1 /*
2 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
4 * Copyright (C) 2007 Alp Toker <alp@atoker.com>
5 * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
6 * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
21 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
24 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
25 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "config.h"
31 #include "CanvasRenderingContext2D.h"
32
33 #include "AffineTransform.h"
34 #include "CSSParser.h"
35 #include "CachedImage.h"
36 #include "CanvasGradient.h"
37 #include "CanvasPattern.h"
38 #include "CanvasStyle.h"
39 #include "CSSMutableStyleDeclaration.h"
40 #include "CSSPropertyNames.h"
41 #include "CSSStyleSelector.h"
42 #include "Document.h"
43 #include "ExceptionCode.h"
44 #include "FloatConversion.h"
45 #include "GraphicsContext.h"
46 #include "HTMLCanvasElement.h"
47 #include "HTMLImageElement.h"
48 #include "HTMLNames.h"
49 #include "ImageBuffer.h"
50 #include "ImageData.h"
51 #include "KURL.h"
52 #include "Page.h"
53 #include "RenderHTMLCanvas.h"
54 #include "SecurityOrigin.h"
55 #include "Settings.h"
56 #include "StrokeStyleApplier.h"
57 #include "TextMetrics.h"
58 #include "HTMLVideoElement.h"
59 #include <stdio.h>
60 #include <wtf/ByteArray.h>
61 #include <wtf/MathExtras.h>
62 #include <wtf/OwnPtr.h>
63 #include <wtf/UnusedParam.h>
64
65 using namespace std;
66
67 namespace WebCore {
68
69 using namespace HTMLNames;
70
71 static const char* const defaultFont = "10px sans-serif";
72
73
74 class CanvasStrokeStyleApplier : public StrokeStyleApplier {
75 public:
CanvasStrokeStyleApplier(CanvasRenderingContext2D * canvasContext)76 CanvasStrokeStyleApplier(CanvasRenderingContext2D* canvasContext)
77 : m_canvasContext(canvasContext)
78 {
79 }
80
strokeStyle(GraphicsContext * c)81 virtual void strokeStyle(GraphicsContext* c)
82 {
83 c->setStrokeThickness(m_canvasContext->lineWidth());
84 c->setLineCap(m_canvasContext->getLineCap());
85 c->setLineJoin(m_canvasContext->getLineJoin());
86 c->setMiterLimit(m_canvasContext->miterLimit());
87 }
88
89 private:
90 CanvasRenderingContext2D* m_canvasContext;
91 };
92
93
94
CanvasRenderingContext2D(HTMLCanvasElement * canvas)95 CanvasRenderingContext2D::CanvasRenderingContext2D(HTMLCanvasElement* canvas)
96 : CanvasRenderingContext(canvas)
97 , m_stateStack(1)
98 {
99 // Make sure that even if the drawingContext() has a different default
100 // thickness, it is in sync with the canvas thickness.
101 setLineWidth(lineWidth());
102 }
103
~CanvasRenderingContext2D()104 CanvasRenderingContext2D::~CanvasRenderingContext2D()
105 {
106 }
107
reset()108 void CanvasRenderingContext2D::reset()
109 {
110 m_stateStack.resize(1);
111 m_stateStack.first() = State();
112 }
113
State()114 CanvasRenderingContext2D::State::State()
115 : m_strokeStyle(CanvasStyle::create("black"))
116 , m_fillStyle(CanvasStyle::create("black"))
117 , m_lineWidth(1)
118 , m_lineCap(ButtCap)
119 , m_lineJoin(MiterJoin)
120 , m_miterLimit(10)
121 , m_shadowBlur(0)
122 , m_shadowColor("black")
123 , m_globalAlpha(1)
124 , m_globalComposite(CompositeSourceOver)
125 , m_invertibleCTM(true)
126 , m_textAlign(StartTextAlign)
127 , m_textBaseline(AlphabeticTextBaseline)
128 , m_unparsedFont(defaultFont)
129 , m_realizedFont(false)
130 {
131 }
132
save()133 void CanvasRenderingContext2D::save()
134 {
135 ASSERT(m_stateStack.size() >= 1);
136 m_stateStack.append(state());
137 GraphicsContext* c = drawingContext();
138 if (!c)
139 return;
140 c->save();
141 }
142
restore()143 void CanvasRenderingContext2D::restore()
144 {
145 ASSERT(m_stateStack.size() >= 1);
146 if (m_stateStack.size() <= 1)
147 return;
148 m_path.transform(state().m_transform);
149 m_stateStack.removeLast();
150 m_path.transform(state().m_transform.inverse());
151 GraphicsContext* c = drawingContext();
152 if (!c)
153 return;
154 c->restore();
155 }
156
strokeStyle() const157 CanvasStyle* CanvasRenderingContext2D::strokeStyle() const
158 {
159 return state().m_strokeStyle.get();
160 }
161
setStrokeStyle(PassRefPtr<CanvasStyle> style)162 void CanvasRenderingContext2D::setStrokeStyle(PassRefPtr<CanvasStyle> style)
163 {
164 if (!style)
165 return;
166
167 if (canvas()->originClean()) {
168 if (CanvasPattern* pattern = style->canvasPattern()) {
169 if (!pattern->originClean())
170 canvas()->setOriginTainted();
171 }
172 }
173
174 state().m_strokeStyle = style;
175 GraphicsContext* c = drawingContext();
176 if (!c)
177 return;
178 state().m_strokeStyle->applyStrokeColor(c);
179 }
180
fillStyle() const181 CanvasStyle* CanvasRenderingContext2D::fillStyle() const
182 {
183 return state().m_fillStyle.get();
184 }
185
setFillStyle(PassRefPtr<CanvasStyle> style)186 void CanvasRenderingContext2D::setFillStyle(PassRefPtr<CanvasStyle> style)
187 {
188 if (!style)
189 return;
190
191 if (canvas()->originClean()) {
192 if (CanvasPattern* pattern = style->canvasPattern()) {
193 if (!pattern->originClean())
194 canvas()->setOriginTainted();
195 }
196 }
197
198 state().m_fillStyle = style;
199 GraphicsContext* c = drawingContext();
200 if (!c)
201 return;
202 state().m_fillStyle->applyFillColor(c);
203 }
204
lineWidth() const205 float CanvasRenderingContext2D::lineWidth() const
206 {
207 return state().m_lineWidth;
208 }
209
setLineWidth(float width)210 void CanvasRenderingContext2D::setLineWidth(float width)
211 {
212 if (!(width > 0))
213 return;
214 state().m_lineWidth = width;
215 GraphicsContext* c = drawingContext();
