J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2007 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any 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 java.util.ServiceLoader; |
| 36 | import sun.security.action.GetPropertyAction; |
| 37 | |
| 38 | import sun.awt.geom.PathConsumer2D; |
| 39 | |
| 40 | /** |
| 41 | * This class abstracts a number of features for which the Java 2D |
| 42 | * implementation relies on proprietary licensed software libraries. |
| 43 | * Access to those features is now achieved by retrieving the singleton |
| 44 | * instance of this class and calling the appropriate methods on it. |
| 45 | * The 3 primary features abstracted here include: |
| 46 | * <dl> |
| 47 | * <dt>Shape createStrokedShape(Shape, [BasicStroke attributes]); |
| 48 | * <dd>This method implements the functionality of the method of the |
| 49 | * same name on the {@link BasicStroke} class. |
| 50 | * <dt>void strokeTo(Shape, [rendering parameters], PathConsumer2D); |
| 51 | * <dd>This method performs widening of the source path on the fly |
| 52 | * and sends the results to the given {@link PathConsumer2D} object. |
| 53 | * This procedure avoids having to create an intermediate Shape |
| 54 | * object to hold the results of the {@code createStrokedShape} method. |
| 55 | * The main user of this method is the Java 2D non-antialiasing renderer. |
| 56 | * <dt>AATileGenerator getAATileGenerator(Shape, [rendering parameters]); |
| 57 | * <dd>This method returns an object which can iterate over the |
| 58 | * specified bounding box and produce tiles of coverage values for |
| 59 | * antialiased rendering. The details of the operation of the |
| 60 | * {@link AATileGenerator} object are explained in its class comments. |
| 61 | * </dl> |
| 62 | * Additionally, the following informational method supplies important |
| 63 | * data about the implementation. |
| 64 | * <dl> |
| 65 | * <dt>float getMinimumAAPenSize() |
| 66 | * <dd>This method provides information on how small the BasicStroke |
| 67 | * line width can get before dropouts occur. Rendering with a BasicStroke |
| 68 | * is defined to never allow the line to have breaks, gaps, or dropouts |
| 69 | * even if the width is set to 0.0f, so this information allows the |
| 70 | * {@link SunGraphics2D} class to detect the "thin line" case and set |
| 71 | * the rendering attributes accordingly. |
| 72 | * </dl> |
| 73 | * At startup the runtime will load a single instance of this class. |
| 74 | * It searches the classpath for a registered provider of this API |
| 75 | * and returns either the last one it finds, or the instance whose |
| 76 | * class name matches the value supplied in the System property |
| 77 | * {@code sun.java2d.renderer}. |
| 78 | * Additionally, a runtime System property flag can be set to trace |
| 79 | * all calls to methods on the {@code RenderingEngine} in use by |
| 80 | * setting the sun.java2d.renderer.trace property to any non-null value. |
| 81 | * <p> |
| 82 | * Parts of the system that need to use any of the above features should |
| 83 | * call {@code RenderingEngine.getInstance()} to obtain the properly |
| 84 | * registered (and possibly trace-enabled) version of the RenderingEngine. |
| 85 | */ |
| 86 | public abstract class RenderingEngine { |
| 87 | private static RenderingEngine reImpl; |
| 88 | |
| 89 | /** |
| 90 | * Returns an instance of {@code RenderingEngine} as determined |
| 91 | * by the installation environment and runtime flags. |
| 92 | * <p> |
| 93 | * A specific instance of the {@code RenderingEngine} can be |
| 94 | * chosen by specifying the runtime flag: |
| 95 | * <pre> |
| 96 | * java -Dsun.java2d.renderer=<classname> |
