1 /*
2 * Copyright (c) 2007, 2018, 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.marlin;
27
28 import java.util.Arrays;
29 import sun.java2d.marlin.DTransformingPathConsumer2D.CurveBasicMonotonizer;
30 import sun.java2d.marlin.DTransformingPathConsumer2D.CurveClipSplitter;
31
32 /**
33 * The <code>DDasher</code> class takes a series of linear commands
34 * (<code>moveTo</code>, <code>lineTo</code>, <code>close</code> and
35 * <code>end</code>) and breaks them into smaller segments according to a
36 * dash pattern array and a starting dash phase.
37 *
38 * <p> Issues: in J2Se, a zero length dash segment as drawn as a very
39 * short dash, whereas Pisces does not draw anything. The PostScript
40 * semantics are unclear.
41 *
42 */
43 final class DDasher implements DPathConsumer2D, MarlinConst {
44
45 /* huge circle with radius ~ 2E9 only needs 12 subdivision levels */
46 static final int REC_LIMIT = 16;
47 static final double CURVE_LEN_ERR = MarlinProperties.getCurveLengthError(); // 0.01 initial
48 static final double MIN_T_INC = 1.0d / (1 << REC_LIMIT);
49
50 // More than 24 bits of mantissa means we can no longer accurately
51 // measure the number of times cycled through the dash array so we
52 // punt and override the phase to just be 0 past that point.
53 static final double MAX_CYCLES = 16000000.0d;
54
55 private DPathConsumer2D out;
56 private double[] dash;
57 private int dashLen;
58 private double startPhase;
59 private boolean startDashOn;
60 private int startIdx;
61
62 private boolean starting;
63 private boolean needsMoveTo;
64
65 private int idx;
66 private boolean dashOn;
67 private double phase;
68
69 // The starting point of the path
70 private double sx0, sy0;
71 // the current point
72 private double cx0, cy0;
73
74 // temporary storage for the current curve
75 private final double[] curCurvepts;
76
77 // per-thread renderer context
78 final DRendererContext rdrCtx;
79
80 // flag to recycle dash array copy
81 boolean recycleDashes;
82
83 // We don't emit the first dash right away. If we did, caps would be
84 // drawn on it, but we need joins to be drawn if there's a closePath()
85 // So, we store the path elements that make up the first dash in the
86 // buffer below.
87 private double[] firstSegmentsBuffer; // dynamic array
88 private int firstSegidx;
89
90 // dashes ref (dirty)
91 final DoubleArrayCache.Reference dashes_ref;
92 // firstSegmentsBuffer ref (dirty)
93 final DoubleArrayCache.Reference firstSegmentsBuffer_ref;
94
95 // Bounds of the drawing region, at pixel precision.
96 private double[] clipRect;
97
98 // the outcode of the current point
99 private int cOutCode = 0;
100
101 private boolean subdivide = DO_CLIP_SUBDIVIDER;
102
103 private final LengthIterator li = new LengthIterator();
104
105 private final CurveClipSplitter curveSplitter;
106
107 private double cycleLen;
108 private boolean outside;
109 private double totalSkipLen;
110
111 /**
112 * Constructs a <code>DDasher</code>.
113 * @param rdrCtx per-thread renderer context
114 */
115 DDasher(final DRendererContext rdrCtx) {
116 this.rdrCtx = rdrCtx;
117
118 dashes_ref = rdrCtx.newDirtyDoubleArrayRef(INITIAL_ARRAY); // 1K
119
120 firstSegmentsBuffer_ref = rdrCtx.newDirtyDoubleArrayRef(INITIAL_ARRAY); // 1K
121 firstSegmentsBuffer = firstSegmentsBuffer_ref.initial;
122
123 // we need curCurvepts to be able to contain 2 curves because when
124 // dashing curves, we need to subdivide it
125 curCurvepts = new double[8 * 2];
126
127 this.curveSplitter = rdrCtx.curveClipSplitter;
128 }
129
130 /**
131 * Initialize the <code>DDasher</code>.
132 *
133 * @param out an output <code>DPathConsumer2D</code>.
