J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2006 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.font; |
| 27 | |
| 28 | import java.awt.Font; |
| 29 | import java.awt.font.GlyphVector; |
| 30 | import java.awt.font.FontRenderContext; |
| 31 | import sun.java2d.loops.FontInfo; |
| 32 | |
| 33 | /* |
| 34 | * This class represents a list of actual renderable glyphs. |
| 35 | * It can be constructed from a number of text sources, representing |
| 36 | * the various ways in which a programmer can ask a Graphics2D object |
| 37 | * to render some text. Once constructed, it provides a way of iterating |
| 38 | * through the device metrics and graybits of the individual glyphs that |
| 39 | * need to be rendered to the screen. |
| 40 | * |
| 41 | * Note that this class holds pointers to native data which must be |
| 42 | * disposed. It is not marked as finalizable since it is intended |
| 43 | * to be very lightweight and finalization is a comparitively expensive |
| 44 | * procedure. The caller must specifically use try{} finally{} to |
| 45 | * manually ensure that the object is disposed after use, otherwise |
| 46 | * native data structures might be leaked. |
| 47 | * |
| 48 | * Here is a code sample for using this class: |
| 49 | * |
| 50 | * public void drawString(String str, FontInfo info, float x, float y) { |
| 51 | * GlyphList gl = GlyphList.getInstance(); |
| 52 | * try { |
| 53 | * gl.setFromString(info, str, x, y); |
| 54 | * int strbounds[] = gl.getBounds(); |
| 55 | * int numglyphs = gl.getNumGlyphs(); |
| 56 | * for (int i = 0; i < numglyphs; i++) { |
| 57 | * gl.setGlyphIndex(i); |
| 58 | * int metrics[] = gl.getMetrics(); |
| 59 | * byte bits[] = gl.getGrayBits(); |
| 60 | * int glyphx = metrics[0]; |
| 61 | * int glyphy = metrics[1]; |
| 62 | * int glyphw = metrics[2]; |
| 63 | * int glyphh = metrics[3]; |
| 64 | * int off = 0; |
| 65 | * for (int j = 0; j < glyphh; j++) { |
| 66 | * for (int i = 0; i < glyphw; i++) { |
| 67 | * int dx = glyphx + i; |
| 68 | * int dy = glyphy + j; |
| 69 | * int alpha = bits[off++]; |
| 70 | * drawPixel(alpha, dx, dy); |
| 71 | * } |
| 72 | * } |
| 73 | * } |
| 74 | * } finally { |
| 75 | * gl.dispose(); |
| 76 | * } |
| 77 | * } |
| 78 | */ |
| 79 | public final class GlyphList { |
| 80 | private static final int MINGRAYLENGTH = 1024; |
| 81 | private static final int MAXGRAYLENGTH = 8192; |
| 82 | private static final int DEFAULT_LENGTH = 32; |
| 83 | |
| 84 | int glyphindex; |
| 85 | int metrics[]; |
| 86 | byte graybits[]; |
| 87 | |
| 88 | /* A reference to the strike is needed for the case when the GlyphList |
| 89 | * may be added to a queue for batch processing, (e.g. OpenGL) and we need |
| 90 | * to be completely certain that the strike is still valid when the glyphs |
| 91 | * images are later referenced. This does mean that if such code discards |
| 92 | * GlyphList and places only the data it contains on the queue, that the |
| 93 | * strike needs to be part of that data held by a strong reference. |
| 94 | * In the cases of drawString() and drawChars(), this is a single strike, |
| 95 | * although it may be a composite strike. In the case of |
| 96 | * drawGlyphVector() it may be a single strike, or a list of strikes. |
| 97 | */ |
| 98 | Object strikelist; // hold multiple strikes during rendering of complex gv |
| 99 | |
| 100 | /* In normal usage, the same GlyphList will get recycled, so |
| 101 | * it makes sense to allocate arrays that will get reused along with |
| 102 | * it, rather than generating garbage. Garbage will be generated only |
| 103 | * in MP envts where multiple threads are executing. Throughput should |
| 104 | * still be higher in those cases. |
| 105 | */ |
| 106 | int len = 0; |
| 107 | int maxLen = 0; |
| 108 | int maxPosLen = 0; |
| 109 | int glyphData[]; |
