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My first initial commit with all of mine experimental changes.

Dmitry Kabak (userdima committed 13 years ago

Commit d37b88d1 parent 3f5b46618352 files · +2598093 −-8690Browse files

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1+/*
2+ * Copyright (c) 2007, 2011, 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.pisces;
27+
28+import java.util.Arrays;
29+import java.util.Iterator;
30+import static java.lang.Math.ulp;
31+import static java.lang.Math.sqrt;
32+
33+import sun.awt.geom.PathConsumer2D;
34+
35+// TODO: some of the arithmetic here is too verbose and prone to hard to
36+// debug typos. We should consider making a small Point/Vector class that
37+// has methods like plus(Point), minus(Point), dot(Point), cross(Point)and such
38+final class Stroker implements PathConsumer2D {
39+
40+ private static final int MOVE_TO = 0;
41+ private static final int DRAWING_OP_TO = 1; // ie. curve, line, or quad
42+ private static final int CLOSE = 2;
43+
44+ /**
45+ * Constant value for join style.
46+ */
47+ public static final int JOIN_MITER = 0;
48+
49+ /**
50+ * Constant value for join style.
51+ */
52+ public static final int JOIN_ROUND = 1;
53+
54+ /**
55+ * Constant value for join style.
56+ */
57+ public static final int JOIN_BEVEL = 2;
58+
59+ /**
60+ * Constant value for end cap style.
61+ */
62+ public static final int CAP_BUTT = 0;
63+
64+ /**
65+ * Constant value for end cap style.
66+ */
67+ public static final int CAP_ROUND = 1;
68+
69+ /**
70+ * Constant value for end cap style.
71+ */
72+ public static final int CAP_SQUARE = 2;
73+
74+ private final PathConsumer2D out;
75+
76+ private final int capStyle;
77+ private final int joinStyle;
78+
79+ private final float lineWidth2;
80+
81+ private final float[][] offset = new float[3][2];
82+ private final float[] miter = new float[2];
83+ private final float miterLimitSq;
84+
85+ private int prev;
86+
87+ // The starting point of the path, and the slope there.
88+ private float sx0, sy0, sdx, sdy;
89+ // the current point and the slope there.
90+ private float cx0, cy0, cdx, cdy; // c stands for current
91+ // vectors that when added to (sx0,sy0) and (cx0,cy0) respectively yield the
92+ // first and last points on the left parallel path. Since this path is
93+ // parallel, it's slope at any point is parallel to the slope of the
94+ // original path (thought they may have different directions), so these
95+ // could be computed from sdx,sdy and cdx,cdy (and vice versa), but that
96+ // would be error prone and hard to read, so we keep these anyway.
97+ private float smx, smy, cmx, cmy;
98+
99+ private final PolyStack reverse = new PolyStack();
100+
101+ /**
102+ * Constructs a <code>Stroker</code>.
103+ *
104+ * @param pc2d an output <code>PathConsumer2D</code>.
105+ * @param lineWidth the desired line width in pixels
106+ * @param capStyle the desired end cap style, one of
107+ * <code>CAP_BUTT</code>, <code>CAP_ROUND</code> or
108+ * <code>CAP_SQUARE</code>.
109+ * @param joinStyle the desired line join style, one of
110+ * <code>JOIN_MITER</code>, <code>JOIN_ROUND</code> or
111+ * <code>JOIN_BEVEL</code>.
112+ * @param miterLimit the desired miter limit
113+ */
114+ public Stroker(PathConsumer2D pc2d,
115+ float lineWidth,
116+ int capStyle,
117+ int joinStyle,
118+ float miterLimit)
119+ {
120+ this.out = pc2d;
121+
122+ this.lineWidth2 = lineWidth / 2;
123+ this.capStyle = capStyle;
124+ this.joinStyle = joinStyle;
125+
126+ float limit = miterLimit * lineWidth2;
127+ this.miterLimitSq = limit*limit;
128+
129+ this.prev = CLOSE;
130+ }
131+
132+ private static void computeOffset(final float lx, final float ly,
133+ final float w, final float[] m)
134+ {
135+ final float len = (float) sqrt(lx*lx + ly*ly);
136+ if (len == 0) {
137+ m[0] = m[1] = 0;
138+ } else {
139+ m[0] = (ly * w)/len;
140+ m[1] = -(lx * w)/len;
141+ }
142+ }
143+
144+ // Returns true if the vectors (dx1, dy1) and (dx2, dy2) are
145+ // clockwise (if dx1,dy1 needs to be rotated clockwise to close
146+ // the smallest angle between it and dx2,dy2).
147+ // This is equivalent to detecting whether a point q is on the right side
148+ // of a line passing through points p1, p2 where p2 = p1+(dx1,dy1) and
149+ // q = p2+(dx2,dy2), which is the same as saying p1, p2, q are in a
150+ // clockwise order.
151+ // NOTE: "clockwise" here assumes coordinates with 0,0 at the bottom left.
152+ private static boolean isCW(final float dx1, final float dy1,
153+ final float dx2, final float dy2)
154+ {
155+ return dx1 * dy2 <= dy1 * dx2;
156+ }
157+
158+ // pisces used to use fixed point arithmetic with 16 decimal digits. I
159+ // didn't want to change the values of the constant below when I converted
160+ // it to floating point, so that's why the divisions by 2^16 are there.
161+ private static final float ROUND_JOIN_THRESHOLD = 1000/65536f;
162+
163+ private void drawRoundJoin(float x, float y,
164+ float omx, float omy, float mx, float my,
165+ boolean rev,
166+ float threshold)
167+ {
168+ if ((omx == 0 && omy == 0) || (mx == 0 && my == 0)) {
169+ return;
170+ }
171+
172+ float domx = omx - mx;
173+ float domy = omy - my;
174+ float len = domx*domx + domy*domy;
175+ if (len < threshold) {
176+ return;
177+ }
178+
179+ if (rev) {
180+ omx = -omx;
181+ omy = -omy;
182+ mx = -mx;
183+ my = -my;
184+ }
185+ drawRoundJoin(x, y, omx, omy, mx, my, rev);
186+ }
187+
188+ private void drawRoundJoin(float cx, float cy,
189+ float omx, float omy,
190+ float mx, float my,
191+ boolean rev)
192+ {
193+ // The sign of the dot product of mx,my and omx,omy is equal to the
194+ // the sign of the cosine of ext
195+ // (ext is the angle between omx,omy and mx,my).