216 if (!c)
217 return;
218 c->setStrokeThickness(width);
219 }
220
lineCap() const221 String CanvasRenderingContext2D::lineCap() const
222 {
223 return lineCapName(state().m_lineCap);
224 }
225
setLineCap(const String & s)226 void CanvasRenderingContext2D::setLineCap(const String& s)
227 {
228 LineCap cap;
229 if (!parseLineCap(s, cap))
230 return;
231 state().m_lineCap = cap;
232 GraphicsContext* c = drawingContext();
233 if (!c)
234 return;
235 c->setLineCap(cap);
236 }
237
lineJoin() const238 String CanvasRenderingContext2D::lineJoin() const
239 {
240 return lineJoinName(state().m_lineJoin);
241 }
242
setLineJoin(const String & s)243 void CanvasRenderingContext2D::setLineJoin(const String& s)
244 {
245 LineJoin join;
246 if (!parseLineJoin(s, join))
247 return;
248 state().m_lineJoin = join;
249 GraphicsContext* c = drawingContext();
250 if (!c)
251 return;
252 c->setLineJoin(join);
253 }
254
miterLimit() const255 float CanvasRenderingContext2D::miterLimit() const
256 {
257 return state().m_miterLimit;
258 }
259
setMiterLimit(float limit)260 void CanvasRenderingContext2D::setMiterLimit(float limit)
261 {
262 if (!(limit > 0))
263 return;
264 state().m_miterLimit = limit;
265 GraphicsContext* c = drawingContext();
266 if (!c)
267 return;
268 c->setMiterLimit(limit);
269 }
270
shadowOffsetX() const271 float CanvasRenderingContext2D::shadowOffsetX() const
272 {
273 return state().m_shadowOffset.width();
274 }
275
setShadowOffsetX(float x)276 void CanvasRenderingContext2D::setShadowOffsetX(float x)
277 {
278 state().m_shadowOffset.setWidth(x);
279 applyShadow();
280 }
281
shadowOffsetY() const282 float CanvasRenderingContext2D::shadowOffsetY() const
283 {
284 return state().m_shadowOffset.height();
285 }
286
setShadowOffsetY(float y)287 void CanvasRenderingContext2D::setShadowOffsetY(float y)
288 {
289 state().m_shadowOffset.setHeight(y);
290 applyShadow();
291 }
292
shadowBlur() const293 float CanvasRenderingContext2D::shadowBlur() const
294 {
295 return state().m_shadowBlur;
296 }
297
setShadowBlur(float blur)298 void CanvasRenderingContext2D::setShadowBlur(float blur)
299 {
300 state().m_shadowBlur = blur;
301 applyShadow();
302 }
303
shadowColor() const304 String CanvasRenderingContext2D::shadowColor() const
305 {
306 // FIXME: What should this return if you called setShadow with a non-string color?
307 return state().m_shadowColor;
308 }
309
setShadowColor(const String & color)310 void CanvasRenderingContext2D::setShadowColor(const String& color)
311 {
312 state().m_shadowColor = color;
313 applyShadow();
314 }
315
globalAlpha() const316 float CanvasRenderingContext2D::globalAlpha() const
317 {
318 return state().m_globalAlpha;
319 }
320
setGlobalAlpha(float alpha)321 void CanvasRenderingContext2D::setGlobalAlpha(float alpha)
322 {
323 if (!(alpha >= 0 && alpha <= 1))
324 return;
325 state().m_globalAlpha = alpha;
326 GraphicsContext* c = drawingContext();
327 if (!c)
328 return;
329 c->setAlpha(alpha);
330 }
331
globalCompositeOperation() const332 String CanvasRenderingContext2D::globalCompositeOperation() const
333 {
334 return compositeOperatorName(state().m_globalComposite);
335 }
336
setGlobalCompositeOperation(const String & operation)337 void CanvasRenderingContext2D::setGlobalCompositeOperation(const String& operation)
338 {
339 CompositeOperator op;
340 if (!parseCompositeOperator(operation, op))
341 return;
342 state().m_globalComposite = op;
343 GraphicsContext* c = drawingContext();
344 if (!c)
345 return;
346 c->setCompositeOperation(op);
347 }
348
scale(float sx,float sy)349 void CanvasRenderingContext2D::scale(float sx, float sy)
350 {
351 GraphicsContext* c = drawingContext();
352 if (!c)
353 return;
354 if (!state().m_invertibleCTM)
355 return;
356
357 if (!isfinite(sx) | !isfinite(sy))
358 return;
359
360 AffineTransform newTransform = state().m_transform;
361 newTransform.scaleNonUniform(sx, sy);
362 if (!newTransform.isInvertible()) {
363 state().m_invertibleCTM = false;
364 return;
365 }
366
367 state().m_transform = newTransform;
368 c->scale(FloatSize(sx, sy));
369 m_path.transform(AffineTransform().scaleNonUniform(1.0 / sx, 1.0 / sy));
370 }
371
rotate(float angleInRadians)372 void CanvasRenderingContext2D::rotate(float angleInRadians)
373 {
374 GraphicsContext* c = drawingContext();
375 if (!c)
376 return;
377 if (!state().m_invertibleCTM)
378 return;
379
380 if (!isfinite(angleInRadians))
381 return;
382
383 AffineTransform newTransform = state().m_transform;
384 newTransform.rotate(angleInRadians / piDouble * 180.0);
385 if (!newTransform.isInvertible()) {
386 state().m_invertibleCTM = false;
387 return;
388 }
389
390 state().m_transform = newTransform;
391 c->rotate(angleInRadians);
392 m_path.transform(AffineTransform().rotate(-angleInRadians / piDouble * 180.0));
393 }
394
translate(float tx,float ty)395 void CanvasRenderingContext2D::translate(float tx, float ty)
396 {
397 GraphicsContext* c = drawingContext();
398 if (!c)
399 return;
400 if (!state().m_invertibleCTM)
401 return;
402
403 if (!isfinite(tx) | !isfinite(ty))
404 return;
405
406 AffineTransform newTransform = state().m_transform;
407 newTransform.translate(tx, ty);
408 if (!newTransform.isInvertible()) {
409 state().m_invertibleCTM = false;
410 return;
411 }
412
413 state().m_transform = newTransform;
414 c->translate(tx, ty);
415 m_path.transform(AffineTransform().translate(-tx, -ty));
416 }
417
