operation, but the renderer is not required to perform any
217 * clipping.
218 * If the {@code BasicStroke} parameter is null then the shape
219 * should be filled as is, otherwise the attributes of the
220 * {@code BasicStroke} should be used to specify a draw operation.
221 * The {@code thin} parameter indicates whether or not the
222 * transformed {@code BasicStroke} represents coordinates smaller
223 * than the minimum resolution of the antialiasing rasterizer as
224 * specified by the {@code getMinimumAAPenWidth()} method.
225 * <p>
226 * Upon returning, this method will fill the {@code bbox} parameter
227 * with 4 values indicating the bounds of the iteration of the
228 * tile generator.
229 * The iteration order of the tiles will be as specified by the
230 * pseudo-code:
231 * <pre>
232 * for (y = bbox[1]; y < bbox[3]; y += tileheight) {
233 * for (x = bbox[0]; x < bbox[2]; x += tilewidth) {
234 * }
235 * }
236 * </pre>
237 * If there is no output to be rendered, this method may return
238 * null.
239 *
240 * @param s the shape to be rendered (fill or draw)
241 * @param at the transform to be applied to the shape and the
242 * stroke attributes
243 * @param clip the current clip in effect in device coordinates
244 * @param bs if non-null, a {@code BasicStroke} whose attributes
245 * should be applied to this operation
246 * @param thin true if the transformed stroke attributes are smaller
247 * than the minimum dropout pen width
248 * @param normalize true if the {@code VALUE_STROKE_NORMALIZE}
249 * {@code RenderingHint} is in effect
250 * @param bbox returns the bounds of the iteration
251 * @return the {@code AATileGenerator} instance to be consulted
252 * for tile coverages, or null if there is no output to render
253 * @since 1.7
254 */
255 public abstract AATileGenerator getAATileGenerator(Shape s,
256 AffineTransform at,
257 Region clip,
258 BasicStroke bs,
259 boolean thin,
260 boolean normalize,
261 int bbox[]);
262
263 /**
264 * Construct an antialiased tile generator for the given parallelogram
265 * store the bounds of the tile iteration in the bbox parameter.
266 * The parallelogram is specified as a starting point and 2 delta
267 * vectors that indicate the slopes of the 2 pairs of sides of the
268 * parallelogram.
269 * The 4 corners of the parallelogram are defined by the 4 points:
270 * <ul>
271 * <li> {@code x}, {@code y}
272 * <li> {@code x+dx1}, {@code y+dy1}
273 * <li> {@code x+dx1+dx2}, {@code y+dy1+dy2}
274 * <li> {@code x+dx2}, {@code y+dy2}
275 * </ul>
276 * The {@code lw1} and {@code lw2} parameters provide a specification
277 * for an optionally stroked parallelogram if they are positive numbers.
278 * The {@code lw1} parameter is the ratio of the length of the {@code dx1},
279 * {@code dx2} delta vector to half of the line width in that same
280 * direction.
281 * The {@code lw2} parameter provides the same ratio for the other delta
282 * vector.
283 * If {@code lw1} and {@code lw2} are both greater than zero, then
284 * the parallelogram figure is doubled by both expanding and contracting
285 * each delta vector by its corresponding {@code lw} value.
286 * If either (@code lw1) or {@code lw2} are also greater than 1, then
287 * the inner (contracted) parallelogram disappears and the figure is
288 * simply a single expanded parallelogram.
289 * The {@code clip} parameter specifies the current clip in effect
290 * in device coordinates and can be used to prune the data for the
291 * operation, but the renderer is not required to perform any
292 * clipping.
293 * <p>
294 * Upon returning, this method will fill the {@code bbox} parameter
295 * with 4 values indicating the bounds of the iteration of the
296 * tile generator.
297 * The iteration order of the tiles will be as specified by the
298 * pseudo-code:
299 * <pre>
300 * for (y = bbox[1]; y < bbox[3]; y += tileheight) {
301 * for (x = bbox[0]; x < bbox[2]; x += tilewidth) {
302 * }
303 * }
304 * </pre>
305 * If there is no output to be rendered, this method may return
306 * null.
307 *
308 * @param x the X coordinate of the first corner of the parallelogram
309 * @param y the Y coordinate of the first corner of the parallelogram
310 * @param dx1 the X coordinate delta of the first leg of the parallelogram
311 * @param dy1 the Y coordinate delta of the first leg of the parallelogram
312 * @param dx2 the X coordinate delta of the second leg of the parallelogram
313 * @param dy2 the Y coordinate delta of the second leg of the parallelogram
314 * @param lw1 the line width ratio for the first leg of the parallelogram
315 * @param lw2 the line width ratio for the second leg of the parallelogram
316 * @param clip the current clip in effect in device coordinates
317 * @param bbox returns the bounds of the iteration
318 * @return the {@code AATileGenerator} instance to be consulted
319 * for tile coverages, or null if there is no output to render
320 * @since 1.7
321 */
322 public abstract AATileGenerator getAATileGenerator(double x, double y,
323 double dx1, double dy1,
324 double dx2, double dy2,
325 double lw1, double lw2,
326 Region clip,
327 int bbox[]);
328
329 /**
330 * Returns the minimum pen width that the antialiasing rasterizer
331 * can represent without dropouts occurring.