196+ double cosext = omx * mx + omy * my;
197+ // If it is >=0, we know that abs(ext) is <= 90 degrees, so we only
198+ // need 1 curve to approximate the circle section that joins omx,omy
199+ // and mx,my.
200+ final int numCurves = cosext >= 0 ? 1 : 2;
201+
202+ switch (numCurves) {
203+ case 1:
204+ drawBezApproxForArc(cx, cy, omx, omy, mx, my, rev);
205+ break;
206+ case 2:
207+ // we need to split the arc into 2 arcs spanning the same angle.
208+ // The point we want will be one of the 2 intersections of the
209+ // perpendicular bisector of the chord (omx,omy)->(mx,my) and the
210+ // circle. We could find this by scaling the vector
211+ // (omx+mx, omy+my)/2 so that it has length=lineWidth2 (and thus lies
212+ // on the circle), but that can have numerical problems when the angle
213+ // between omx,omy and mx,my is close to 180 degrees. So we compute a
214+ // normal of (omx,omy)-(mx,my). This will be the direction of the
215+ // perpendicular bisector. To get one of the intersections, we just scale
216+ // this vector that its length is lineWidth2 (this works because the
217+ // perpendicular bisector goes through the origin). This scaling doesn't
218+ // have numerical problems because we know that lineWidth2 divided by
219+ // this normal's length is at least 0.5 and at most sqrt(2)/2 (because
220+ // we know the angle of the arc is > 90 degrees).
221+ float nx = my - omy, ny = omx - mx;
222+ float nlen = (float) sqrt(nx*nx + ny*ny);
223+ float scale = lineWidth2/nlen;
224+ float mmx = nx * scale, mmy = ny * scale;
225+
226+ // if (isCW(omx, omy, mx, my) != isCW(mmx, mmy, mx, my)) then we've
227+ // computed the wrong intersection so we get the other one.
228+ // The test above is equivalent to if (rev).
229+ if (rev) {
230+ mmx = -mmx;
231+ mmy = -mmy;
232+ }
233+ drawBezApproxForArc(cx, cy, omx, omy, mmx, mmy, rev);
234+ drawBezApproxForArc(cx, cy, mmx, mmy, mx, my, rev);
235+ break;
236+ }
237+ }
238+
239+ // the input arc defined by omx,omy and mx,my must span <= 90 degrees.
240+ private void drawBezApproxForArc(final float cx, final float cy,
241+ final float omx, final float omy,
242+ final float mx, final float my,
243+ boolean rev)
244+ {
245+ float cosext2 = (omx * mx + omy * my) / (2 * lineWidth2 * lineWidth2);
246+ // cv is the length of P1-P0 and P2-P3 divided by the radius of the arc
247+ // (so, cv assumes the arc has radius 1). P0, P1, P2, P3 are the points that
248+ // define the bezier curve we're computing.
249+ // It is computed using the constraints that P1-P0 and P3-P2 are parallel
250+ // to the arc tangents at the endpoints, and that |P1-P0|=|P3-P2|.
251+ float cv = (float) ((4.0 / 3.0) * sqrt(0.5-cosext2) /
252+ (1.0 + sqrt(cosext2+0.5)));
253+ // if clockwise, we need to negate cv.
254+ if (rev) { // rev is equivalent to isCW(omx, omy, mx, my)
255+ cv = -cv;
256+ }
257+ final float x1 = cx + omx;
258+ final float y1 = cy + omy;
259+ final float x2 = x1 - cv * omy;
260+ final float y2 = y1 + cv * omx;
261+
262+ final float x4 = cx + mx;
263+ final float y4 = cy + my;
264+ final float x3 = x4 + cv * my;
265+ final float y3 = y4 - cv * mx;
266+
267+ emitCurveTo(x1, y1, x2, y2, x3, y3, x4, y4, rev);
268+ }
269+
270+ private void drawRoundCap(float cx, float cy, float mx, float my) {
271+ final float C = 0.5522847498307933f;
272+ // the first and second arguments of the following two calls
273+ // are really will be ignored by emitCurveTo (because of the false),
274+ // but we put them in anyway, as opposed to just giving it 4 zeroes,
275+ // because it's just 4 additions and it's not good to rely on this
276+ // sort of assumption (right now it's true, but that may change).
277+ emitCurveTo(cx+mx, cy+my,
278+ cx+mx-C*my, cy+my+C*mx,
279+ cx-my+C*mx, cy+mx+C*my,
280+ cx-my, cy+mx,
281+ false);
282+ emitCurveTo(cx-my, cy+mx,
283+ cx-my-C*mx, cy+mx-C*my,
284+ cx-mx-C*my, cy-my+C*mx,
285+ cx-mx, cy-my,
286+ false);
287+ }
288+
289+ // Put the intersection point of the lines (x0, y0) -> (x1, y1)
290+ // and (x0p, y0p) -> (x1p, y1p) in m[off] and m[off+1].
291+ // If the lines are parallel, it will put a non finite number in m.
292+ private void computeIntersection(final float x0, final float y0,
293+ final float x1, final float y1,
294+ final float x0p, final float y0p,
295+ final float x1p, final float y1p,
296+ final float[] m, int off)
297+ {
298+ float x10 = x1 - x0;
299+ float y10 = y1 - y0;
300+ float x10p = x1p - x0p;
301+ float y10p = y1p - y0p;
302+
303+ float den = x10*y10p - x10p*y10;
304+ float t = x10p*(y0-y0p) - y10p*(x0-x0p);
305+ t /= den;
306+ m[off++] = x0 + t*x10;
307+ m[off] = y0 + t*y10;
308+ }
309+
310+ private void drawMiter(final float pdx, final float pdy,
311+ final float x0, final float y0,
312+ final float dx, final float dy,
313+ float omx, float omy, float mx, float my,
314+ boolean rev)
315+ {
316+ if ((mx == omx && my == omy) ||
317+ (pdx == 0 && pdy == 0) ||
318+ (dx == 0 && dy == 0))
319+ {
320+ return;
321+ }
322+
323+ if (rev) {
324+ omx = -omx;
325+ omy = -omy;
326+ mx = -mx;
327+ my = -my;
328+ }
329+
330+ computeIntersection((x0 - pdx) + omx, (y0 - pdy) + omy, x0 + omx, y0 + omy,
331+ (dx + x0) + mx, (dy + y0) + my, x0 + mx, y0 + my,
332+ miter, 0);
333+
334+ float lenSq = (miter[0]-x0)*(miter[0]-x0) + (miter[1]-y0)*(miter[1]-y0);
335+
336+ // If the lines are parallel, lenSq will be either NaN or +inf
337+ // (actually, I'm not sure if the latter is possible. The important
338+ // thing is that -inf is not possible, because lenSq is a square).