134 * @param dash an array of <code>double</code>s containing the dash pattern
135 * @param dashLen length of the given dash array
136 * @param phase a <code>double</code> containing the dash phase
137 * @param recycleDashes true to indicate to recycle the given dash array
138 * @return this instance
139 */
140 DDasher init(final DPathConsumer2D out, double[] dash, int dashLen,
141 double phase, boolean recycleDashes)
142 {
143 this.out = out;
144
145 // Normalize so 0 <= phase < dash[0]
146 int sidx = 0;
147 dashOn = true;
148
149 double sum = 0.0d;
150 for (double d : dash) {
151 sum += d;
152 }
153 this.cycleLen = sum;
154
155 double cycles = phase / sum;
156 if (phase < 0.0d) {
157 if (-cycles >= MAX_CYCLES) {
158 phase = 0.0d;
159 } else {
160 int fullcycles = FloatMath.floor_int(-cycles);
161 if ((fullcycles & dash.length & 1) != 0) {
162 dashOn = !dashOn;
163 }
164 phase += fullcycles * sum;
165 while (phase < 0.0d) {
166 if (--sidx < 0) {
167 sidx = dash.length - 1;
168 }
169 phase += dash[sidx];
170 dashOn = !dashOn;
171 }
172 }
173 } else if (phase > 0.0d) {
174 if (cycles >= MAX_CYCLES) {
175 phase = 0.0d;
176 } else {
177 int fullcycles = FloatMath.floor_int(cycles);
178 if ((fullcycles & dash.length & 1) != 0) {
179 dashOn = !dashOn;
180 }
181 phase -= fullcycles * sum;
182 double d;
183 while (phase >= (d = dash[sidx])) {
184 phase -= d;
185 sidx = (sidx + 1) % dash.length;
186 dashOn = !dashOn;
187 }
188 }
189 }
190
191 this.dash = dash;
192 this.dashLen = dashLen;
193 this.phase = phase;
194 this.startPhase = phase;
195 this.startDashOn = dashOn;
196 this.startIdx = sidx;
197 this.starting = true;
198 this.needsMoveTo = false;
199 this.firstSegidx = 0;
200
201 this.recycleDashes = recycleDashes;
202
203 if (rdrCtx.doClip) {
204 this.clipRect = rdrCtx.clipRect;
205 } else {
206 this.clipRect = null;
207 this.cOutCode = 0;
208 }
209 return this; // fluent API
210 }
211
212 /**
213 * Disposes this dasher:
214 * clean up before reusing this instance
215 */
216 void dispose() {
217 if (DO_CLEAN_DIRTY) {
218 // Force zero-fill dirty arrays:
219 Arrays.fill(curCurvepts, 0.0d);
220 }
221 // Return arrays:
222 if (recycleDashes) {
223 dash = dashes_ref.putArray(dash);
224 }
225 firstSegmentsBuffer = firstSegmentsBuffer_ref.putArray(firstSegmentsBuffer);
226 }
227
228 double[] copyDashArray(final float[] dashes) {
229 final int len = dashes.length;
230 final double[] newDashes;
231 if (len <= MarlinConst.INITIAL_ARRAY) {
232 newDashes = dashes_ref.initial;
233 } else {
234 if (DO_STATS) {
235 rdrCtx.stats.stat_array_dasher_dasher.add(len);
236 }
237 newDashes = dashes_ref.getArray(len);
238 }
239 for (int i = 0; i < len; i++) { newDashes[i] = dashes[i]; }
240 return newDashes;
241 }
242
243 @Override
244 public void moveTo(final double x0, final double y0) {
245 if (firstSegidx != 0) {
246 out.moveTo(sx0, sy0);
247 emitFirstSegments();
248 }
249 this.needsMoveTo = true;
250 this.idx = startIdx;
251 this.dashOn = this.startDashOn;
252 this.phase = this.startPhase;
253 this.cx0 = x0;
254 this.cy0 = y0;
255
256 // update starting point:
257 this.sx0 = x0;
258 this.sy0 = y0;
259 this.starting = true;
260
261 if (clipRect != null) {
262 final int outcode = DHelpers.outcode(x0, y0, clipRect);
263 this.cOutCode = outcode;
264 this.outside = false;
265 this.totalSkipLen = 0.0d;
266 }
267 }
268
269 private void emitSeg(double[] buf, int off, int type) {
270 switch (type) {
271 case 8:
272 out.curveTo(buf[off ], buf[off + 1],
273 buf[off + 2], buf[off + 3],
274 buf[off + 4], buf[off + 5]);
275 return;
276 case 6:
277 out.quadTo(buf[off ], buf[off + 1],
278 buf[off + 2], buf[off + 3]);
279 return;
280 case 4:
281 out.lineTo(buf[off], buf[off + 1]);
282 return;
283 default:
284 }
285 }
286
287 private void emitFirstSegments() {
288 final double[] fSegBuf = firstSegmentsBuffer;
289
290 for (int i = 0, len = firstSegidx; i < len; ) {
291 int type = (int)fSegBuf[i];
292 emitSeg(fSegBuf, i + 1, type);
293 i += (type - 1);
294 }
295 firstSegidx = 0;
296 }
297
298 // precondition: pts must be in relative coordinates (relative to x0,y0)