transform(float m11,float m12,float m21,float m22,float dx,float dy)418 void CanvasRenderingContext2D::transform(float m11, float m12, float m21, float m22, float dx, float dy)
419 {
420 GraphicsContext* c = drawingContext();
421 if (!c)
422 return;
423 if (!state().m_invertibleCTM)
424 return;
425
426 if (!isfinite(m11) | !isfinite(m21) | !isfinite(dx) |
427 !isfinite(m12) | !isfinite(m22) | !isfinite(dy))
428 return;
429
430 AffineTransform transform(m11, m12, m21, m22, dx, dy);
431 AffineTransform newTransform = transform * state().m_transform;
432 if (!newTransform.isInvertible()) {
433 state().m_invertibleCTM = false;
434 return;
435 }
436
437 state().m_transform = newTransform;
438 c->concatCTM(transform);
439 m_path.transform(transform.inverse());
440 }
441
setTransform(float m11,float m12,float m21,float m22,float dx,float dy)442 void CanvasRenderingContext2D::setTransform(float m11, float m12, float m21, float m22, float dx, float dy)
443 {
444 GraphicsContext* c = drawingContext();
445 if (!c)
446 return;
447
448 if (!isfinite(m11) | !isfinite(m21) | !isfinite(dx) |
449 !isfinite(m12) | !isfinite(m22) | !isfinite(dy))
450 return;
451
452 AffineTransform ctm = state().m_transform;
453 if (!ctm.isInvertible())
454 return;
455 c->concatCTM(c->getCTM().inverse());
456 c->concatCTM(canvas()->baseTransform());
457 state().m_transform.multiply(ctm.inverse());
458 m_path.transform(ctm);
459
460 state().m_invertibleCTM = true;
461 transform(m11, m12, m21, m22, dx, dy);
462 }
463
setStrokeColor(const String & color)464 void CanvasRenderingContext2D::setStrokeColor(const String& color)
465 {
466 setStrokeStyle(CanvasStyle::create(color));
467 }
468
setStrokeColor(float grayLevel)469 void CanvasRenderingContext2D::setStrokeColor(float grayLevel)
470 {
471 setStrokeStyle(CanvasStyle::create(grayLevel, 1));
472 }
473
setStrokeColor(const String & color,float alpha)474 void CanvasRenderingContext2D::setStrokeColor(const String& color, float alpha)
475 {
476 setStrokeStyle(CanvasStyle::create(color, alpha));
477 }
478
setStrokeColor(float grayLevel,float alpha)479 void CanvasRenderingContext2D::setStrokeColor(float grayLevel, float alpha)
480 {
481 setStrokeStyle(CanvasStyle::create(grayLevel, alpha));
482 }
483
setStrokeColor(float r,float g,float b,float a)484 void CanvasRenderingContext2D::setStrokeColor(float r, float g, float b, float a)
485 {
486 setStrokeStyle(CanvasStyle::create(r, g, b, a));
487 }
488
setStrokeColor(float c,float m,float y,float k,float a)489 void CanvasRenderingContext2D::setStrokeColor(float c, float m, float y, float k, float a)
490 {
491 setStrokeStyle(CanvasStyle::create(c, m, y, k, a));
492 }
493
setFillColor(const String & color)494 void CanvasRenderingContext2D::setFillColor(const String& color)
495 {
496 setFillStyle(CanvasStyle::create(color));
497 }
498
setFillColor(float grayLevel)499 void CanvasRenderingContext2D::setFillColor(float grayLevel)
500 {
501 setFillStyle(CanvasStyle::create(grayLevel, 1));
502 }
503
setFillColor(const String & color,float alpha)504 void CanvasRenderingContext2D::setFillColor(const String& color, float alpha)
505 {
506 setFillStyle(CanvasStyle::create(color, alpha));
507 }
508
setFillColor(float grayLevel,float alpha)509 void CanvasRenderingContext2D::setFillColor(float grayLevel, float alpha)
510 {
511 setFillStyle(CanvasStyle::create(grayLevel, alpha));
512 }
513
setFillColor(float r,float g,float b,float a)514 void CanvasRenderingContext2D::setFillColor(float r, float g, float b, float a)
515 {
516 setFillStyle(CanvasStyle::create(r, g, b, a));
517 }
518
setFillColor(float c,float m,float y,float k,float a)519 void CanvasRenderingContext2D::setFillColor(float c, float m, float y, float k, float a)
520 {
521 setFillStyle(CanvasStyle::create(c, m, y, k, a));
522 }
523
beginPath()524 void CanvasRenderingContext2D::beginPath()
525 {
526 m_path.clear();
527 }
528
closePath()529 void CanvasRenderingContext2D::closePath()
530 {
531 m_path.closeSubpath();
532 }
533
moveTo(float x,float y)534 void CanvasRenderingContext2D::moveTo(float x, float y)
535 {
536 if (!isfinite(x) | !isfinite(y))
537 return;
538 if (!state().m_invertibleCTM)
539 return;
540 m_path.moveTo(FloatPoint(x, y));
541 }
542
lineTo(float x,float y)543 void CanvasRenderingContext2D::lineTo(float x, float y)
544 {
545 if (!isfinite(x) | !isfinite(y))
546 return;
547 if (!state().m_invertibleCTM)
548 return;
549 if (!m_path.hasCurrentPoint())
550 m_path.moveTo(FloatPoint(x, y));
551 else
552 m_path.addLineTo(FloatPoint(x, y));
553 }
554
quadraticCurveTo(float cpx,float cpy,float x,float y)555 void CanvasRenderingContext2D::quadraticCurveTo(float cpx, float cpy, float x, float y)
556 {
557 if (!isfinite(cpx) | !isfinite(cpy) | !isfinite(x) | !isfinite(y))
558 return;
559 if (!state().m_invertibleCTM)
560 return;
561 if (!m_path.hasCurrentPoint())
562 m_path.moveTo(FloatPoint(x, y));
563 else
564 m_path.addQuadCurveTo(FloatPoint(cpx, cpy), FloatPoint(x, y));
565 }
566
bezierCurveTo(float cp1x,float cp1y,float cp2x,float cp2y,float x,float y)567 void CanvasRenderingContext2D::bezierCurveTo(float cp1x, float cp1y, float cp2x, float cp2y, float x, float y)
568 {
569 if (!isfinite(cp1x) | !isfinite(cp1y) | !isfinite(cp2x) | !isfinite(cp2y) | !isfinite(x) | !isfinite(y))
570 return;
571 if (!state().m_invertibleCTM)
572 return;
573 if (!m_path.hasCurrentPoint())
574 m_path.moveTo(FloatPoint(x, y));
575 else
576 m_path.addBezierCurveTo(FloatPoint(cp1x, cp1y), FloatPoint(cp2x, cp2y), FloatPoint(x, y));
577 }
578