339+ // For both of those values, the comparison below will fail and
340+ // no miter will be drawn, which is correct.
341+ if (lenSq < miterLimitSq) {
342+ emitLineTo(miter[0], miter[1], rev);
343+ }
344+ }
345+
346+ public void moveTo(float x0, float y0) {
347+ if (prev == DRAWING_OP_TO) {
348+ finish();
349+ }
350+ this.sx0 = this.cx0 = x0;
351+ this.sy0 = this.cy0 = y0;
352+ this.cdx = this.sdx = 1;
353+ this.cdy = this.sdy = 0;
354+ this.prev = MOVE_TO;
355+ }
356+
357+ public void lineTo(float x1, float y1) {
358+ float dx = x1 - cx0;
359+ float dy = y1 - cy0;
360+ if (dx == 0f && dy == 0f) {
361+ dx = 1;
362+ }
363+ computeOffset(dx, dy, lineWidth2, offset[0]);
364+ float mx = offset[0][0];
365+ float my = offset[0][1];
366+
367+ drawJoin(cdx, cdy, cx0, cy0, dx, dy, cmx, cmy, mx, my);
368+
369+ emitLineTo(cx0 + mx, cy0 + my);
370+ emitLineTo(x1 + mx, y1 + my);
371+
372+ emitLineTo(cx0 - mx, cy0 - my, true);
373+ emitLineTo(x1 - mx, y1 - my, true);
374+
375+ this.cmx = mx;
376+ this.cmy = my;
377+ this.cdx = dx;
378+ this.cdy = dy;
379+ this.cx0 = x1;
380+ this.cy0 = y1;
381+ this.prev = DRAWING_OP_TO;
382+ }
383+
384+ public void closePath() {
385+ if (prev != DRAWING_OP_TO) {
386+ if (prev == CLOSE) {
387+ return;
388+ }
389+ emitMoveTo(cx0, cy0 - lineWidth2);
390+ this.cmx = this.smx = 0;
391+ this.cmy = this.smy = -lineWidth2;
392+ this.cdx = this.sdx = 1;
393+ this.cdy = this.sdy = 0;
394+ finish();
395+ return;
396+ }
397+
398+ if (cx0 != sx0 || cy0 != sy0) {
399+ lineTo(sx0, sy0);
400+ }
401+
402+ drawJoin(cdx, cdy, cx0, cy0, sdx, sdy, cmx, cmy, smx, smy);
403+
404+ emitLineTo(sx0 + smx, sy0 + smy);
405+
406+ emitMoveTo(sx0 - smx, sy0 - smy);
407+ emitReverse();
408+
409+ this.prev = CLOSE;
410+ emitClose();
411+ }
412+
413+ private void emitReverse() {
414+ while(!reverse.isEmpty()) {
415+ reverse.pop(out);
416+ }
417+ }
418+
419+ public void pathDone() {
420+ if (prev == DRAWING_OP_TO) {
421+ finish();
422+ }
423+
424+ out.pathDone();
425+ // this shouldn't matter since this object won't be used
426+ // after the call to this method.
427+ this.prev = CLOSE;
428+ }
429+
430+ private void finish() {
431+ if (capStyle == CAP_ROUND) {
432+ drawRoundCap(cx0, cy0, cmx, cmy);
433+ } else if (capStyle == CAP_SQUARE) {
434+ emitLineTo(cx0 - cmy + cmx, cy0 + cmx + cmy);
435+ emitLineTo(cx0 - cmy - cmx, cy0 + cmx - cmy);
436+ }
437+
438+ emitReverse();
439+
440+ if (capStyle == CAP_ROUND) {
441+ drawRoundCap(sx0, sy0, -smx, -smy);
442+ } else if (capStyle == CAP_SQUARE) {
443+ emitLineTo(sx0 + smy - smx, sy0 - smx - smy);
444+ emitLineTo(sx0 + smy + smx, sy0 - smx + smy);
445+ }
446+
447+ emitClose();
448+ }
449+
450+ private void emitMoveTo(final float x0, final float y0) {
451+ out.moveTo(x0, y0);
452+ }
453+
454+ private void emitLineTo(final float x1, final float y1) {
455+ out.lineTo(x1, y1);
456+ }
457+
458+ private void emitLineTo(final float x1, final float y1,
459+ final boolean rev)
460+ {
461+ if (rev) {
462+ reverse.pushLine(x1, y1);
463+ } else {
464+ emitLineTo(x1, y1);
465+ }
466+ }
467+
468+ private void emitQuadTo(final float x0, final float y0,
469+ final float x1, final float y1,
470+ final float x2, final float y2, final boolean rev)
471+ {
472+ if (rev) {
473+ reverse.pushQuad(x0, y0, x1, y1);
474+ } else {
475+ out.quadTo(x1, y1, x2, y2);
476+ }
477+ }
478+
479+ private void emitCurveTo(final float x0, final float y0,
480+ final float x1, final float y1,
481+ final float x2, final float y2,
482+ final float x3, final float y3, final boolean rev)
483+ {
484+ if (rev) {
485+ reverse.pushCubic(x0, y0, x1, y1, x2, y2);
486+ } else {
487+ out.curveTo(x1, y1, x2, y2, x3, y3);
488+ }
489+ }
490+
491+ private void emitClose() {
492+ out.closePath();
493+ }
494+
495+ private void drawJoin(float pdx, float pdy,
496+ float x0, float y0,
497+ float dx, float dy,
498+ float omx, float omy,
499+ float mx, float my)
500+ {
501+ if (prev != DRAWING_OP_TO) {
502+ emitMoveTo(x0 + mx, y0 + my);
503+ this.sdx = dx;
504+ this.sdy = dy;
505+ this.smx = mx;
506+ this.smy = my;
507+ } else {
508+ boolean cw = isCW(pdx, pdy, dx, dy);
509+ if (joinStyle == JOIN_MITER) {
510+ drawMiter(pdx, pdy, x0, y0, dx, dy, omx, omy, mx, my, cw);
511+ } else if (joinStyle == JOIN_ROUND) {
512+ drawRoundJoin(x0, y0,
513+ omx, omy,
514+ mx, my, cw,
515+ ROUND_JOIN_THRESHOLD);
516+ }
517+ emitLineTo(x0, y0, !cw);
518+ }
519+ prev = DRAWING_OP_TO;
520+ }
521+
522+ private static boolean within(final float x1, final float y1,
523+ final float x2, final float y2,
524+ final float ERR)
525+ {
526+ assert ERR > 0 : "";
527+ // compare taxicab distance. ERR will always be small, so using
528+ // true distance won't give much benefit
529+ return (Helpers.within(x1, x2, ERR) && // we want to avoid calling Math.abs
530+ Helpers.within(y1, y2, ERR)); // this is just as good.