| 110 | char chData[]; |
| 111 | long images[]; |
| 112 | float positions[]; |
| 113 | float x, y; |
| 114 | float gposx, gposy; |
| 115 | boolean usePositions; |
| 116 | |
| 117 | /* lcdRGBOrder is used only by LCD text rendering. Its here because |
| 118 | * the Graphics may have a different hint value than the one used |
| 119 | * by a GlyphVector, so it has to be stored here - and is obtained |
| 120 | * from the right FontInfo. Another approach would have been to have |
| 121 | * install a separate pipe for that case but that's a lot of extra |
| 122 | * code when a simple boolean will suffice. The overhead to non-LCD |
| 123 | * text is a redundant boolean assign per call. |
| 124 | */ |
| 125 | boolean lcdRGBOrder; |
| 126 | |
| 127 | /* |
| 128 | * lcdSubPixPos is used only by LCD text rendering. Its here because |
| 129 | * the Graphics may have a different hint value than the one used |
| 130 | * by a GlyphVector, so it has to be stored here - and is obtained |
| 131 | * from the right FontInfo. Its also needed by the code which |
| 132 | * calculates glyph positions which already needs to access this |
| 133 | * GlyphList and would otherwise need the FontInfo. |
| 134 | * This is true only if LCD text and fractional metrics hints |
| 135 | * are selected on the graphics. |
| 136 | * When this is true and the glyph positions as determined by the |
| 137 | * advances are non-integral, it requests adjustment of the positions. |
| 138 | * Setting this for surfaces which do not support it through accelerated |
| 139 | * loops may cause a slow-down as software loops are invoked instead. |
| 140 | */ |
| 141 | boolean lcdSubPixPos; |
| 142 | |
| 143 | /* This scheme creates a singleton GlyphList which is checked out |
| 144 | * for use. Callers who find its checked out create one that after use |
| 145 | * is discarded. This means that in a MT-rendering environment, |
| 146 | * there's no need to synchronise except for that one instance. |
| 147 | * Fewer threads will then need to synchronise, perhaps helping |
| 148 | * throughput on a MP system. If for some reason the reusable |
| 149 | * GlyphList is checked out for a long time (or never returned?) then |
| 150 | * we would end up always creating new ones. That situation should not |
| 151 | * occur and if if did, it would just lead to some extra garbage being |
| 152 | * created. |
| 153 | */ |
| 154 | private static GlyphList reusableGL = new GlyphList(); |
| 155 | private static boolean inUse; |
| 156 | |
| 157 | |
| 158 | void ensureCapacity(int len) { |
| 159 | /* Note len must not be -ve! only setFromChars should be capable |
| 160 | * of passing down a -ve len, and this guards against it. |
| 161 | */ |
| 162 | if (len < 0) { |
| 163 | len = 0; |
| 164 | } |
| 165 | if (usePositions && len > maxPosLen) { |
| 166 | positions = new float[len * 2 + 2]; |
| 167 | maxPosLen = len; |
| 168 | } |
| 169 | |
| 170 | if (maxLen == 0 || len > maxLen) { |
| 171 | glyphData = new int[len]; |
| 172 | chData = new char[len]; |
| 173 | images = new long[len]; |
| 174 | maxLen = len; |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | private GlyphList() { |
| 179 | // ensureCapacity(DEFAULT_LENGTH); |
| 180 | } |
| 181 | |
| 182 | // private GlyphList(int arraylen) { |
| 183 | // ensureCapacity(arraylen); |
| 184 | // } |
| 185 | |
| 186 | public static GlyphList getInstance() { |
| 187 | /* The following heuristic is that if the reusable instance is |
| 188 | * in use, it probably still will be in a micro-second, so avoid |
| 189 | * synchronising on the class and just allocate a new instance. |
| 190 | * The cost is one extra boolean test for the normal case, and some |
| 191 | * small number of cases where we allocate an extra object when |
| 192 | * in fact the reusable one would be freed very soon. |
| 193 | */ |