299 private void goTo(final double[] pts, final int off, final int type,
300 final boolean on)
301 {
302 final int index = off + type;
303 final double x = pts[index - 4];
304 final double y = pts[index - 3];
305
306 if (on) {
307 if (starting) {
308 goTo_starting(pts, off, type);
309 } else {
310 if (needsMoveTo) {
311 needsMoveTo = false;
312 out.moveTo(cx0, cy0);
313 }
314 emitSeg(pts, off, type);
315 }
316 } else {
317 if (starting) {
318 // low probability test (hotspot)
319 starting = false;
320 }
321 needsMoveTo = true;
322 }
323 this.cx0 = x;
324 this.cy0 = y;
325 }
326
327 private void goTo_starting(final double[] pts, final int off, final int type) {
328 int len = type - 1; // - 2 + 1
329 int segIdx = firstSegidx;
330 double[] buf = firstSegmentsBuffer;
331
332 if (segIdx + len > buf.length) {
333 if (DO_STATS) {
334 rdrCtx.stats.stat_array_dasher_firstSegmentsBuffer
335 .add(segIdx + len);
336 }
337 firstSegmentsBuffer = buf
338 = firstSegmentsBuffer_ref.widenArray(buf, segIdx,
339 segIdx + len);
340 }
341 buf[segIdx++] = type;
342 len--;
343 // small arraycopy (2, 4 or 6) but with offset:
344 System.arraycopy(pts, off, buf, segIdx, len);
345 firstSegidx = segIdx + len;
346 }
347
348 @Override
349 public void lineTo(final double x1, final double y1) {
350 final int outcode0 = this.cOutCode;
351
352 if (clipRect != null) {
353 final int outcode1 = DHelpers.outcode(x1, y1, clipRect);
354
355 // Should clip
356 final int orCode = (outcode0 | outcode1);
357
358 if (orCode != 0) {
359 final int sideCode = outcode0 & outcode1;
360
361 // basic rejection criteria:
362 if (sideCode == 0) {
363 // ovelap clip:
364 if (subdivide) {
365 // avoid reentrance
366 subdivide = false;
367 // subdivide curve => callback with subdivided parts:
368 boolean ret = curveSplitter.splitLine(cx0, cy0, x1, y1,
369 orCode, this);
370 // reentrance is done:
371 subdivide = true;
372 if (ret) {
373 return;
374 }
375 }
376 // already subdivided so render it
377 } else {
378 this.cOutCode = outcode1;
379 skipLineTo(x1, y1);
380 return;
381 }
382 }
383
384 this.cOutCode = outcode1;
385
386 if (this.outside) {
387 this.outside = false;
388 // Adjust current index, phase & dash:
389 skipLen();
390 }
391 }
392 _lineTo(x1, y1);
393 }
394
395 private void _lineTo(final double x1, final double y1) {
396 final double dx = x1 - cx0;
397 final double dy = y1 - cy0;
398
399 double len = dx * dx + dy * dy;
400 if (len == 0.0d) {
401 return;
402 }
403 len = Math.sqrt(len);
404
405 // The scaling factors needed to get the dx and dy of the
406 // transformed dash segments.
407 final double cx = dx / len;
408 final double cy = dy / len;
409
410 final double[] _curCurvepts = curCurvepts;
411 final double[] _dash = dash;
412 final int _dashLen = this.dashLen;
413
414 int _idx = idx;
415 boolean _dashOn = dashOn;
416 double _phase = phase;
417
418 double leftInThisDashSegment, d;
419
420 while (true) {
421 d = _dash[_idx];
422 leftInThisDashSegment = d - _phase;
423
424 if (len <= leftInThisDashSegment) {
425 _curCurvepts[0] = x1;
426 _curCurvepts[1] = y1;
427
428 goTo(_curCurvepts, 0, 4, _dashOn);
429
430 // Advance phase within current dash segment
431 _phase += len;
432
433 // TODO: compare double values using epsilon:
434 if (len == leftInThisDashSegment) {
435 _phase = 0.0d;
436 _idx = (_idx + 1) % _dashLen;
437 _dashOn = !_dashOn;
438 }
439 break;
440 }
441
442 if (_phase == 0.0d) {
443 _curCurvepts[0] = cx0 + d * cx;
444 _curCurvepts[1] = cy0 + d * cy;
445 } else {
446 _curCurvepts[0] = cx0 + leftInThisDashSegment * cx;
447 _curCurvepts[1] = cy0 + leftInThisDashSegment * cy;
448 }
449
450 goTo(_curCurvepts, 0, 4, _dashOn);
451
452 len -= leftInThisDashSegment;
453 // Advance to next dash segment
454 _idx = (_idx + 1) % _dashLen;
455 _dashOn = !_dashOn;
456 _phase = 0.0d;
457 }
458 // Save local state:
459 idx = _idx;
460 dashOn = _dashOn;
461 phase = _phase;
462 }
463
464 private void skipLineTo(final double x1, final double y1) {
465 final double dx = x1 - cx0;
466 final double dy = y1 - cy0;
467
468 double len = dx * dx + dy * dy;