531+ }
532+
533+ private void getLineOffsets(float x1, float y1,
534+ float x2, float y2,
535+ float[] left, float[] right) {
536+ computeOffset(x2 - x1, y2 - y1, lineWidth2, offset[0]);
537+ left[0] = x1 + offset[0][0];
538+ left[1] = y1 + offset[0][1];
539+ left[2] = x2 + offset[0][0];
540+ left[3] = y2 + offset[0][1];
541+ right[0] = x1 - offset[0][0];
542+ right[1] = y1 - offset[0][1];
543+ right[2] = x2 - offset[0][0];
544+ right[3] = y2 - offset[0][1];
545+ }
546+
547+ private int computeOffsetCubic(float[] pts, final int off,
548+ float[] leftOff, float[] rightOff)
549+ {
550+ // if p1=p2 or p3=p4 it means that the derivative at the endpoint
551+ // vanishes, which creates problems with computeOffset. Usually
552+ // this happens when this stroker object is trying to winden
553+ // a curve with a cusp. What happens is that curveTo splits
554+ // the input curve at the cusp, and passes it to this function.
555+ // because of inaccuracies in the splitting, we consider points
556+ // equal if they're very close to each other.
557+ final float x1 = pts[off + 0], y1 = pts[off + 1];
558+ final float x2 = pts[off + 2], y2 = pts[off + 3];
559+ final float x3 = pts[off + 4], y3 = pts[off + 5];
560+ final float x4 = pts[off + 6], y4 = pts[off + 7];
561+
562+ float dx4 = x4 - x3;
563+ float dy4 = y4 - y3;
564+ float dx1 = x2 - x1;
565+ float dy1 = y2 - y1;
566+
567+ // if p1 == p2 && p3 == p4: draw line from p1->p4, unless p1 == p4,
568+ // in which case ignore if p1 == p2
569+ final boolean p1eqp2 = within(x1,y1,x2,y2, 6 * ulp(y2));
570+ final boolean p3eqp4 = within(x3,y3,x4,y4, 6 * ulp(y4));
571+ if (p1eqp2 && p3eqp4) {
572+ getLineOffsets(x1, y1, x4, y4, leftOff, rightOff);
573+ return 4;
574+ } else if (p1eqp2) {
575+ dx1 = x3 - x1;
576+ dy1 = y3 - y1;
577+ } else if (p3eqp4) {
578+ dx4 = x4 - x2;
579+ dy4 = y4 - y2;
580+ }
581+
582+ // if p2-p1 and p4-p3 are parallel, that must mean this curve is a line
583+ float dotsq = (dx1 * dx4 + dy1 * dy4);
584+ dotsq = dotsq * dotsq;
585+ float l1sq = dx1 * dx1 + dy1 * dy1, l4sq = dx4 * dx4 + dy4 * dy4;
586+ if (Helpers.within(dotsq, l1sq * l4sq, 4 * ulp(dotsq))) {
587+ getLineOffsets(x1, y1, x4, y4, leftOff, rightOff);
588+ return 4;
589+ }
590+
591+// What we're trying to do in this function is to approximate an ideal
592+// offset curve (call it I) of the input curve B using a bezier curve Bp.
593+// The constraints I use to get the equations are:
594+//
595+// 1. The computed curve Bp should go through I(0) and I(1). These are
596+// x1p, y1p, x4p, y4p, which are p1p and p4p. We still need to find
597+// 4 variables: the x and y components of p2p and p3p (i.e. x2p, y2p, x3p, y3p).
598+//
599+// 2. Bp should have slope equal in absolute value to I at the endpoints. So,
600+// (by the way, the operator || in the comments below means "aligned with".
601+// It is defined on vectors, so when we say I'(0) || Bp'(0) we mean that
602+// vectors I'(0) and Bp'(0) are aligned, which is the same as saying
603+// that the tangent lines of I and Bp at 0 are parallel. Mathematically
604+// this means (I'(t) || Bp'(t)) <==> (I'(t) = c * Bp'(t)) where c is some
605+// nonzero constant.)
606+// I'(0) || Bp'(0) and I'(1) || Bp'(1). Obviously, I'(0) || B'(0) and
607+// I'(1) || B'(1); therefore, Bp'(0) || B'(0) and Bp'(1) || B'(1).
608+// We know that Bp'(0) || (p2p-p1p) and Bp'(1) || (p4p-p3p) and the same
609+// is true for any bezier curve; therefore, we get the equations
610+// (1) p2p = c1 * (p2-p1) + p1p
611+// (2) p3p = c2 * (p4-p3) + p4p
612+// We know p1p, p4p, p2, p1, p3, and p4; therefore, this reduces the number
613+// of unknowns from 4 to 2 (i.e. just c1 and c2).
614+// To eliminate these 2 unknowns we use the following constraint:
615+//
616+// 3. Bp(0.5) == I(0.5). Bp(0.5)=(x,y) and I(0.5)=(xi,yi), and I should note
617+// that I(0.5) is *the only* reason for computing dxm,dym. This gives us
618+// (3) Bp(0.5) = (p1p + 3 * (p2p + p3p) + p4p)/8, which is equivalent to
619+// (4) p2p + p3p = (Bp(0.5)*8 - p1p - p4p) / 3
620+// We can substitute (1) and (2) from above into (4) and we get:
621+// (5) c1*(p2-p1) + c2*(p4-p3) = (Bp(0.5)*8 - p1p - p4p)/3 - p1p - p4p
622+// which is equivalent to
623+// (6) c1*(p2-p1) + c2*(p4-p3) = (4/3) * (Bp(0.5) * 2 - p1p - p4p)
624+//
625+// The right side of this is a 2D vector, and we know I(0.5), which gives us
626+// Bp(0.5), which gives us the value of the right side.
627+// The left side is just a matrix vector multiplication in disguise. It is
628+//
629+// [x2-x1, x4-x3][c1]
630+// [y2-y1, y4-y3][c2]
631+// which, is equal to
632+// [dx1, dx4][c1]
633+// [dy1, dy4][c2]
634+// At this point we are left with a simple linear system and we solve it by
635+// getting the inverse of the matrix above. Then we use [c1,c2] to compute
636+// p2p and p3p.