332 * @since 1.7
333 */
334 public abstract float getMinimumAAPenSize();
335
336 /**
337 * Utility method to feed a {@link PathConsumer2D} object from a
338 * given {@link PathIterator}.
339 * This method deals with the details of running the iterator and
340 * feeding the consumer a segment at a time.
341 */
342 public static void feedConsumer(PathIterator pi, PathConsumer2D consumer) {
343 float coords[] = new float[6];
344 while (!pi.isDone()) {
345 switch (pi.currentSegment(coords)) {
346 case PathIterator.SEG_MOVETO:
347 consumer.moveTo(coords[0], coords[1]);
348 break;
349 case PathIterator.SEG_LINETO:
350 consumer.lineTo(coords[0], coords[1]);
351 break;
352 case PathIterator.SEG_QUADTO:
353 consumer.quadTo(coords[0], coords[1],
354 coords[2], coords[3]);
355 break;
356 case PathIterator.SEG_CUBICTO:
357 consumer.curveTo(coords[0], coords[1],
358 coords[2], coords[3],
359 coords[4], coords[5]);
360 break;
361 case PathIterator.SEG_CLOSE:
362 consumer.closePath();
363 break;
364 }
365 pi.next();
366 }
367 }
368
369 static class Tracer extends RenderingEngine {
370 RenderingEngine target;
371 String name;
372
373 public Tracer(RenderingEngine target) {
374 this.target = target;
375 name = target.getClass().getName();
376 }
377
378 public Shape createStrokedShape(Shape src,
379 float width,
380 int caps,
381 int join,
382 float miterlimit,
383 float dashes[],
384 float dashphase)
385 {
386 System.out.println(name+".createStrokedShape("+
387 src.getClass().getName()+", "+
388 "width = "+width+", "+
389 "caps = "+caps+", "+
390 "join = "+join+", "+
391 "miter = "+miterlimit+", "+
392 "dashes = "+dashes+", "+
393 "dashphase = "+dashphase+")");
394 return target.createStrokedShape(src,
395 width, caps, join, miterlimit,
396 dashes, dashphase);
397 }
398
399 public void strokeTo(Shape src,
400 AffineTransform at,
401 BasicStroke bs,
402 boolean thin,
403 boolean normalize,
404 boolean antialias,
405 PathConsumer2D consumer)
406 {
407 System.out.println(name+".strokeTo("+
408 src.getClass().getName()+", "+
409 at+", "+
410 bs+", "+
411 (thin ? "thin" : "wide")+", "+
412 (normalize ? "normalized" : "pure")+", "+
413 (antialias ? "AA" : "non-AA")+", "+
414 consumer.getClass().getName()+")");
415 target.strokeTo(src, at, bs, thin, normalize, antialias, consumer);
416 }
417
418 public float getMinimumAAPenSize() {
419 System.out.println(name+".getMinimumAAPenSize()");
420 return target.getMinimumAAPenSize();
421 }
422
423 public AATileGenerator getAATileGenerator(Shape s,
424 AffineTransform at,
425 Region clip,
426 BasicStroke bs,
427 boolean thin,
428 boolean normalize,
429 int bbox[])
430 {
431 System.out.println(name+".getAATileGenerator("+
432 s.getClass().getName()+", "+
433 at+", "+
434 clip+", "+
435 bs+", "+
436 (thin ? "thin" : "wide")+", "+
437 (normalize ? "normalized" : "pure")+")");
438 return target.getAATileGenerator(s, at, clip,
439 bs, thin, normalize,
440 bbox);
441 }
442 public AATileGenerator getAATileGenerator(double x, double y,
443 double dx1, double dy1,
444 double dx2, double dy2,
445 double lw1, double lw2,
446 Region clip,
447 int bbox[])
448 {
449 System.out.println(name+".getAATileGenerator("+
450 x+", "+y+", "+
451 dx1+", "+dy1+", "+
452 dx2+", "+dy2+", "+
453 lw1+", "+lw2+", "+
454 clip+")");
455 return target.getAATileGenerator(x, y,
456 dx1, dy1,
457 dx2, dy2,
458 lw1, lw2,
459 clip, bbox);
460 }
461 }
462 }