arcTo(float x0,float y0,float x1,float y1,float r,ExceptionCode & ec)579 void CanvasRenderingContext2D::arcTo(float x0, float y0, float x1, float y1, float r, ExceptionCode& ec)
580 {
581 ec = 0;
582 if (!isfinite(x0) | !isfinite(y0) | !isfinite(x1) | !isfinite(y1) | !isfinite(r))
583 return;
584
585 if (r < 0) {
586 ec = INDEX_SIZE_ERR;
587 return;
588 }
589 if (!state().m_invertibleCTM)
590 return;
591 m_path.addArcTo(FloatPoint(x0, y0), FloatPoint(x1, y1), r);
592 }
593
arc(float x,float y,float r,float sa,float ea,bool anticlockwise,ExceptionCode & ec)594 void CanvasRenderingContext2D::arc(float x, float y, float r, float sa, float ea, bool anticlockwise, ExceptionCode& ec)
595 {
596 ec = 0;
597 if (!isfinite(x) | !isfinite(y) | !isfinite(r) | !isfinite(sa) | !isfinite(ea))
598 return;
599
600 if (r < 0) {
601 ec = INDEX_SIZE_ERR;
602 return;
603 }
604 if (!state().m_invertibleCTM)
605 return;
606 m_path.addArc(FloatPoint(x, y), r, sa, ea, anticlockwise);
607 }
608
validateRectForCanvas(float & x,float & y,float & width,float & height)609 static bool validateRectForCanvas(float& x, float& y, float& width, float& height)
610 {
611 if (!isfinite(x) | !isfinite(y) | !isfinite(width) | !isfinite(height))
612 return false;
613
614 if (width < 0) {
615 width = -width;
616 x -= width;
617 }
618
619 if (height < 0) {
620 height = -height;
621 y -= height;
622 }
623
624 return true;
625 }
626
rect(float x,float y,float width,float height)627 void CanvasRenderingContext2D::rect(float x, float y, float width, float height)
628 {
629 if (!validateRectForCanvas(x, y, width, height))
630 return;
631 if (!state().m_invertibleCTM)
632 return;
633 m_path.addRect(FloatRect(x, y, width, height));
634 }
635
636 #if ENABLE(DASHBOARD_SUPPORT)
clearPathForDashboardBackwardCompatibilityMode()637 void CanvasRenderingContext2D::clearPathForDashboardBackwardCompatibilityMode()
638 {
639 if (Settings* settings = canvas()->document()->settings())
640 if (settings->usesDashboardBackwardCompatibilityMode())
641 m_path.clear();
642 }
643 #endif
644
fill()645 void CanvasRenderingContext2D::fill()
646 {
647 GraphicsContext* c = drawingContext();
648 if (!c)
649 return;
650 if (!state().m_invertibleCTM)
651 return;
652
653 if (!m_path.isEmpty()) {
654 c->beginPath();
655 c->addPath(m_path);
656 willDraw(m_path.boundingRect());
657 c->fillPath();
658 }
659
660 #if ENABLE(DASHBOARD_SUPPORT)
661 clearPathForDashboardBackwardCompatibilityMode();
662 #endif
663 }
664
stroke()665 void CanvasRenderingContext2D::stroke()
666 {
667 GraphicsContext* c = drawingContext();
668 if (!c)
669 return;
670 if (!state().m_invertibleCTM)
671 return;
672
673 if (!m_path.isEmpty()) {
674 c->beginPath();
675 c->addPath(m_path);
676
677 CanvasStrokeStyleApplier strokeApplier(this);
678 FloatRect boundingRect = m_path.strokeBoundingRect(&strokeApplier);
679 willDraw(boundingRect);
680
681 c->strokePath();
682 }
683
684 #if ENABLE(DASHBOARD_SUPPORT)
685 clearPathForDashboardBackwardCompatibilityMode();
686 #endif
687 }
688
clip()689 void CanvasRenderingContext2D::clip()
690 {
691 GraphicsContext* c = drawingContext();
692 if (!c)
693 return;
694 if (!state().m_invertibleCTM)
695 return;
696 c->canvasClip(m_path);
697 #if ENABLE(DASHBOARD_SUPPORT)
698 clearPathForDashboardBackwardCompatibilityMode();
699 #endif
700 }
701
isPointInPath(const float x,const float y)702 bool CanvasRenderingContext2D::isPointInPath(const float x, const float y)
703 {
704 GraphicsContext* c = drawingContext();
705 if (!c)
706 return false;
707 if (!state().m_invertibleCTM)
708 return false;
709
710 FloatPoint point(x, y);
711 AffineTransform ctm = state().m_transform;
712 FloatPoint transformedPoint = ctm.inverse().mapPoint(point);
713 return m_path.contains(transformedPoint);
714 }
715
clearRect(float x,float y,float width,float height)716 void CanvasRenderingContext2D::clearRect(float x, float y, float width, float height)
717 {
718 if (!validateRectForCanvas(x, y, width, height))
719 return;
720 GraphicsContext* c = drawingContext();
721 if (!c)
722 return;
723 if (!state().m_invertibleCTM)
724 return;
725 FloatRect rect(x, y, width, height);
726 willDraw(rect);
727 c->clearRect(rect);
728 }
729
fillRect(float x,float y,float width,float height)730 void CanvasRenderingContext2D::fillRect(float x, float y, float width, float height)
731 {
732 if (!validateRectForCanvas(x, y, width, height))
733 return;
734
735 GraphicsContext* c = drawingContext();
736 if (!c)
737 return;
738 if (!state().m_invertibleCTM)
739 return;
740
741 FloatRect rect(x, y, width, height);
742 willDraw(rect);
743
744 c->save();
745 c->fillRect(rect);
746 c->restore();
747 }
748
strokeRect(float x,float y,float width,float height)749 void CanvasRenderingContext2D::strokeRect(float x, float y, float width, float height)
750 {
751 if (!validateRectForCanvas(x, y, width, height))
752 return;
753 strokeRect(x, y, width, height, state().m_lineWidth);
754 }
755
strokeRect(float x,float y,float width,float height,float lineWidth)756 void CanvasRenderingContext2D::strokeRect(float x, float y, float width, float height, float lineWidth)
757 {
758 if (!validateRectForCanvas(x, y, width, height))
759 return;
760
761 if (!(lineWidth >= 0))
762 return;
763
764 GraphicsContext* c = drawingContext();
765 if (!c)
766 return;
767 if (!state().m_invertibleCTM)
768 return;
769
770 FloatRect rect(x, y, width, height);
771
772 FloatRect boundingRect = rect;
773 boundingRect.inflate(lineWidth / 2);
774 willDraw(boundingRect);