637+
638+ float x = 0.125f * (x1 + 3 * (x2 + x3) + x4);
639+ float y = 0.125f * (y1 + 3 * (y2 + y3) + y4);
640+ // (dxm,dym) is some tangent of B at t=0.5. This means it's equal to
641+ // c*B'(0.5) for some constant c.
642+ float dxm = x3 + x4 - x1 - x2, dym = y3 + y4 - y1 - y2;
643+
644+ // this computes the offsets at t=0, 0.5, 1, using the property that
645+ // for any bezier curve the vectors p2-p1 and p4-p3 are parallel to
646+ // the (dx/dt, dy/dt) vectors at the endpoints.
647+ computeOffset(dx1, dy1, lineWidth2, offset[0]);
648+ computeOffset(dxm, dym, lineWidth2, offset[1]);
649+ computeOffset(dx4, dy4, lineWidth2, offset[2]);
650+ float x1p = x1 + offset[0][0]; // start
651+ float y1p = y1 + offset[0][1]; // point
652+ float xi = x + offset[1][0]; // interpolation
653+ float yi = y + offset[1][1]; // point
654+ float x4p = x4 + offset[2][0]; // end
655+ float y4p = y4 + offset[2][1]; // point
656+
657+ float invdet43 = 4f / (3f * (dx1 * dy4 - dy1 * dx4));
658+
659+ float two_pi_m_p1_m_p4x = 2*xi - x1p - x4p;
660+ float two_pi_m_p1_m_p4y = 2*yi - y1p - y4p;
661+ float c1 = invdet43 * (dy4 * two_pi_m_p1_m_p4x - dx4 * two_pi_m_p1_m_p4y);
662+ float c2 = invdet43 * (dx1 * two_pi_m_p1_m_p4y - dy1 * two_pi_m_p1_m_p4x);
663+
664+ float x2p, y2p, x3p, y3p;
665+ x2p = x1p + c1*dx1;
666+ y2p = y1p + c1*dy1;
667+ x3p = x4p + c2*dx4;
668+ y3p = y4p + c2*dy4;
669+
670+ leftOff[0] = x1p; leftOff[1] = y1p;
671+ leftOff[2] = x2p; leftOff[3] = y2p;
672+ leftOff[4] = x3p; leftOff[5] = y3p;
673+ leftOff[6] = x4p; leftOff[7] = y4p;
674+
675+ x1p = x1 - offset[0][0]; y1p = y1 - offset[0][1];
676+ xi = xi - 2 * offset[1][0]; yi = yi - 2 * offset[1][1];
677+ x4p = x4 - offset[2][0]; y4p = y4 - offset[2][1];
678+
679+ two_pi_m_p1_m_p4x = 2*xi - x1p - x4p;
680+ two_pi_m_p1_m_p4y = 2*yi - y1p - y4p;
681+ c1 = invdet43 * (dy4 * two_pi_m_p1_m_p4x - dx4 * two_pi_m_p1_m_p4y);
682+ c2 = invdet43 * (dx1 * two_pi_m_p1_m_p4y - dy1 * two_pi_m_p1_m_p4x);
683+
684+ x2p = x1p + c1*dx1;
685+ y2p = y1p + c1*dy1;
686+ x3p = x4p + c2*dx4;
687+ y3p = y4p + c2*dy4;
688+
689+ rightOff[0] = x1p; rightOff[1] = y1p;
690+ rightOff[2] = x2p; rightOff[3] = y2p;
691+ rightOff[4] = x3p; rightOff[5] = y3p;
692+ rightOff[6] = x4p; rightOff[7] = y4p;
693+ return 8;
694+ }
695+
696+ // return the kind of curve in the right and left arrays.
697+ private int computeOffsetQuad(float[] pts, final int off,
698+ float[] leftOff, float[] rightOff)
699+ {
700+ final float x1 = pts[off + 0], y1 = pts[off + 1];
701+ final float x2 = pts[off + 2], y2 = pts[off + 3];
702+ final float x3 = pts[off + 4], y3 = pts[off + 5];
703+
704+ final float dx3 = x3 - x2;
705+ final float dy3 = y3 - y2;
706+ final float dx1 = x2 - x1;
707+ final float dy1 = y2 - y1;
708+
709+ // this computes the offsets at t = 0, 1
710+ computeOffset(dx1, dy1, lineWidth2, offset[0]);
711+ computeOffset(dx3, dy3, lineWidth2, offset[1]);
712+
713+ leftOff[0] = x1 + offset[0][0]; leftOff[1] = y1 + offset[0][1];
714+ leftOff[4] = x3 + offset[1][0]; leftOff[5] = y3 + offset[1][1];
715+ rightOff[0] = x1 - offset[0][0]; rightOff[1] = y1 - offset[0][1];
716+ rightOff[4] = x3 - offset[1][0]; rightOff[5] = y3 - offset[1][1];
717+
718+ float x1p = leftOff[0]; // start
719+ float y1p = leftOff[1]; // point
720+ float x3p = leftOff[4]; // end
721+ float y3p = leftOff[5]; // point
722+
723+ // Corner cases:
724+ // 1. If the two control vectors are parallel, we'll end up with NaN's
725+ // in leftOff (and rightOff in the body of the if below), so we'll
726+ // do getLineOffsets, which is right.
727+ // 2. If the first or second two points are equal, then (dx1,dy1)==(0,0)
728+ // or (dx3,dy3)==(0,0), so (x1p, y1p)==(x1p+dx1, y1p+dy1)
729+ // or (x3p, y3p)==(x3p-dx3, y3p-dy3), which means that
730+ // computeIntersection will put NaN's in leftOff and right off, and
731+ // we will do getLineOffsets, which is right.
732+ computeIntersection(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, leftOff, 2);
733+ float cx = leftOff[2];
734+ float cy = leftOff[3];
735+
736+ if (!(isFinite(cx) && isFinite(cy))) {
737+ // maybe the right path is not degenerate.
738+ x1p = rightOff[0];
739+ y1p = rightOff[1];
740+ x3p = rightOff[4];
741+ y3p = rightOff[5];
742+ computeIntersection(x1p, y1p, x1p+dx1, y1p+dy1, x3p, y3p, x3p-dx3, y3p-dy3, rightOff, 2);
743+ cx = rightOff[2];
744+ cy = rightOff[3];
745+ if (!(isFinite(cx) && isFinite(cy))) {
746+ // both are degenerate. This curve is a line.
747+ getLineOffsets(x1, y1, x3, y3, leftOff, rightOff);
748+ return 4;
749+ }
750+ // {left,right}Off[0,1,4,5] are already set to the correct values.