469 if (len != 0.0d) {
470 len = Math.sqrt(len);
471 }
472
473 // Accumulate skipped length:
474 this.outside = true;
475 this.totalSkipLen += len;
476
477 // Fix initial move:
478 this.needsMoveTo = true;
479 this.starting = false;
480
481 this.cx0 = x1;
482 this.cy0 = y1;
483 }
484
485 public void skipLen() {
486 double len = this.totalSkipLen;
487 this.totalSkipLen = 0.0d;
488
489 final double[] _dash = dash;
490 final int _dashLen = this.dashLen;
491
492 int _idx = idx;
493 boolean _dashOn = dashOn;
494 double _phase = phase;
495
496 // -2 to ensure having 2 iterations of the post-loop
497 // to compensate the remaining phase
498 final long fullcycles = (long)Math.floor(len / cycleLen) - 2L;
499
500 if (fullcycles > 0L) {
501 len -= cycleLen * fullcycles;
502
503 final long iterations = fullcycles * _dashLen;
504 _idx = (int) (iterations + _idx) % _dashLen;
505 _dashOn = (iterations + (_dashOn ? 1L : 0L) & 1L) == 1L;
506 }
507
508 double leftInThisDashSegment, d;
509
510 while (true) {
511 d = _dash[_idx];
512 leftInThisDashSegment = d - _phase;
513
514 if (len <= leftInThisDashSegment) {
515 // Advance phase within current dash segment
516 _phase += len;
517
518 // TODO: compare double values using epsilon:
519 if (len == leftInThisDashSegment) {
520 _phase = 0.0d;
521 _idx = (_idx + 1) % _dashLen;
522 _dashOn = !_dashOn;
523 }
524 break;
525 }
526
527 len -= leftInThisDashSegment;
528 // Advance to next dash segment
529 _idx = (_idx + 1) % _dashLen;
530 _dashOn = !_dashOn;
531 _phase = 0.0d;
532 }
533 // Save local state:
534 idx = _idx;
535 dashOn = _dashOn;
536 phase = _phase;
537 }
538
539 // preconditions: curCurvepts must be an array of length at least 2 * type,
540 // that contains the curve we want to dash in the first type elements
541 private void somethingTo(final int type) {
542 final double[] _curCurvepts = curCurvepts;
543 if (pointCurve(_curCurvepts, type)) {
544 return;
545 }
546 final LengthIterator _li = li;
547 final double[] _dash = dash;
548 final int _dashLen = this.dashLen;
549
550 _li.initializeIterationOnCurve(_curCurvepts, type);
551
552 int _idx = idx;
553 boolean _dashOn = dashOn;
554 double _phase = phase;
555
556 // initially the current curve is at curCurvepts[0...type]
557 int curCurveoff = 0;
558 double prevT = 0.0d;
559 double t;
560 double leftInThisDashSegment = _dash[_idx] - _phase;
561
562 while ((t = _li.next(leftInThisDashSegment)) < 1.0d) {
563 if (t != 0.0d) {
564 DHelpers.subdivideAt((t - prevT) / (1.0d - prevT),
565 _curCurvepts, curCurveoff,
566 _curCurvepts, 0, type);
567 prevT = t;
568 goTo(_curCurvepts, 2, type, _dashOn);
569 curCurveoff = type;
570 }
571 // Advance to next dash segment
572 _idx = (_idx + 1) % _dashLen;
573 _dashOn = !_dashOn;
574 _phase = 0.0d;
575 leftInThisDashSegment = _dash[_idx];
576 }
577
578 goTo(_curCurvepts, curCurveoff + 2, type, _dashOn);
579
580 _phase += _li.lastSegLen();
581 if (_phase >= _dash[_idx]) {
582 _phase = 0.0d;
583 _idx = (_idx + 1) % _dashLen;
584 _dashOn = !_dashOn;
585 }
586 // Save local state:
587 idx = _idx;
588 dashOn = _dashOn;
589 phase = _phase;
590
591 // reset LengthIterator:
592 _li.reset();
593 }
594
595 private void skipSomethingTo(final int type) {
596 final double[] _curCurvepts = curCurvepts;
597 if (pointCurve(_curCurvepts, type)) {
598 return;
599 }
600 final LengthIterator _li = li;
601
602 _li.initializeIterationOnCurve(_curCurvepts, type);
603
604 // In contrary to somethingTo(),
605 // just estimate properly the curve length:
606 final double len = _li.totalLength();
607
608 // Accumulate skipped length:
609 this.outside = true;
610 this.totalSkipLen += len;
611
612 // Fix initial move:
613 this.needsMoveTo = true;
614 this.starting = false;
615 }
616
617 private static boolean pointCurve(final double[] curve, final int type) {
618 for (int i = 2; i < type; i++) {
619 if (curve[i] != curve[i-2]) {
620 return false;
621 }
622 }
623 return true;
624 }
625
626 // Objects of this class are used to iterate through curves. They return
627 // t values where the left side of the curve has a specified length.