775
776 c->strokeRect(rect, lineWidth);
777 }
778
779 #if PLATFORM(CG)
adjustedShadowSize(CGFloat width,CGFloat height)780 static inline CGSize adjustedShadowSize(CGFloat width, CGFloat height)
781 {
782 // Work around <rdar://problem/5539388> by ensuring that shadow offsets will get truncated
783 // to the desired integer.
784 static const CGFloat extraShadowOffset = narrowPrecisionToCGFloat(1.0 / 128);
785 if (width > 0)
786 width += extraShadowOffset;
787 else if (width < 0)
788 width -= extraShadowOffset;
789
790 if (height > 0)
791 height += extraShadowOffset;
792 else if (height < 0)
793 height -= extraShadowOffset;
794
795 return CGSizeMake(width, height);
796 }
797 #endif
798
setShadow(float width,float height,float blur)799 void CanvasRenderingContext2D::setShadow(float width, float height, float blur)
800 {
801 state().m_shadowOffset = FloatSize(width, height);
802 state().m_shadowBlur = blur;
803 state().m_shadowColor = "";
804 applyShadow();
805 }
806
setShadow(float width,float height,float blur,const String & color)807 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, const String& color)
808 {
809 state().m_shadowOffset = FloatSize(width, height);
810 state().m_shadowBlur = blur;
811 state().m_shadowColor = color;
812 applyShadow();
813 }
814
setShadow(float width,float height,float blur,float grayLevel)815 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float grayLevel)
816 {
817 state().m_shadowOffset = FloatSize(width, height);
818 state().m_shadowBlur = blur;
819 state().m_shadowColor = "";
820
821 GraphicsContext* c = drawingContext();
822 if (!c)
823 return;
824
825 RGBA32 rgba = makeRGBA32FromFloats(grayLevel, grayLevel, grayLevel, 1.0f);
826 c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba), DeviceColorSpace);
827 }
828
setShadow(float width,float height,float blur,const String & color,float alpha)829 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, const String& color, float alpha)
830 {
831 state().m_shadowOffset = FloatSize(width, height);
832 state().m_shadowBlur = blur;
833 state().m_shadowColor = color;
834
835 GraphicsContext* c = drawingContext();
836 if (!c)
837 return;
838
839 RGBA32 rgba = 0; // default is transparent black
840 if (!state().m_shadowColor.isEmpty())
841 CSSParser::parseColor(rgba, state().m_shadowColor);
842 c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(colorWithOverrideAlpha(rgba, alpha)), DeviceColorSpace);
843 }
844
setShadow(float width,float height,float blur,float grayLevel,float alpha)845 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float grayLevel, float alpha)
846 {
847 state().m_shadowOffset = FloatSize(width, height);
848 state().m_shadowBlur = blur;
849 state().m_shadowColor = "";
850
851 GraphicsContext* c = drawingContext();
852 if (!c)
853 return;
854
855 RGBA32 rgba = makeRGBA32FromFloats(grayLevel, grayLevel, grayLevel, alpha);
856 c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba), DeviceColorSpace);
857 }
858
setShadow(float width,float height,float blur,float r,float g,float b,float a)859 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float r, float g, float b, float a)
860 {
861 state().m_shadowOffset = FloatSize(width, height);
862 state().m_shadowBlur = blur;
863 state().m_shadowColor = "";
864
865 GraphicsContext* c = drawingContext();
866 if (!c)
867 return;
868
869 RGBA32 rgba = makeRGBA32FromFloats(r, g, b, a); // default is transparent black
870 if (!state().m_shadowColor.isEmpty())
871 CSSParser::parseColor(rgba, state().m_shadowColor);
872 c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba), DeviceColorSpace);
873 }
874
setShadow(float width,float height,float blur,float c,float m,float y,float k,float a)875 void CanvasRenderingContext2D::setShadow(float width, float height, float blur, float c, float m, float y, float k, float a)
876 {
877 state().m_shadowOffset = FloatSize(width, height);
878 state().m_shadowBlur = blur;
879 state().m_shadowColor = "";
880
881 GraphicsContext* dc = drawingContext();
882 if (!dc)
883 return;
884 #if PLATFORM(CG)
885 const CGFloat components[5] = { c, m, y, k, a };
886 CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceCMYK();
887 CGColorRef shadowColor = CGColorCreate(colorSpace, components);
888 CGColorSpaceRelease(colorSpace);
889 CGContextSetShadowWithColor(dc->platformContext(), adjustedShadowSize(width, -height), blur, shadowColor);
890 CGColorRelease(shadowColor);
891 #else
892 dc->setShadow(IntSize(width, -height), blur, Color(c, m, y, k, a), DeviceColorSpace);
893 #endif
894 }
895
clearShadow()896 void CanvasRenderingContext2D::clearShadow()
897 {
898 state().m_shadowOffset = FloatSize();
899 state().m_shadowBlur = 0;
900 state().m_shadowColor = "";
901 applyShadow();
902 }
903
applyShadow()904 void CanvasRenderingContext2D::applyShadow()
905 {
906 GraphicsContext* c = drawingContext();
907 if (!c)
908 return;
909
910 RGBA32 rgba = 0; // default is transparent black
911 if (!state().m_shadowColor.isEmpty())
912 CSSParser::parseColor(rgba, state().m_shadowColor);
913 float width = state().m_shadowOffset.width();
914 float height = state().m_shadowOffset.height();
915 c->setShadow(IntSize(width, -height), state().m_shadowBlur, Color(rgba), DeviceColorSpace);
916 }
917
size(HTMLImageElement * image)918 static IntSize size(HTMLImageElement* image)
919 {
920 if (CachedImage* cachedImage = image->cachedImage())
921 return cachedImage->imageSize(1.0f); // FIXME: Not sure about this.