751+ leftOff[2] = 2*x2 - cx;
752+ leftOff[3] = 2*y2 - cy;
753+ return 6;
754+ }
755+
756+ // rightOff[2,3] = (x2,y2) - ((left_x2, left_y2) - (x2, y2))
757+ // == 2*(x2, y2) - (left_x2, left_y2)
758+ rightOff[2] = 2*x2 - cx;
759+ rightOff[3] = 2*y2 - cy;
760+ return 6;
761+ }
762+
763+ private static boolean isFinite(float x) {
764+ return (Float.NEGATIVE_INFINITY < x && x < Float.POSITIVE_INFINITY);
765+ }
766+
767+ // This is where the curve to be processed is put. We give it
768+ // enough room to store 2 curves: one for the current subdivision, the
769+ // other for the rest of the curve.
770+ private float[] middle = new float[2*8];
771+ private float[] lp = new float[8];
772+ private float[] rp = new float[8];
773+ private static final int MAX_N_CURVES = 11;
774+ private float[] subdivTs = new float[MAX_N_CURVES - 1];
775+
776+ // If this class is compiled with ecj, then Hotspot crashes when OSR
777+ // compiling this function. See bugs 7004570 and 6675699
778+ // TODO: until those are fixed, we should work around that by
779+ // manually inlining this into curveTo and quadTo.
780+/******************************* WORKAROUND **********************************
781+ private void somethingTo(final int type) {
782+ // need these so we can update the state at the end of this method
783+ final float xf = middle[type-2], yf = middle[type-1];
784+ float dxs = middle[2] - middle[0];
785+ float dys = middle[3] - middle[1];
786+ float dxf = middle[type - 2] - middle[type - 4];
787+ float dyf = middle[type - 1] - middle[type - 3];
788+ switch(type) {
789+ case 6:
790+ if ((dxs == 0f && dys == 0f) ||
791+ (dxf == 0f && dyf == 0f)) {
792+ dxs = dxf = middle[4] - middle[0];
793+ dys = dyf = middle[5] - middle[1];
794+ }
795+ break;
796+ case 8:
797+ boolean p1eqp2 = (dxs == 0f && dys == 0f);
798+ boolean p3eqp4 = (dxf == 0f && dyf == 0f);
799+ if (p1eqp2) {
800+ dxs = middle[4] - middle[0];
801+ dys = middle[5] - middle[1];
802+ if (dxs == 0f && dys == 0f) {
803+ dxs = middle[6] - middle[0];
804+ dys = middle[7] - middle[1];
805+ }
806+ }
807+ if (p3eqp4) {
808+ dxf = middle[6] - middle[2];
809+ dyf = middle[7] - middle[3];
810+ if (dxf == 0f && dyf == 0f) {
811+ dxf = middle[6] - middle[0];
812+ dyf = middle[7] - middle[1];
813+ }
814+ }
815+ }
816+ if (dxs == 0f && dys == 0f) {
817+ // this happens iff the "curve" is just a point
818+ lineTo(middle[0], middle[1]);
819+ return;
820+ }
821+ // if these vectors are too small, normalize them, to avoid future
822+ // precision problems.
823+ if (Math.abs(dxs) < 0.1f && Math.abs(dys) < 0.1f) {
824+ float len = (float) sqrt(dxs*dxs + dys*dys);
825+ dxs /= len;
826+ dys /= len;
827+ }
828+ if (Math.abs(dxf) < 0.1f && Math.abs(dyf) < 0.1f) {
829+ float len = (float) sqrt(dxf*dxf + dyf*dyf);
830+ dxf /= len;
831+ dyf /= len;
832+ }
833+
834+ computeOffset(dxs, dys, lineWidth2, offset[0]);
835+ final float mx = offset[0][0];
836+ final float my = offset[0][1];
837+ drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);
838+
839+ int nSplits = findSubdivPoints(middle, subdivTs, type, lineWidth2);
840+
841+ int kind = 0;
842+ Iterator<Integer> it = Curve.breakPtsAtTs(middle, type, subdivTs, nSplits);
843+ while(it.hasNext()) {
844+ int curCurveOff = it.next();
845+
846+ switch (type) {
847+ case 8:
848+ kind = computeOffsetCubic(middle, curCurveOff, lp, rp);
849+ break;
850+ case 6:
851+ kind = computeOffsetQuad(middle, curCurveOff, lp, rp);
852+ break;
853+ }
854+ emitLineTo(lp[0], lp[1]);
855+ switch(kind) {
856+ case 8:
857+ emitCurveTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], lp[6], lp[7], false);
858+ emitCurveTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], rp[6], rp[7], true);
859+ break;
860+ case 6:
861+ emitQuadTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], false);
862+ emitQuadTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], true);
863+ break;
864+ case 4:
865+ emitLineTo(lp[2], lp[3]);
866+ emitLineTo(rp[0], rp[1], true);
867+ break;
868+ }
869+ emitLineTo(rp[kind - 2], rp[kind - 1], true);
870+ }
871+
872+ this.cmx = (lp[kind - 2] - rp[kind - 2]) / 2;
873+ this.cmy = (lp[kind - 1] - rp[kind - 1]) / 2;
874+ this.cdx = dxf;
875+ this.cdy = dyf;
876+ this.cx0 = xf;
877+ this.cy0 = yf;
878+ this.prev = DRAWING_OP_TO;
879+ }
880+****************************** END WORKAROUND *******************************/
881+
882+ // finds values of t where the curve in pts should be subdivided in order
883+ // to get good offset curves a distance of w away from the middle curve.
884+ // Stores the points in ts, and returns how many of them there were.
885+ private static Curve c = new Curve();
886+ private static int findSubdivPoints(float[] pts, float[] ts, final int type, final float w)
887+ {
888+ final float x12 = pts[2] - pts[0];
889+ final float y12 = pts[3] - pts[1];
890+ // if the curve is already parallel to either axis we gain nothing
891+ // from rotating it.
892+ if (y12 != 0f && x12 != 0f) {
893+ // we rotate it so that the first vector in the control polygon is
894+ // parallel to the x-axis. This will ensure that rotated quarter
895+ // circles won't be subdivided.