628 // It does this by subdividing the input curve until a certain error
629 // condition has been met. A recursive subdivision procedure would
630 // return as many as 1<<limit curves, but this is an iterator and we
631 // don't need all the curves all at once, so what we carry out a
632 // lazy inorder traversal of the recursion tree (meaning we only move
633 // through the tree when we need the next subdivided curve). This saves
634 // us a lot of memory because at any one time we only need to store
635 // limit+1 curves - one for each level of the tree + 1.
636 // NOTE: the way we do things here is not enough to traverse a general
637 // tree; however, the trees we are interested in have the property that
638 // every non leaf node has exactly 2 children
639 static final class LengthIterator {
640 // Holds the curves at various levels of the recursion. The root
641 // (i.e. the original curve) is at recCurveStack[0] (but then it
642 // gets subdivided, the left half is put at 1, so most of the time
643 // only the right half of the original curve is at 0)
644 private final double[][] recCurveStack; // dirty
645 // sidesRight[i] indicates whether the node at level i+1 in the path from
646 // the root to the current leaf is a left or right child of its parent.
647 private final boolean[] sidesRight; // dirty
648 private int curveType;
649 // lastT and nextT delimit the current leaf.
650 private double nextT;
651 private double lenAtNextT;
652 private double lastT;
653 private double lenAtLastT;
654 private double lenAtLastSplit;
655 private double lastSegLen;
656 // the current level in the recursion tree. 0 is the root. limit
657 // is the deepest possible leaf.
658 private int recLevel;
659 private boolean done;
660
661 // the lengths of the lines of the control polygon. Only its first
662 // curveType/2 - 1 elements are valid. This is an optimization. See
663 // next() for more detail.
664 private final double[] curLeafCtrlPolyLengths = new double[3];
665
666 LengthIterator() {
667 this.recCurveStack = new double[REC_LIMIT + 1][8];
668 this.sidesRight = new boolean[REC_LIMIT];
669 // if any methods are called without first initializing this object
670 // on a curve, we want it to fail ASAP.
671 this.nextT = Double.MAX_VALUE;
672 this.lenAtNextT = Double.MAX_VALUE;
673 this.lenAtLastSplit = Double.MIN_VALUE;
674 this.recLevel = Integer.MIN_VALUE;
675 this.lastSegLen = Double.MAX_VALUE;
676 this.done = true;
677 }
678
679 /**
680 * Reset this LengthIterator.
681 */
682 void reset() {
683 // keep data dirty
684 // as it appears not useful to reset data:
685 if (DO_CLEAN_DIRTY) {
686 final int recLimit = recCurveStack.length - 1;
687 for (int i = recLimit; i >= 0; i--) {
688 Arrays.fill(recCurveStack[i], 0.0d);
689 }
690 Arrays.fill(sidesRight, false);
691 Arrays.fill(curLeafCtrlPolyLengths, 0.0d);
692 Arrays.fill(nextRoots, 0.0d);
693 Arrays.fill(flatLeafCoefCache, 0.0d);
694 flatLeafCoefCache[2] = -1.0d;
695 }
696 }
697
698 void initializeIterationOnCurve(final double[] pts, final int type) {
699 // optimize arraycopy (8 values faster than 6 = type):
700 System.arraycopy(pts, 0, recCurveStack[0], 0, 8);
701 this.curveType = type;
702 this.recLevel = 0;
703 this.lastT = 0.0d;
704 this.lenAtLastT = 0.0d;
705 this.nextT = 0.0d;
706 this.lenAtNextT = 0.0d;
707 goLeft(); // initializes nextT and lenAtNextT properly
708 this.lenAtLastSplit = 0.0d;
709 if (recLevel > 0) {
710 this.sidesRight[0] = false;
711 this.done = false;
712 } else {
713 // the root of the tree is a leaf so we're done.
714 this.sidesRight[0] = true;
715 this.done = true;
716 }
717 this.lastSegLen = 0.0d;
718 }
719
720 // 0 == false, 1 == true, -1 == invalid cached value.
721 private int cachedHaveLowAcceleration = -1;
722
723 private boolean haveLowAcceleration(final double err) {
724 if (cachedHaveLowAcceleration == -1) {
725 final double len1 = curLeafCtrlPolyLengths[0];
726 final double len2 = curLeafCtrlPolyLengths[1];
727 // the test below is equivalent to !within(len1/len2, 1, err).
728 // It is using a multiplication instead of a division, so it
729 // should be a bit faster.