| 97 | * </pre> |
| 98 | * If no specific {@code RenderingEngine} is specified on the command |
| 99 | * line then the last one returned by enumerating all subclasses of |
| 100 | * {@code RenderingEngine} known to the ServiceLoader is used. |
| 101 | * <p> |
| 102 | * Runtime tracing of the actions of the {@code RenderingEngine} |
| 103 | * can be enabled by specifying the runtime flag: |
| 104 | * <pre> |
| 105 | * java -Dsun.java2d.renderer.trace=<any string> |
| 106 | * </pre> |
| 107 | * @return an instance of {@code RenderingEngine} |
| 108 | * @since 1.7 |
| 109 | */ |
| 110 | public static synchronized RenderingEngine getInstance() { |
| 111 | if (reImpl != null) { |
| 112 | return reImpl; |
| 113 | } |
| 114 | |
| 115 | reImpl = (RenderingEngine) |
| 116 | AccessController.doPrivileged(new PrivilegedAction() { |
| 117 | public Object run() { |
| 118 | String reClass = |
| 119 | System.getProperty("sun.java2d.renderer", |
| 120 | "sun.dc.DuctusRenderingEngine"); |
| 121 | |
| 122 | ServiceLoader<RenderingEngine> reLoader = |
| 123 | ServiceLoader.loadInstalled(RenderingEngine.class); |
| 124 | |
| 125 | RenderingEngine service = null; |
| 126 | |
| 127 | for (RenderingEngine re : reLoader) { |
| 128 | service = re; |
| 129 | if (re.getClass().getName().equals(reClass)) { |
| 130 | break; |
| 131 | } |
| 132 | } |
| 133 | return service; |
| 134 | } |
| 135 | }); |
| 136 | |
| 137 | if (reImpl == null) { |
| 138 | throw new InternalError("No RenderingEngine module found"); |
| 139 | } |
| 140 | |
| 141 | GetPropertyAction gpa = |
| 142 | new GetPropertyAction("sun.java2d.renderer.trace"); |
| 143 | String reTrace = (String) AccessController.doPrivileged(gpa); |
| 144 | if (reTrace != null) { |
| 145 | reImpl = new Tracer(reImpl); |
| 146 | } |
| 147 | |
| 148 | return reImpl; |
| 149 | } |
| 150 | |
| 151 | /** |
| 152 | * Create a widened path as specified by the parameters. |
| 153 | * <p> |
| 154 | * The specified {@code src} {@link Shape} is widened according |
| 155 | * to the specified attribute parameters as per the |
| 156 | * {@link BasicStroke} specification. |
| 157 | * |
| 158 | * @param src the source path to be widened |
| 159 | * @param width the width of the widened path as per {@code BasicStroke} |
| 160 | * @param caps the end cap decorations as per {@code BasicStroke} |
| 161 | * @param join the segment join decorations as per {@code BasicStroke} |
| 162 | * @param miterlimit the miter limit as per {@code BasicStroke} |
| 163 | * @param dashes the dash length array as per {@code BasicStroke} |
| 164 | * @param dashphase the initial dash phase as per {@code BasicStroke} |
| 165 | * @return the widened path stored in a new {@code Shape} object |
| 166 | * @since 1.7 |
| 167 | */ |
| 168 | public abstract Shape createStrokedShape(Shape src, |
| 169 | float width, |
| 170 | int caps, |
| 171 | int join, |
| 172 | float miterlimit, |
| 173 | float dashes[], |
| 174 | float dashphase); |
| 175 | |
| 176 | /** |
| 177 | * Sends the geometry for a widened path as specified by the parameters |
| 178 | * to the specified consumer. |
| 179 | * <p> |
| 180 | * The specified {@code src} {@link Shape} is widened according |
| 181 | * to the parameters specified by the {@link BasicStroke} object. |
| 182 | * Adjustments are made to the path as appropriate for the |
| 183 | * {@link VALUE_STROKE_NORMALIZE} hint if the {@code normalize} |
| 184 | * boolean parameter is true. |
| 185 | * Adjustments are made to the path as appropriate for the |
| 186 | * {@link VALUE_ANTIALIAS_ON} hint if the {@code antialias} |
| 187 | * boolean parameter is true. |
| 188 | * <p> |
| 189 | * The geometry of the widened path is forwarded to the indicated |