922 return IntSize();
923 }
924
925 #if ENABLE(VIDEO)
size(HTMLVideoElement * video)926 static IntSize size(HTMLVideoElement* video)
927 {
928 if (MediaPlayer* player = video->player())
929 return player->naturalSize();
930 return IntSize();
931 }
932 #endif
933
normalizeRect(const FloatRect & rect)934 static inline FloatRect normalizeRect(const FloatRect& rect)
935 {
936 return FloatRect(min(rect.x(), rect.right()),
937 min(rect.y(), rect.bottom()),
938 max(rect.width(), -rect.width()),
939 max(rect.height(), -rect.height()));
940 }
941
checkOrigin(const KURL & url)942 void CanvasRenderingContext2D::checkOrigin(const KURL& url)
943 {
944 if (canvas()->document()->securityOrigin()->taintsCanvas(url))
945 canvas()->setOriginTainted();
946 }
947
checkOrigin(const String & url)948 void CanvasRenderingContext2D::checkOrigin(const String& url)
949 {
950 checkOrigin(KURL(KURL(), url));
951 }
952
drawImage(HTMLImageElement * image,float x,float y)953 void CanvasRenderingContext2D::drawImage(HTMLImageElement* image, float x, float y)
954 {
955 ASSERT(image);
956 IntSize s = size(image);
957 ExceptionCode ec;
958 drawImage(image, x, y, s.width(), s.height(), ec);
959 }
960
drawImage(HTMLImageElement * image,float x,float y,float width,float height,ExceptionCode & ec)961 void CanvasRenderingContext2D::drawImage(HTMLImageElement* image,
962 float x, float y, float width, float height, ExceptionCode& ec)
963 {
964 ASSERT(image);
965 IntSize s = size(image);
966 drawImage(image, FloatRect(0, 0, s.width(), s.height()), FloatRect(x, y, width, height), ec);
967 }
968
drawImage(HTMLImageElement * image,const FloatRect & srcRect,const FloatRect & dstRect,ExceptionCode & ec)969 void CanvasRenderingContext2D::drawImage(HTMLImageElement* image, const FloatRect& srcRect, const FloatRect& dstRect,
970 ExceptionCode& ec)
971 {
972 ASSERT(image);
973
974 ec = 0;
975
976 FloatRect imageRect = FloatRect(FloatPoint(), size(image));
977 if (!imageRect.contains(normalizeRect(srcRect)) || srcRect.width() == 0 || srcRect.height() == 0) {
978 ec = INDEX_SIZE_ERR;
979 return;
980 }
981
982 if (!dstRect.width() || !dstRect.height())
983 return;
984
985 GraphicsContext* c = drawingContext();
986 if (!c)
987 return;
988 if (!state().m_invertibleCTM)
989 return;
990
991 CachedImage* cachedImage = image->cachedImage();
992 if (!cachedImage)
993 return;
994
995 if (canvas()->originClean())
996 checkOrigin(cachedImage->response().url());
997
998 if (canvas()->originClean() && !cachedImage->image()->hasSingleSecurityOrigin())
999 canvas()->setOriginTainted();
1000
1001 FloatRect sourceRect = c->roundToDevicePixels(srcRect);
1002 FloatRect destRect = c->roundToDevicePixels(dstRect);
1003 willDraw(destRect);
1004 c->drawImage(cachedImage->image(), DeviceColorSpace, destRect, sourceRect, state().m_globalComposite);
1005 }
1006
drawImage(HTMLCanvasElement * canvas,float x,float y)1007 void CanvasRenderingContext2D::drawImage(HTMLCanvasElement* canvas, float x, float y)
1008 {
1009 ASSERT(canvas);
1010 ExceptionCode ec;
1011 drawImage(canvas, x, y, canvas->width(), canvas->height(), ec);
1012 }
1013
drawImage(HTMLCanvasElement * canvas,float x,float y,float width,float height,ExceptionCode & ec)1014 void CanvasRenderingContext2D::drawImage(HTMLCanvasElement* canvas,
1015 float x, float y, float width, float height, ExceptionCode& ec)
1016 {
1017 ASSERT(canvas);
1018 drawImage(canvas, FloatRect(0, 0, canvas->width(), canvas->height()), FloatRect(x, y, width, height), ec);
1019 }
1020
drawImage(HTMLCanvasElement * sourceCanvas,const FloatRect & srcRect,const FloatRect & dstRect,ExceptionCode & ec)1021 void CanvasRenderingContext2D::drawImage(HTMLCanvasElement* sourceCanvas, const FloatRect& srcRect,
1022 const FloatRect& dstRect, ExceptionCode& ec)
1023 {
1024 ASSERT(sourceCanvas);
1025
1026 ec = 0;
1027
1028 FloatRect srcCanvasRect = FloatRect(FloatPoint(), sourceCanvas->size());
1029 if (!srcCanvasRect.contains(normalizeRect(srcRect)) || srcRect.width() == 0 || srcRect.height() == 0) {
1030 ec = INDEX_SIZE_ERR;
1031 return;
1032 }
1033
1034 if (!dstRect.width() || !dstRect.height())
1035 return;
1036
1037 GraphicsContext* c = drawingContext();
1038 if (!c)
1039 return;
1040 if (!state().m_invertibleCTM)
1041 return;
1042
1043 FloatRect sourceRect = c->roundToDevicePixels(srcRect);
1044 FloatRect destRect = c->roundToDevicePixels(dstRect);
1045
1046 // FIXME: Do this through platform-independent GraphicsContext API.