730 if (!DHelpers.within(len1, len2, err * len2)) {
731 cachedHaveLowAcceleration = 0;
732 return false;
733 }
734 if (curveType == 8) {
735 final double len3 = curLeafCtrlPolyLengths[2];
736 // if len1 is close to 2 and 2 is close to 3, that probably
737 // means 1 is close to 3 so the second part of this test might
738 // not be needed, but it doesn't hurt to include it.
739 final double errLen3 = err * len3;
740 if (!(DHelpers.within(len2, len3, errLen3) &&
741 DHelpers.within(len1, len3, errLen3))) {
742 cachedHaveLowAcceleration = 0;
743 return false;
744 }
745 }
746 cachedHaveLowAcceleration = 1;
747 return true;
748 }
749
750 return (cachedHaveLowAcceleration == 1);
751 }
752
753 // we want to avoid allocations/gc so we keep this array so we
754 // can put roots in it,
755 private final double[] nextRoots = new double[4];
756
757 // caches the coefficients of the current leaf in its flattened
758 // form (see inside next() for what that means). The cache is
759 // invalid when it's third element is negative, since in any
760 // valid flattened curve, this would be >= 0.
761 private final double[] flatLeafCoefCache = new double[]{0.0d, 0.0d, -1.0d, 0.0d};
762
763 // returns the t value where the remaining curve should be split in
764 // order for the left subdivided curve to have length len. If len
765 // is >= than the length of the uniterated curve, it returns 1.
766 double next(final double len) {
767 final double targetLength = lenAtLastSplit + len;
768 while (lenAtNextT < targetLength) {
769 if (done) {
770 lastSegLen = lenAtNextT - lenAtLastSplit;
771 return 1.0d;
772 }
773 goToNextLeaf();
774 }
775 lenAtLastSplit = targetLength;
776 final double leaflen = lenAtNextT - lenAtLastT;
777 double t = (targetLength - lenAtLastT) / leaflen;
778
779 // cubicRootsInAB is a fairly expensive call, so we just don't do it
780 // if the acceleration in this section of the curve is small enough.
781 if (!haveLowAcceleration(0.05d)) {
782 // We flatten the current leaf along the x axis, so that we're
783 // left with a, b, c which define a 1D Bezier curve. We then
784 // solve this to get the parameter of the original leaf that
785 // gives us the desired length.
786 final double[] _flatLeafCoefCache = flatLeafCoefCache;
787
788 if (_flatLeafCoefCache[2] < 0.0d) {
789 double x = curLeafCtrlPolyLengths[0],
790 y = x + curLeafCtrlPolyLengths[1];
791 if (curveType == 8) {
792 double z = y + curLeafCtrlPolyLengths[2];
793 _flatLeafCoefCache[0] = 3.0d * (x - y) + z;
794 _flatLeafCoefCache[1] = 3.0d * (y - 2.0d * x);
795 _flatLeafCoefCache[2] = 3.0d * x;
796 _flatLeafCoefCache[3] = -z;
797 } else if (curveType == 6) {
798 _flatLeafCoefCache[0] = 0.0d;
799 _flatLeafCoefCache[1] = y - 2.0d * x;
800 _flatLeafCoefCache[2] = 2.0d * x;
801 _flatLeafCoefCache[3] = -y;
802 }
803 }
804 double a = _flatLeafCoefCache[0];
805 double b = _flatLeafCoefCache[1];
806 double c = _flatLeafCoefCache[2];
807 double d = t * _flatLeafCoefCache[3];
808
809 // we use cubicRootsInAB here, because we want only roots in 0, 1,
810 // and our quadratic root finder doesn't filter, so it's just a
811 // matter of convenience.
812 final int n = DHelpers.cubicRootsInAB(a, b, c, d, nextRoots, 0, 0.0d, 1.0d);
813 if (n == 1 && !Double.isNaN(nextRoots[0])) {
814 t = nextRoots[0];
815 }
816 }
817 // t is relative to the current leaf, so we must make it a valid parameter
818 // of the original curve.
819 t = t * (nextT - lastT) + lastT;
820 if (t >= 1.0d) {
821 t = 1.0d;
822 done = true;
823 }
824 // even if done = true, if we're here, that means targetLength
825 // is equal to, or very, very close to the total length of the
826 // curve, so lastSegLen won't be too high. In cases where len
827 // overshoots the curve, this method will exit in the while
828 // loop, and lastSegLen will still be set to the right value.
829 lastSegLen = len;
830 return t;
831 }
832
833 double totalLength() {
834 while (!done) {
835 goToNextLeaf();
836 }
837 // reset LengthIterator:
838 reset();
839
840 return lenAtNextT;
841 }
842
843 double lastSegLen() {
844 return lastSegLen;
845 }
846
847 // go to the next leaf (in an inorder traversal) in the recursion tree
848 // preconditions: must be on a leaf, and that leaf must not be the root.