| 190 | * {@link PathConsumer2D} object as it is calculated. |
| 191 | * |
| 192 | * @param src the source path to be widened |
| 193 | * @param bs the {@code BasicSroke} object specifying the |
| 194 | * decorations to be applied to the widened path |
| 195 | * @param normalize indicates whether stroke normalization should |
| 196 | * be applied |
| 197 | * @param antialias indicates whether or not adjustments appropriate |
| 198 | * to antialiased rendering should be applied |
| 199 | * @param consumer the {@code PathConsumer2D} instance to forward |
| 200 | * the widened geometry to |
| 201 | * @since 1.7 |
| 202 | */ |
| 203 | public abstract void strokeTo(Shape src, |
| 204 | AffineTransform at, |
| 205 | BasicStroke bs, |
| 206 | boolean thin, |
| 207 | boolean normalize, |
| 208 | boolean antialias, |
| 209 | PathConsumer2D consumer); |
| 210 | |
| 211 | /** |
| 212 | * Construct an antialiased tile generator for the given shape with |
| 213 | * the given rendering attributes and store the bounds of the tile |
| 214 | * iteration in the bbox parameter. |
| 215 | * The {@code at} parameter specifies a transform that should affect |
| 216 | * both the shape and the {@code BasicStroke} attributes. |
| 217 | * The {@code clip} parameter specifies the current clip in effect |
| 218 | * in device coordinates and can be used to prune the data for the |
| 219 | * operation, but the renderer is not required to perform any |
| 220 | * clipping. |
| 221 | * If the {@code BasicStroke} parameter is null then the shape |
| 222 | * should be filled as is, otherwise the attributes of the |
| 223 | * {@code BasicStroke} should be used to specify a draw operation. |
| 224 | * The {@code thin} parameter indicates whether or not the |
| 225 | * transformed {@code BasicStroke} represents coordinates smaller |
| 226 | * than the minimum resolution of the antialiasing rasterizer as |
| 227 | * specified by the {@code getMinimumAAPenWidth()} method. |
| 228 | * <p> |
| 229 | * Upon returning, this method will fill the {@code bbox} parameter |
| 230 | * with 4 values indicating the bounds of the iteration of the |
| 231 | * tile generator. |
| 232 | * The iteration order of the tiles will be as specified by the |
| 233 | * pseudo-code: |
| 234 | * <pre> |
| 235 | * for (y = bbox[1]; y < bbox[3]; y += tileheight) { |
| 236 | * for (x = bbox[0]; x < bbox[2]; x += tilewidth) { |
| 237 | * } |
| 238 | * } |
| 239 | * </pre> |
| 240 | * If there is no output to be rendered, this method may return |
| 241 | * null. |
| 242 | * |
| 243 | * @param s the shape to be rendered (fill or draw) |
| 244 | * @param at the transform to be applied to the shape and the |
| 245 | * stroke attributes |
| 246 | * @param clip the current clip in effect in device coordinates |
| 247 | * @param bs if non-null, a {@code BasicStroke} whose attributes |
| 248 | * should be applied to this operation |
| 249 | * @param thin true if the transformed stroke attributes are smaller |
| 250 | * than the minimum dropout pen width |
| 251 | * @param normalize true if the {@code VALUE_STROKE_NORMALIZE} |
| 252 | * {@code RenderingHint} is in effect |
| 253 | * @param bbox returns the bounds of the iteration |
| 254 | * @return the {@code AATileGenerator} instance to be consulted |
| 255 | * for tile coverages, or null if there is no output to render |
| 256 | * @since 1.7 |
| 257 | */ |
| 258 | public abstract AATileGenerator getAATileGenerator(Shape s, |
| 259 | AffineTransform at, |
| 260 | Region clip, |
| 261 | BasicStroke bs, |
| 262 | boolean thin, |
| 263 | boolean normalize, |
| 264 | int bbox[]); |
| 265 | |
| 266 | /** |
| 267 | * Returns the minimum pen width that the antialiasing rasterizer |