1047 ImageBuffer* buffer = sourceCanvas->buffer();
1048 if (!buffer)
1049 return;
1050
1051 if (!sourceCanvas->originClean())
1052 canvas()->setOriginTainted();
1053
1054 c->drawImage(buffer->image(), DeviceColorSpace, destRect, sourceRect, state().m_globalComposite);
1055 willDraw(destRect); // This call comes after drawImage, since the buffer we draw into may be our own, and we need to make sure it is dirty.
1056 // FIXME: Arguably willDraw should become didDraw and occur after drawing calls and not before them to avoid problems like this.
1057 }
1058
1059 #if ENABLE(VIDEO)
drawImage(HTMLVideoElement * video,float x,float y)1060 void CanvasRenderingContext2D::drawImage(HTMLVideoElement* video, float x, float y)
1061 {
1062 ASSERT(video);
1063 IntSize s = size(video);
1064 ExceptionCode ec;
1065 drawImage(video, x, y, s.width(), s.height(), ec);
1066 }
1067
drawImage(HTMLVideoElement * video,float x,float y,float width,float height,ExceptionCode & ec)1068 void CanvasRenderingContext2D::drawImage(HTMLVideoElement* video,
1069 float x, float y, float width, float height, ExceptionCode& ec)
1070 {
1071 ASSERT(video);
1072 IntSize s = size(video);
1073 drawImage(video, FloatRect(0, 0, s.width(), s.height()), FloatRect(x, y, width, height), ec);
1074 }
1075
drawImage(HTMLVideoElement * video,const FloatRect & srcRect,const FloatRect & dstRect,ExceptionCode & ec)1076 void CanvasRenderingContext2D::drawImage(HTMLVideoElement* video, const FloatRect& srcRect, const FloatRect& dstRect,
1077 ExceptionCode& ec)
1078 {
1079 ASSERT(video);
1080
1081 ec = 0;
1082 FloatRect videoRect = FloatRect(FloatPoint(), size(video));
1083 if (!videoRect.contains(normalizeRect(srcRect)) || srcRect.width() == 0 || srcRect.height() == 0) {
1084 ec = INDEX_SIZE_ERR;
1085 return;
1086 }
1087
1088 if (!dstRect.width() || !dstRect.height())
1089 return;
1090
1091 GraphicsContext* c = drawingContext();
1092 if (!c)
1093 return;
1094 if (!state().m_invertibleCTM)
1095 return;
1096
1097 if (canvas()->originClean())
1098 checkOrigin(video->currentSrc());
1099
1100 if (canvas()->originClean() && !video->hasSingleSecurityOrigin())
1101 canvas()->setOriginTainted();
1102
1103 FloatRect sourceRect = c->roundToDevicePixels(srcRect);
1104 FloatRect destRect = c->roundToDevicePixels(dstRect);
1105 willDraw(destRect);
1106
1107 c->save();
1108 c->clip(destRect);
1109 c->translate(destRect.x(), destRect.y());
1110 c->scale(FloatSize(destRect.width()/sourceRect.width(), destRect.height()/sourceRect.height()));
1111 c->translate(-sourceRect.x(), -sourceRect.y());
1112 video->paintCurrentFrameInContext(c, IntRect(IntPoint(), size(video)));
1113 c->restore();
1114 }
1115 #endif
1116
1117 // FIXME: Why isn't this just another overload of drawImage? Why have a different name?
drawImageFromRect(HTMLImageElement * image,float sx,float sy,float sw,float sh,float dx,float dy,float dw,float dh,const String & compositeOperation)1118 void CanvasRenderingContext2D::drawImageFromRect(HTMLImageElement* image,
1119 float sx, float sy, float sw, float sh,
1120 float dx, float dy, float dw, float dh,
1121 const String& compositeOperation)
1122 {
1123 if (!image)
1124 return;
1125
1126 CachedImage* cachedImage = image->cachedImage();
1127 if (!cachedImage)
1128 return;
1129
1130 if (canvas()->originClean())
1131 checkOrigin(cachedImage->response().url());
1132
1133 if (canvas()->originClean() && !cachedImage->image()->hasSingleSecurityOrigin())
1134 canvas()->setOriginTainted();
1135
1136 GraphicsContext* c = drawingContext();
1137 if (!c)
1138 return;
1139 if (!state().m_invertibleCTM)
1140 return;
1141
1142 CompositeOperator op;
1143 if (!parseCompositeOperator(compositeOperation, op))
1144 op = CompositeSourceOver;
1145
1146 FloatRect destRect = FloatRect(dx, dy, dw, dh);
1147 willDraw(destRect);
1148 c->drawImage(cachedImage->image(), DeviceColorSpace, destRect, FloatRect(sx, sy, sw, sh), op);
1149 }
1150
setAlpha(float alpha)1151 void CanvasRenderingContext2D::setAlpha(float alpha)
1152 {
1153 setGlobalAlpha(alpha);
1154 }
1155
setCompositeOperation(const String & operation)1156 void CanvasRenderingContext2D::setCompositeOperation(const String& operation)
1157 {
1158 setGlobalCompositeOperation(operation);
1159 }
1160
prepareGradientForDashboard(CanvasGradient * gradient) const1161 void CanvasRenderingContext2D::prepareGradientForDashboard(CanvasGradient* gradient) const
1162 {
1163 #if ENABLE(DASHBOARD_SUPPORT)
1164 if (Settings* settings = canvas()->document()->settings())
1165 if (settings->usesDashboardBackwardCompatibilityMode())
1166 gradient->setDashboardCompatibilityMode();
1167 #else
1168 UNUSED_PARAM(gradient);
1169 #endif
1170 }
1171
createLinearGradient(float x0,float y0,float x1,float y1,ExceptionCode & ec)1172 PassRefPtr<CanvasGradient> CanvasRenderingContext2D::createLinearGradient(float x0, float y0, float x1, float y1, ExceptionCode& ec)