| 194 | if (inUse) { |
| 195 | return new GlyphList(); |
| 196 | } else { |
| 197 | synchronized(GlyphList.class) { |
| 198 | if (inUse) { |
| 199 | return new GlyphList(); |
| 200 | } else { |
| 201 | inUse = true; |
| 202 | return reusableGL; |
| 203 | } |
| 204 | } |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | /* In some cases the caller may be able to estimate the size of |
| 209 | * array needed, and it will usually be long enough. This avoids |
| 210 | * the unnecessary reallocation that occurs if our default |
| 211 | * values are too small. This is useful because this object |
| 212 | * will be discarded so the re-allocation overhead is high. |
| 213 | */ |
| 214 | // public static GlyphList getInstance(int sz) { |
| 215 | // if (inUse) { |
| 216 | // return new GlyphList(sz); |
| 217 | // } else { |
| 218 | // synchronized(GlyphList.class) { |
| 219 | // if (inUse) { |
| 220 | // return new GlyphList(); |
| 221 | // } else { |
| 222 | // inUse = true; |
| 223 | // return reusableGL; |
| 224 | // } |
| 225 | // } |
| 226 | // } |
| 227 | // } |
| 228 | |
| 229 | /* GlyphList is in an invalid state until setFrom* method is called. |
| 230 | * After obtaining a new GlyphList it is the caller's responsibility |
| 231 | * that one of these methods is executed before handing off the |
| 232 | * GlyphList |
| 233 | */ |
| 234 | |
| 235 | public boolean setFromString(FontInfo info, String str, float x, float y) { |
| 236 | this.x = x; |
| 237 | this.y = y; |
| 238 | this.strikelist = info.fontStrike; |
| 239 | this.lcdRGBOrder = info.lcdRGBOrder; |
| 240 | this.lcdSubPixPos = info.lcdSubPixPos; |
| 241 | len = str.length(); |
| 242 | ensureCapacity(len); |
| 243 | str.getChars(0, len, chData, 0); |
| 244 | return mapChars(info, len); |
| 245 | } |
| 246 | |
| 247 | public boolean setFromChars(FontInfo info, char[] chars, int off, int alen, |
| 248 | float x, float y) { |
| 249 | this.x = x; |
| 250 | this.y = y; |
| 251 | this.strikelist = info.fontStrike; |
| 252 | this.lcdRGBOrder = info.lcdRGBOrder; |
| 253 | this.lcdSubPixPos = info.lcdSubPixPos; |
| 254 | len = alen; |
| 255 | if (alen < 0) { |
| 256 | len = 0; |
| 257 | } else { |
| 258 | len = alen; |
| 259 | } |
| 260 | ensureCapacity(len); |
| 261 | System.arraycopy(chars, off, chData, 0, len); |
| 262 | return mapChars(info, len); |
| 263 | } |
| 264 | |
| 265 | private final boolean mapChars(FontInfo info, int len) { |
| 266 | /* REMIND.Is it worthwhile for the iteration to convert |
| 267 | * chars to glyph ids to directly map to images? |
| 268 | */ |
| 269 | if (info.font2D.getMapper().charsToGlyphsNS(len, chData, glyphData)) { |
| 270 | return false; |
| 271 | } |
| 272 | info.fontStrike.getGlyphImagePtrs(glyphData, images, len); |
| 273 | glyphindex = -1; |
| 274 | return true; |
| 275 | } |
| 276 | |
| 277 | |
| 278 | public void setFromGlyphVector(FontInfo info, GlyphVector gv, |
| 279 | float x, float y) { |
| 280 | this.x = x; |
| 281 | this.y = y; |
| 282 | this.lcdRGBOrder = info.lcdRGBOrder; |
| 283 | this.lcdSubPixPos = info.lcdSubPixPos; |
| 284 | /* A GV may be rendered in different Graphics. It is possible it is |
| 285 | * used for one case where LCD text is available, and another where |
| 286 | * it is not. Pass in the "info". to ensure get a suitable one. |
| 287 | */ |
| 288 | StandardGlyphVector sgv = StandardGlyphVector.getStandardGV(gv, info); |
| 289 | // call before ensureCapacity :- |
| 290 | usePositions = sgv.needsPositions(info.devTx); |
| 291 | len = sgv.getNumGlyphs(); |
| 292 | ensureCapacity(len); |
| 293 | strikelist = sgv.setupGlyphImages(images, |
| 294 | usePositions ? positions : null, |
| 295 | info.devTx); |
| 296 | glyphindex = -1; |
| 297 | } |
| 298 | |
| 299 | public int[] getBounds() { |
| 300 | /* We co-opt the 5 element array that holds per glyph metrics in order |