| 268 | * can represent without dropouts occuring. |
| 269 | * @since 1.7 |
| 270 | */ |
| 271 | public abstract float getMinimumAAPenSize(); |
| 272 | |
| 273 | /** |
| 274 | * Utility method to feed a {@link PathConsumer2D} object from a |
| 275 | * given {@link PathIterator}. |
| 276 | * This method deals with the details of running the iterator and |
| 277 | * feeding the consumer a segment at a time. |
| 278 | */ |
| 279 | public static void feedConsumer(PathIterator pi, PathConsumer2D consumer) { |
| 280 | float coords[] = new float[6]; |
| 281 | while (!pi.isDone()) { |
| 282 | switch (pi.currentSegment(coords)) { |
| 283 | case PathIterator.SEG_MOVETO: |
| 284 | consumer.moveTo(coords[0], coords[1]); |
| 285 | break; |
| 286 | case PathIterator.SEG_LINETO: |
| 287 | consumer.lineTo(coords[0], coords[1]); |
| 288 | break; |
| 289 | case PathIterator.SEG_QUADTO: |
| 290 | consumer.quadTo(coords[0], coords[1], |
| 291 | coords[2], coords[3]); |
| 292 | break; |
| 293 | case PathIterator.SEG_CUBICTO: |
| 294 | consumer.curveTo(coords[0], coords[1], |
| 295 | coords[2], coords[3], |
| 296 | coords[4], coords[5]); |
| 297 | break; |
| 298 | case PathIterator.SEG_CLOSE: |
| 299 | consumer.closePath(); |
| 300 | break; |
| 301 | } |
| 302 | pi.next(); |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | static class Tracer extends RenderingEngine { |
| 307 | RenderingEngine target; |
| 308 | String name; |
| 309 | |
| 310 | public Tracer(RenderingEngine target) { |
| 311 | this.target = target; |
| 312 | name = target.getClass().getName(); |
| 313 | } |
| 314 | |
| 315 | public Shape createStrokedShape(Shape src, |
| 316 | float width, |
| 317 | int caps, |
| 318 | int join, |
| 319 | float miterlimit, |
| 320 | float dashes[], |
| 321 | float dashphase) |
| 322 | { |
| 323 | System.out.println(name+".createStrokedShape("+ |
| 324 | src.getClass().getName()+", "+ |
| 325 | "width = "+width+", "+ |
| 326 | "caps = "+caps+", "+ |
| 327 | "join = "+join+", "+ |
| 328 | "miter = "+miterlimit+", "+ |
| 329 | "dashes = "+dashes+", "+ |
| 330 | "dashphase = "+dashphase+")"); |
| 331 | return target.createStrokedShape(src, |
| 332 | width, caps, join, miterlimit, |
| 333 | dashes, dashphase); |
| 334 | } |
| 335 | |
| 336 | public void strokeTo(Shape src, |
| 337 | AffineTransform at, |
| 338 | BasicStroke bs, |
| 339 | boolean thin, |
| 340 | boolean normalize, |
| 341 | boolean antialias, |
| 342 | PathConsumer2D consumer) |
| 343 | { |
| 344 | System.out.println(name+".strokeTo("+ |
| 345 | src.getClass().getName()+", "+ |
| 346 | at+", "+ |
| 347 | bs+", "+ |
| 348 | (thin ? "thin" : "wide")+", "+ |
| 349 | (normalize ? "normalized" : "pure")+", "+ |
| 350 | (antialias ? "AA" : "non-AA")+", "+ |
| 351 | consumer.getClass().getName()+")"); |
| 352 | target.strokeTo(src, at, bs, thin, normalize, antialias, consumer); |
| 353 | } |
| 354 | |
| 355 | public float getMinimumAAPenSize() { |
| 356 | System.out.println(name+".getMinimumAAPenSize()"); |
| 357 | return target.getMinimumAAPenSize(); |
| 358 | } |
| 359 | |
| 360 | public AATileGenerator getAATileGenerator(Shape s, |
| 361 | AffineTransform at, |
| 362 | Region clip, |
| 363 | BasicStroke bs, |
| 364 | boolean thin, |
| 365 | boolean normalize, |
| 366 | int bbox[]) |
| 367 | { |
| 368 | System.out.println(name+".getAATileGenerator("+ |
| 369 | s.getClass().getName()+", "+ |
| 370 | at+", "+ |
| 371 | clip+", "+ |
| 372 | bs+", "+ |
| 373 | (thin ? "thin" : "wide")+", "+ |
| 374 | (normalize ? "normalized" : "pure")+")"); |
| 375 | return target.getAATileGenerator(s, at, clip, |
| 376 | bs, thin, normalize, |
| 377 | bbox); |
| 378 | } |
| 379 | } |
| 380 | } |