896+ final float hypot = (float) sqrt(x12 * x12 + y12 * y12);
897+ final float cos = x12 / hypot;
898+ final float sin = y12 / hypot;
899+ final float x1 = cos * pts[0] + sin * pts[1];
900+ final float y1 = cos * pts[1] - sin * pts[0];
901+ final float x2 = cos * pts[2] + sin * pts[3];
902+ final float y2 = cos * pts[3] - sin * pts[2];
903+ final float x3 = cos * pts[4] + sin * pts[5];
904+ final float y3 = cos * pts[5] - sin * pts[4];
905+ switch(type) {
906+ case 8:
907+ final float x4 = cos * pts[6] + sin * pts[7];
908+ final float y4 = cos * pts[7] - sin * pts[6];
909+ c.set(x1, y1, x2, y2, x3, y3, x4, y4);
910+ break;
911+ case 6:
912+ c.set(x1, y1, x2, y2, x3, y3);
913+ break;
914+ }
915+ } else {
916+ c.set(pts, type);
917+ }
918+
919+ int ret = 0;
920+ // we subdivide at values of t such that the remaining rotated
921+ // curves are monotonic in x and y.
922+ ret += c.dxRoots(ts, ret);
923+ ret += c.dyRoots(ts, ret);
924+ // subdivide at inflection points.
925+ if (type == 8) {
926+ // quadratic curves can't have inflection points
927+ ret += c.infPoints(ts, ret);
928+ }
929+
930+ // now we must subdivide at points where one of the offset curves will have
931+ // a cusp. This happens at ts where the radius of curvature is equal to w.
932+ ret += c.rootsOfROCMinusW(ts, ret, w, 0.0001f);
933+
934+ ret = Helpers.filterOutNotInAB(ts, 0, ret, 0.0001f, 0.9999f);
935+ Helpers.isort(ts, 0, ret);
936+ return ret;
937+ }
938+
939+ @Override public void curveTo(float x1, float y1,
940+ float x2, float y2,
941+ float x3, float y3)
942+ {
943+ middle[0] = cx0; middle[1] = cy0;
944+ middle[2] = x1; middle[3] = y1;
945+ middle[4] = x2; middle[5] = y2;
946+ middle[6] = x3; middle[7] = y3;
947+
948+ // inlined version of somethingTo(8);
949+ // See the TODO on somethingTo
950+
951+ // need these so we can update the state at the end of this method
952+ final float xf = middle[6], yf = middle[7];
953+ float dxs = middle[2] - middle[0];
954+ float dys = middle[3] - middle[1];
955+ float dxf = middle[6] - middle[4];
956+ float dyf = middle[7] - middle[5];
957+
958+ boolean p1eqp2 = (dxs == 0f && dys == 0f);
959+ boolean p3eqp4 = (dxf == 0f && dyf == 0f);
960+ if (p1eqp2) {
961+ dxs = middle[4] - middle[0];
962+ dys = middle[5] - middle[1];
963+ if (dxs == 0f && dys == 0f) {
964+ dxs = middle[6] - middle[0];
965+ dys = middle[7] - middle[1];
966+ }
967+ }
968+ if (p3eqp4) {
969+ dxf = middle[6] - middle[2];
970+ dyf = middle[7] - middle[3];
971+ if (dxf == 0f && dyf == 0f) {
972+ dxf = middle[6] - middle[0];
973+ dyf = middle[7] - middle[1];
974+ }
975+ }
976+ if (dxs == 0f && dys == 0f) {
977+ // this happens iff the "curve" is just a point
978+ lineTo(middle[0], middle[1]);
979+ return;
980+ }
981+
982+ // if these vectors are too small, normalize them, to avoid future
983+ // precision problems.
984+ if (Math.abs(dxs) < 0.1f && Math.abs(dys) < 0.1f) {
985+ float len = (float) sqrt(dxs*dxs + dys*dys);
986+ dxs /= len;
987+ dys /= len;
988+ }
989+ if (Math.abs(dxf) < 0.1f && Math.abs(dyf) < 0.1f) {
990+ float len = (float) sqrt(dxf*dxf + dyf*dyf);
991+ dxf /= len;
992+ dyf /= len;
993+ }
994+
995+ computeOffset(dxs, dys, lineWidth2, offset[0]);
996+ final float mx = offset[0][0];
997+ final float my = offset[0][1];
998+ drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);
999+
1000+ int nSplits = findSubdivPoints(middle, subdivTs, 8, lineWidth2);
1001+
1002+ int kind = 0;
1003+ Iterator<Integer> it = Curve.breakPtsAtTs(middle, 8, subdivTs, nSplits);
1004+ while(it.hasNext()) {
1005+ int curCurveOff = it.next();
1006+
1007+ kind = computeOffsetCubic(middle, curCurveOff, lp, rp);
1008+ emitLineTo(lp[0], lp[1]);
1009+ switch(kind) {
1010+ case 8:
1011+ emitCurveTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], lp[6], lp[7], false);
1012+ emitCurveTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], rp[6], rp[7], true);
1013+ break;
1014+ case 4:
1015+ emitLineTo(lp[2], lp[3]);
1016+ emitLineTo(rp[0], rp[1], true);
1017+ break;
1018+ }
1019+ emitLineTo(rp[kind - 2], rp[kind - 1], true);
1020+ }
1021+
1022+ this.cmx = (lp[kind - 2] - rp[kind - 2]) / 2;
1023+ this.cmy = (lp[kind - 1] - rp[kind - 1]) / 2;
1024+ this.cdx = dxf;
1025+ this.cdy = dyf;
1026+ this.cx0 = xf;
1027+ this.cy0 = yf;
1028+ this.prev = DRAWING_OP_TO;
1029+ }
1030+
1031+ @Override public void quadTo(float x1, float y1, float x2, float y2) {
1032+ middle[0] = cx0; middle[1] = cy0;
1033+ middle[2] = x1; middle[3] = y1;
1034+ middle[4] = x2; middle[5] = y2;
1035+
1036+ // inlined version of somethingTo(8);
1037+ // See the TODO on somethingTo
1038+
1039+ // need these so we can update the state at the end of this method
1040+ final float xf = middle[4], yf = middle[5];
1041+ float dxs = middle[2] - middle[0];
1042+ float dys = middle[3] - middle[1];
1043+ float dxf = middle[4] - middle[2];
1044+ float dyf = middle[5] - middle[3];
1045+ if ((dxs == 0f && dys == 0f) || (dxf == 0f && dyf == 0f)) {
1046+ dxs = dxf = middle[4] - middle[0];
1047+ dys = dyf = middle[5] - middle[1];
1048+ }
1049+ if (dxs == 0f && dys == 0f) {
1050+ // this happens iff the "curve" is just a point
1051+ lineTo(middle[0], middle[1]);
1052+ return;
1053+ }
1054+ // if these vectors are too small, normalize them, to avoid future
1055+ // precision problems.