| 301 | * to return the bounds. So a caller must copy the data out of the |
| 302 | * array before calling any other methods on this GlyphList |
| 303 | */ |
| 304 | if (glyphindex >= 0) { |
| 305 | throw new InternalError("calling getBounds after setGlyphIndex"); |
| 306 | } |
| 307 | if (metrics == null) { |
| 308 | metrics = new int[5]; |
| 309 | } |
| 310 | /* gposx and gposy are used to accumulate the advance. |
| 311 | * Add 0.5f for consistent rounding to pixel position. */ |
| 312 | gposx = x + 0.5f; |
| 313 | gposy = y + 0.5f; |
| 314 | fillBounds(metrics); |
| 315 | return metrics; |
| 316 | } |
| 317 | |
| 318 | /* This method now assumes "state", so must be called 0->len |
| 319 | * The metrics it returns are accumulated on the fly |
| 320 | * So it could be renamed "nextGlyph()". |
| 321 | * Note that a laid out GlyphVector which has assigned glyph positions |
| 322 | * doesn't have this stricture.. |
| 323 | */ |
| 324 | public void setGlyphIndex(int i) { |
| 325 | glyphindex = i; |
| 326 | float gx = |
| 327 | StrikeCache.unsafe.getFloat(images[i]+StrikeCache.topLeftXOffset); |
| 328 | float gy = |
| 329 | StrikeCache.unsafe.getFloat(images[i]+StrikeCache.topLeftYOffset); |
| 330 | |
| 331 | if (usePositions) { |
| 332 | metrics[0] = (int)Math.floor(positions[(i<<1)] + gposx + gx); |
| 333 | metrics[1] = (int)Math.floor(positions[(i<<1)+1] + gposy + gy); |
| 334 | } else { |
| 335 | metrics[0] = (int)Math.floor(gposx + gx); |
| 336 | metrics[1] = (int)Math.floor(gposy + gy); |
| 337 | /* gposx and gposy are used to accumulate the advance */ |
| 338 | gposx += StrikeCache.unsafe.getFloat |
| 339 | (images[i]+StrikeCache.xAdvanceOffset); |
| 340 | gposy += StrikeCache.unsafe.getFloat |
| 341 | (images[i]+StrikeCache.yAdvanceOffset); |
| 342 | } |
| 343 | metrics[2] = |
| 344 | StrikeCache.unsafe.getChar(images[i]+StrikeCache.widthOffset); |
| 345 | metrics[3] = |
| 346 | StrikeCache.unsafe.getChar(images[i]+StrikeCache.heightOffset); |
| 347 | metrics[4] = |
| 348 | StrikeCache.unsafe.getChar(images[i]+StrikeCache.rowBytesOffset); |
| 349 | } |
| 350 | |
| 351 | public int[] getMetrics() { |
| 352 | return metrics; |
| 353 | } |
| 354 | |
| 355 | public byte[] getGrayBits() { |
| 356 | int len = metrics[4] * metrics[3]; |
| 357 | if (graybits == null) { |
| 358 | graybits = new byte[Math.max(len, MINGRAYLENGTH)]; |
| 359 | } else { |
| 360 | if (len > graybits.length) { |
| 361 | graybits = new byte[len]; |
| 362 | } |
| 363 | } |
| 364 | long pixelDataAddress; |
| 365 | if (StrikeCache.nativeAddressSize == 4) { |
| 366 | pixelDataAddress = 0xffffffff & |
| 367 | StrikeCache.unsafe.getInt(images[glyphindex] + |
| 368 | StrikeCache.pixelDataOffset); |
| 369 | } else { |
| 370 | pixelDataAddress = |
| 371 | StrikeCache.unsafe.getLong(images[glyphindex] + |
| 372 | StrikeCache.pixelDataOffset); |
| 373 | } |
| 374 | if (pixelDataAddress == 0L) { |
| 375 | return graybits; |
| 376 | } |
| 377 | /* unsafe is supposed to be fast, but I doubt if this loop can beat |
| 378 | * a native call which does a getPrimitiveArrayCritical and a |
| 379 | * memcpy for the typical amount of image data (30-150 bytes) |
| 380 | * Consider a native method if there is a performance problem (which |
| 381 | * I haven't seen so far). |
| 382 | */ |
| 383 | for (int i=0; i<len; i++) { |
| 384 | graybits[i] = StrikeCache.unsafe.getByte(pixelDataAddress+i); |
| 385 | } |
| 386 | return graybits; |
| 387 | } |
| 388 | |
| 389 | public long[] getImages() { |
| 390 | return images; |
| 391 | } |
| 392 | |
| 393 | public boolean usePositions() { |
| 394 | return usePositions; |
| 395 | } |
| 396 | |
| 397 | public float[] getPositions() { |
| 398 | return positions; |
| 399 | } |
| 400 | |
| 401 | public float getX() { |
| 402 | return x; |
| 403 | } |
| 404 | |