849 private void goToNextLeaf() {
850 // We must go to the first ancestor node that has an unvisited
851 // right child.
852 final boolean[] _sides = sidesRight;
853 int _recLevel = recLevel;
854 _recLevel--;
855
856 while(_sides[_recLevel]) {
857 if (_recLevel == 0) {
858 recLevel = 0;
859 done = true;
860 return;
861 }
862 _recLevel--;
863 }
864
865 _sides[_recLevel] = true;
866 // optimize arraycopy (8 values faster than 6 = type):
867 System.arraycopy(recCurveStack[_recLevel++], 0,
868 recCurveStack[_recLevel], 0, 8);
869 recLevel = _recLevel;
870 goLeft();
871 }
872
873 // go to the leftmost node from the current node. Return its length.
874 private void goLeft() {
875 final double len = onLeaf();
876 if (len >= 0.0d) {
877 lastT = nextT;
878 lenAtLastT = lenAtNextT;
879 nextT += (1 << (REC_LIMIT - recLevel)) * MIN_T_INC;
880 lenAtNextT += len;
881 // invalidate caches
882 flatLeafCoefCache[2] = -1.0d;
883 cachedHaveLowAcceleration = -1;
884 } else {
885 DHelpers.subdivide(recCurveStack[recLevel],
886 recCurveStack[recLevel + 1],
887 recCurveStack[recLevel], curveType);
888
889 sidesRight[recLevel] = false;
890 recLevel++;
891 goLeft();
892 }
893 }
894
895 // this is a bit of a hack. It returns -1 if we're not on a leaf, and
896 // the length of the leaf if we are on a leaf.
897 private double onLeaf() {
898 final double[] curve = recCurveStack[recLevel];
899 final int _curveType = curveType;
900 double polyLen = 0.0d;
901
902 double x0 = curve[0], y0 = curve[1];
903 for (int i = 2; i < _curveType; i += 2) {
904 final double x1 = curve[i], y1 = curve[i + 1];
905 final double len = DHelpers.linelen(x0, y0, x1, y1);
906 polyLen += len;
907 curLeafCtrlPolyLengths[(i >> 1) - 1] = len;
908 x0 = x1;
909 y0 = y1;
910 }
911
912 final double lineLen = DHelpers.linelen(curve[0], curve[1], x0, y0);
913
914 if ((polyLen - lineLen) < CURVE_LEN_ERR || recLevel == REC_LIMIT) {
915 return (polyLen + lineLen) / 2.0d;
916 }
917 return -1.0d;
918 }
919 }
920
921 @Override
922 public void curveTo(final double x1, final double y1,
923 final double x2, final double y2,
924 final double x3, final double y3)
925 {
926 final int outcode0 = this.cOutCode;
927
928 if (clipRect != null) {
929 final int outcode1 = DHelpers.outcode(x1, y1, clipRect);
930 final int outcode2 = DHelpers.outcode(x2, y2, clipRect);
931 final int outcode3 = DHelpers.outcode(x3, y3, clipRect);
932
933 // Should clip
934 final int orCode = (outcode0 | outcode1 | outcode2 | outcode3);
935 if (orCode != 0) {
936 final int sideCode = outcode0 & outcode1 & outcode2 & outcode3;
937
938 // basic rejection criteria:
939 if (sideCode == 0) {
940 // ovelap clip:
941 if (subdivide) {
942 // avoid reentrance
943 subdivide = false;
944 // subdivide curve => callback with subdivided parts:
945 boolean ret = curveSplitter.splitCurve(cx0, cy0, x1, y1, x2, y2, x3, y3,
946 orCode, this);
947 // reentrance is done:
948 subdivide = true;
949 if (ret) {
950 return;
951 }
952 }
953 // already subdivided so render it
954 } else {
955 this.cOutCode = outcode3;
956 skipCurveTo(x1, y1, x2, y2, x3, y3);
957 return;
958 }
959 }
960
961 this.cOutCode = outcode3;
962
963 if (this.outside) {
964 this.outside = false;
965 // Adjust current index, phase & dash:
966 skipLen();
967 }
968 }
969 _curveTo(x1, y1, x2, y2, x3, y3);
970 }
971
972 private void _curveTo(final double x1, final double y1,
973 final double x2, final double y2,
974 final double x3, final double y3)
975 {
976 final double[] _curCurvepts = curCurvepts;
977
978 // monotonize curve:
979 final CurveBasicMonotonizer monotonizer
980 = rdrCtx.monotonizer.curve(cx0, cy0, x1, y1, x2, y2, x3, y3);
981