1056+ if (Math.abs(dxs) < 0.1f && Math.abs(dys) < 0.1f) {
1057+ float len = (float) sqrt(dxs*dxs + dys*dys);
1058+ dxs /= len;
1059+ dys /= len;
1060+ }
1061+ if (Math.abs(dxf) < 0.1f && Math.abs(dyf) < 0.1f) {
1062+ float len = (float) sqrt(dxf*dxf + dyf*dyf);
1063+ dxf /= len;
1064+ dyf /= len;
1065+ }
1066+
1067+ computeOffset(dxs, dys, lineWidth2, offset[0]);
1068+ final float mx = offset[0][0];
1069+ final float my = offset[0][1];
1070+ drawJoin(cdx, cdy, cx0, cy0, dxs, dys, cmx, cmy, mx, my);
1071+
1072+ int nSplits = findSubdivPoints(middle, subdivTs, 6, lineWidth2);
1073+
1074+ int kind = 0;
1075+ Iterator<Integer> it = Curve.breakPtsAtTs(middle, 6, subdivTs, nSplits);
1076+ while(it.hasNext()) {
1077+ int curCurveOff = it.next();
1078+
1079+ kind = computeOffsetQuad(middle, curCurveOff, lp, rp);
1080+ emitLineTo(lp[0], lp[1]);
1081+ switch(kind) {
1082+ case 6:
1083+ emitQuadTo(lp[0], lp[1], lp[2], lp[3], lp[4], lp[5], false);
1084+ emitQuadTo(rp[0], rp[1], rp[2], rp[3], rp[4], rp[5], true);
1085+ break;
1086+ case 4:
1087+ emitLineTo(lp[2], lp[3]);
1088+ emitLineTo(rp[0], rp[1], true);
1089+ break;
1090+ }
1091+ emitLineTo(rp[kind - 2], rp[kind - 1], true);
1092+ }
1093+
1094+ this.cmx = (lp[kind - 2] - rp[kind - 2]) / 2;
1095+ this.cmy = (lp[kind - 1] - rp[kind - 1]) / 2;
1096+ this.cdx = dxf;
1097+ this.cdy = dyf;
1098+ this.cx0 = xf;
1099+ this.cy0 = yf;
1100+ this.prev = DRAWING_OP_TO;
1101+ }
1102+
1103+ @Override public long getNativeConsumer() {
1104+ throw new InternalError("Stroker doesn't use a native consumer");
1105+ }
1106+
1107+ // a stack of polynomial curves where each curve shares endpoints with
1108+ // adjacent ones.
1109+ private static final class PolyStack {
1110+ float[] curves;
1111+ int end;
1112+ int[] curveTypes;
1113+ int numCurves;
1114+
1115+ private static final int INIT_SIZE = 50;
1116+
1117+ PolyStack() {
1118+ curves = new float[8 * INIT_SIZE];
1119+ curveTypes = new int[INIT_SIZE];
1120+ end = 0;
1121+ numCurves = 0;
1122+ }
1123+
1124+ public boolean isEmpty() {
1125+ return numCurves == 0;
1126+ }
1127+
1128+ private void ensureSpace(int n) {
1129+ if (end + n >= curves.length) {
1130+ int newSize = (end + n) * 2;
1131+ curves = Arrays.copyOf(curves, newSize);
1132+ }
1133+ if (numCurves >= curveTypes.length) {
1134+ int newSize = numCurves * 2;
1135+ curveTypes = Arrays.copyOf(curveTypes, newSize);
1136+ }
1137+ }
1138+
1139+ public void pushCubic(float x0, float y0,
1140+ float x1, float y1,
1141+ float x2, float y2)
1142+ {
1143+ ensureSpace(6);
1144+ curveTypes[numCurves++] = 8;
1145+ // assert(x0 == lastX && y0 == lastY)
1146+
1147+ // we reverse the coordinate order to make popping easier
1148+ curves[end++] = x2; curves[end++] = y2;
1149+ curves[end++] = x1; curves[end++] = y1;
1150+ curves[end++] = x0; curves[end++] = y0;
1151+ }
1152+
1153+ public void pushQuad(float x0, float y0,
1154+ float x1, float y1)
1155+ {
1156+ ensureSpace(4);
1157+ curveTypes[numCurves++] = 6;
1158+ // assert(x0 == lastX && y0 == lastY)
1159+ curves[end++] = x1; curves[end++] = y1;
1160+ curves[end++] = x0; curves[end++] = y0;
1161+ }
1162+
1163+ public void pushLine(float x, float y) {
1164+ ensureSpace(2);
1165+ curveTypes[numCurves++] = 4;
1166+ // assert(x0 == lastX && y0 == lastY)
1167+ curves[end++] = x; curves[end++] = y;
1168+ }
1169+
1170+ @SuppressWarnings("unused")
1171+ public int pop(float[] pts) {
1172+ int ret = curveTypes[numCurves - 1];
1173+ numCurves--;
1174+ end -= (ret - 2);
1175+ System.arraycopy(curves, end, pts, 0, ret - 2);
1176+ return ret;
1177+ }
1178+
1179+ public void pop(PathConsumer2D io) {
1180+ numCurves--;
1181+ int type = curveTypes[numCurves];
1182+ end -= (type - 2);
1183+ switch(type) {
1184+ case 8:
1185+ io.curveTo(curves[end+0], curves[end+1],
1186+ curves[end+2], curves[end+3],
1187+ curves[end+4], curves[end+5]);
1188+ break;
1189+ case 6:
1190+ io.quadTo(curves[end+0], curves[end+1],
1191+ curves[end+2], curves[end+3]);
1192+ break;
1193+ case 4:
1194+ io.lineTo(curves[end], curves[end+1]);
1195+ }
1196+ }
1197+
1198+ @Override
1199+ public String toString() {
1200+ String ret = "";
1201+ int nc = numCurves;
1202+ int end = this.end;
1203+ while (nc > 0) {
1204+ nc--;
1205+ int type = curveTypes[numCurves];
1206+ end -= (type - 2);
1207+ switch(type) {
1208+ case 8:
1209+ ret += "cubic: ";
1210+ break;
1211+ case 6:
1212+ ret += "quad: ";
1213+ break;
1214+ case 4:
1215+ ret += "line: ";
1216+ break;
1217+ }
1218+ ret += Arrays.toString(Arrays.copyOfRange(curves, end, end+type-2)) + "\n";
1219+ }
1220+ return ret;
1221+ }
1222+ }
1223+}