| 405 | public float getY() { |
| 406 | return y; |
| 407 | } |
| 408 | |
| 409 | public Object getStrike() { |
| 410 | return strikelist; |
| 411 | } |
| 412 | |
| 413 | public boolean isSubPixPos() { |
| 414 | return lcdSubPixPos; |
| 415 | } |
| 416 | |
| 417 | public boolean isRGBOrder() { |
| 418 | return lcdRGBOrder; |
| 419 | } |
| 420 | |
| 421 | /* There's a reference equality test overhead here, but it allows us |
| 422 | * to avoid synchronizing for GL's that will just be GC'd. This |
| 423 | * helps MP throughput. |
| 424 | */ |
| 425 | public void dispose() { |
| 426 | if (this == reusableGL) { |
| 427 | if (graybits != null && graybits.length > MAXGRAYLENGTH) { |
| 428 | graybits = null; |
| 429 | } |
| 430 | usePositions = false; |
| 431 | strikelist = null; // remove reference to the strike list |
| 432 | inUse = false; |
| 433 | } |
| 434 | } |
| 435 | |
| 436 | /* The value here is for use by the rendering engine as it reflects |
| 437 | * the number of glyphs in the array to be blitted. Surrogates pairs |
| 438 | * may have two slots (the second of these being a dummy entry of the |
| 439 | * invisible glyph), whereas an application client would expect only |
| 440 | * one glyph. In other words don't propagate this value up to client code. |
| 441 | * |
| 442 | * {dlf} an application client should have _no_ expectations about the |
| 443 | * number of glyphs per char. This ultimately depends on the font |
| 444 | * technology and layout process used, which in general clients will |
| 445 | * know nothing about. |
| 446 | */ |
| 447 | public int getNumGlyphs() { |
| 448 | return len; |
| 449 | } |
| 450 | |
| 451 | /* We re-do all this work as we iterate through the glyphs |
| 452 | * but it seems unavoidable without re-working the Java TextRenderers. |
| 453 | */ |
| 454 | private void fillBounds(int[] bounds) { |
| 455 | /* Faster to access local variables in the for loop? */ |
| 456 | int xOffset = StrikeCache.topLeftXOffset; |
| 457 | int yOffset = StrikeCache.topLeftYOffset; |
| 458 | int wOffset = StrikeCache.widthOffset; |
| 459 | int hOffset = StrikeCache.heightOffset; |
| 460 | int xAdvOffset = StrikeCache.xAdvanceOffset; |
| 461 | int yAdvOffset = StrikeCache.yAdvanceOffset; |
| 462 | |
| 463 | if (len == 0) { |
| 464 | bounds[0] = bounds[1] = bounds[2] = bounds[3] = 0; |
| 465 | return; |
| 466 | } |
| 467 | float bx0, by0, bx1, by1; |
| 468 | bx0 = by0 = Float.POSITIVE_INFINITY; |
| 469 | bx1 = by1 = Float.NEGATIVE_INFINITY; |
| 470 | |
| 471 | int posIndex = 0; |
| 472 | float glx = x + 0.5f; |
| 473 | float gly = y + 0.5f; |
| 474 | char gw, gh; |
| 475 | float gx, gy, gx0, gy0, gx1, gy1; |
| 476 | for (int i=0; i<len; i++) { |
| 477 | gx = StrikeCache.unsafe.getFloat(images[i]+xOffset); |
| 478 | gy = StrikeCache.unsafe.getFloat(images[i]+yOffset); |
| 479 | gw = StrikeCache.unsafe.getChar(images[i]+wOffset); |
| 480 | gh = StrikeCache.unsafe.getChar(images[i]+hOffset); |
| 481 | |
| 482 | if (usePositions) { |
| 483 | gx0 = positions[posIndex++] + gx + glx; |
| 484 | gy0 = positions[posIndex++] + gy + gly; |
| 485 | } else { |
| 486 | gx0 = glx + gx; |
| 487 | gy0 = gly + gy; |
| 488 | glx += StrikeCache.unsafe.getFloat(images[i]+xAdvOffset); |
| 489 | gly += StrikeCache.unsafe.getFloat(images[i]+yAdvOffset); |
| 490 | } |
| 491 | gx1 = gx0 + gw; |
| 492 | gy1 = gy0 + gh; |
| 493 | if (bx0 > gx0) bx0 = gx0; |
| 494 | if (by0 > gy0) by0 = gy0; |
| 495 | if (bx1 < gx1) bx1 = gx1; |
| 496 | if (by1 < gy1) by1 = gy1; |
| 497 | } |
| 498 | /* floor is safe and correct because all glyph widths, heights |
| 499 | * and offsets are integers |
| 500 | */ |
| 501 | bounds[0] = (int)Math.floor(bx0); |
| 502 | bounds[1] = (int)Math.floor(by0); |
| 503 | bounds[2] = (int)Math.floor(bx1); |
| 504 | bounds[3] = (int)Math.floor(by1); |
| 505 | } |
| 506 | } |