982 final int nSplits = monotonizer.nbSplits;
983 final double[] mid = monotonizer.middle;
984
985 for (int i = 0, off = 0; i <= nSplits; i++, off += 6) {
986 // optimize arraycopy (8 values faster than 6 = type):
987 System.arraycopy(mid, off, _curCurvepts, 0, 8);
988
989 somethingTo(8);
990 }
991 }
992
993 private void skipCurveTo(final double x1, final double y1,
994 final double x2, final double y2,
995 final double x3, final double y3)
996 {
997 final double[] _curCurvepts = curCurvepts;
998 _curCurvepts[0] = cx0; _curCurvepts[1] = cy0;
999 _curCurvepts[2] = x1; _curCurvepts[3] = y1;
1000 _curCurvepts[4] = x2; _curCurvepts[5] = y2;
1001 _curCurvepts[6] = x3; _curCurvepts[7] = y3;
1002
1003 skipSomethingTo(8);
1004
1005 this.cx0 = x3;
1006 this.cy0 = y3;
1007 }
1008
1009 @Override
1010 public void quadTo(final double x1, final double y1,
1011 final double x2, final double y2)
1012 {
1013 final int outcode0 = this.cOutCode;
1014
1015 if (clipRect != null) {
1016 final int outcode1 = DHelpers.outcode(x1, y1, clipRect);
1017 final int outcode2 = DHelpers.outcode(x2, y2, clipRect);
1018
1019 // Should clip
1020 final int orCode = (outcode0 | outcode1 | outcode2);
1021 if (orCode != 0) {
1022 final int sideCode = outcode0 & outcode1 & outcode2;
1023
1024 // basic rejection criteria:
1025 if (sideCode == 0) {
1026 // ovelap clip:
1027 if (subdivide) {
1028 // avoid reentrance
1029 subdivide = false;
1030 // subdivide curve => call lineTo() with subdivided curves:
1031 boolean ret = curveSplitter.splitQuad(cx0, cy0, x1, y1,
1032 x2, y2, orCode, this);
1033 // reentrance is done:
1034 subdivide = true;
1035 if (ret) {
1036 return;
1037 }
1038 }
1039 // already subdivided so render it
1040 } else {
1041 this.cOutCode = outcode2;
1042 skipQuadTo(x1, y1, x2, y2);
1043 return;
1044 }
1045 }
1046
1047 this.cOutCode = outcode2;
1048
1049 if (this.outside) {
1050 this.outside = false;
1051 // Adjust current index, phase & dash:
1052 skipLen();
1053 }
1054 }
1055 _quadTo(x1, y1, x2, y2);
1056 }
1057
1058 private void _quadTo(final double x1, final double y1,
1059 final double x2, final double y2)
1060 {
1061 final double[] _curCurvepts = curCurvepts;
1062
1063 // monotonize quad:
1064 final CurveBasicMonotonizer monotonizer
1065 = rdrCtx.monotonizer.quad(cx0, cy0, x1, y1, x2, y2);
1066
1067 final int nSplits = monotonizer.nbSplits;
1068 final double[] mid = monotonizer.middle;
1069
1070 for (int i = 0, off = 0; i <= nSplits; i++, off += 4) {
1071 // optimize arraycopy (8 values faster than 6 = type):
1072 System.arraycopy(mid, off, _curCurvepts, 0, 8);
1073
1074 somethingTo(6);
1075 }
1076 }
1077
1078 private void skipQuadTo(final double x1, final double y1,
1079 final double x2, final double y2)
1080 {
1081 final double[] _curCurvepts = curCurvepts;
1082 _curCurvepts[0] = cx0; _curCurvepts[1] = cy0;
1083 _curCurvepts[2] = x1; _curCurvepts[3] = y1;
1084 _curCurvepts[4] = x2; _curCurvepts[5] = y2;
1085
1086 skipSomethingTo(6);
1087
1088 this.cx0 = x2;
1089 this.cy0 = y2;
1090 }
1091
1092 @Override
1093 public void closePath() {
1094 if (cx0 != sx0 || cy0 != sy0) {
1095 lineTo(sx0, sy0);
1096 }
1097 if (firstSegidx != 0) {
1098 if (!dashOn || needsMoveTo) {
1099 out.moveTo(sx0, sy0);
1100 }
1101 emitFirstSegments();
1102 }
1103 moveTo(sx0, sy0);
1104 }
1105
1106 @Override
1107 public void pathDone() {
1108 if (firstSegidx != 0) {
1109 out.moveTo(sx0, sy0);
1110 emitFirstSegments();
1111 }
1112 out.pathDone();
1113
1114 // Dispose this instance:
1115 dispose();
1116 }
1117
1118 @Override
1119 public long getNativeConsumer() {
1120 throw new InternalError("DDasher does not use a native consumer");
1121 }
1122 }
1123