1173 {
1174 if (!isfinite(x0) || !isfinite(y0) || !isfinite(x1) || !isfinite(y1)) {
1175 ec = NOT_SUPPORTED_ERR;
1176 return 0;
1177 }
1178
1179 PassRefPtr<CanvasGradient> gradient = CanvasGradient::create(FloatPoint(x0, y0), FloatPoint(x1, y1));
1180 prepareGradientForDashboard(gradient.get());
1181 return gradient;
1182 }
1183
createRadialGradient(float x0,float y0,float r0,float x1,float y1,float r1,ExceptionCode & ec)1184 PassRefPtr<CanvasGradient> CanvasRenderingContext2D::createRadialGradient(float x0, float y0, float r0, float x1, float y1, float r1, ExceptionCode& ec)
1185 {
1186 if (!isfinite(x0) || !isfinite(y0) || !isfinite(r0) ||
1187 !isfinite(x1) || !isfinite(y1) || !isfinite(r1)) {
1188 ec = NOT_SUPPORTED_ERR;
1189 return 0;
1190 }
1191 PassRefPtr<CanvasGradient> gradient = CanvasGradient::create(FloatPoint(x0, y0), r0, FloatPoint(x1, y1), r1);
1192 prepareGradientForDashboard(gradient.get());
1193 return gradient;
1194 }
1195
createPattern(HTMLImageElement * image,const String & repetitionType,ExceptionCode & ec)1196 PassRefPtr<CanvasPattern> CanvasRenderingContext2D::createPattern(HTMLImageElement* image,
1197 const String& repetitionType, ExceptionCode& ec)
1198 {
1199 bool repeatX, repeatY;
1200 ec = 0;
1201 CanvasPattern::parseRepetitionType(repetitionType, repeatX, repeatY, ec);
1202 if (ec)
1203 return 0;
1204
1205 if (!image->complete()) {
1206 ec = INVALID_STATE_ERR;
1207 return 0;
1208 }
1209
1210 CachedImage* cachedImage = image->cachedImage();
1211 if (!cachedImage || !image->cachedImage()->image())
1212 return CanvasPattern::create(Image::nullImage(), repeatX, repeatY, true);
1213
1214 bool originClean = !canvas()->document()->securityOrigin()->taintsCanvas(KURL(KURL(), cachedImage->response().url())) && cachedImage->image()->hasSingleSecurityOrigin();
1215 return CanvasPattern::create(cachedImage->image(), repeatX, repeatY, originClean);
1216 }
1217
createPattern(HTMLCanvasElement * canvas,const String & repetitionType,ExceptionCode & ec)1218 PassRefPtr<CanvasPattern> CanvasRenderingContext2D::createPattern(HTMLCanvasElement* canvas,
1219 const String& repetitionType, ExceptionCode& ec)
1220 {
1221 if (!canvas->width() || !canvas->height()) {
1222 ec = INVALID_STATE_ERR;
1223 return 0;
1224 }
1225
1226 bool repeatX, repeatY;
1227 ec = 0;
1228 CanvasPattern::parseRepetitionType(repetitionType, repeatX, repeatY, ec);
1229 if (ec)
1230 return 0;
1231 return CanvasPattern::create(canvas->buffer()->image(), repeatX, repeatY, canvas->originClean());
1232 }
1233
willDraw(const FloatRect & r,unsigned options)1234 void CanvasRenderingContext2D::willDraw(const FloatRect& r, unsigned options)
1235 {
1236 GraphicsContext* c = drawingContext();
1237 if (!c)
1238 return;
1239 if (!state().m_invertibleCTM)
1240 return;
1241
1242 FloatRect dirtyRect = r;
1243 if (options & CanvasWillDrawApplyTransform) {
1244 AffineTransform ctm = state().m_transform;
1245 dirtyRect = ctm.mapRect(r);
1246 }
1247
1248 if (options & CanvasWillDrawApplyShadow) {
1249 // The shadow gets applied after transformation
1250 FloatRect shadowRect(dirtyRect);
1251 shadowRect.move(state().m_shadowOffset);
1252 shadowRect.inflate(state().m_shadowBlur);
1253 dirtyRect.unite(shadowRect);
1254 }
1255
1256 if (options & CanvasWillDrawApplyClip) {
1257 // FIXME: apply the current clip to the rectangle. Unfortunately we can't get the clip
1258 // back out of the GraphicsContext, so to take clip into account for incremental painting,
1259 // we'd have to keep the clip path around.
1260 }
1261
1262 canvas()->willDraw(dirtyRect);
1263 }
1264
drawingContext() const1265 GraphicsContext* CanvasRenderingContext2D::drawingContext() const
1266 {
1267 return canvas()->drawingContext();
1268 }
1269
createEmptyImageData(const IntSize & size)1270 static PassRefPtr<ImageData> createEmptyImageData(const IntSize& size)
1271 {
1272 RefPtr<ImageData> data = ImageData::create(size.width(), size.height());
1273 memset(data->data()->data()->data(), 0, data->data()->data()->length());
1274 return data.get();
1275 }
1276
createImageData(float sw,float sh,ExceptionCode & ec) const1277 PassRefPtr<ImageData> CanvasRenderingContext2D::createImageData(float sw, float sh, ExceptionCode& ec) const
1278 {
1279 ec = 0;
1280 if (!isfinite(sw) || !isfinite(sh)) {
1281 ec = NOT_SUPPORTED_ERR;
1282 return 0;
1283 }
1284 FloatSize unscaledSize(sw, sh);
1285 IntSize scaledSize = canvas()->convertLogicalToDevice(unscaledSize);
1286 if (scaledSize.width() < 1)
1287 scaledSize.setWidth(1);
1288 if (scaledSize.height() < 1)
1289 scaledSize.setHeight(1);
1290
1291 return createEmptyImageData(scaledSize);
1292 }
1293
getImageData(float sx,float sy,float sw,float sh,ExceptionCode & ec) const1294 PassRefPtr<ImageData> CanvasRenderingContext2D::getImageData(float sx, float sy, float sw, float sh, ExceptionCode& ec) const
1295 {
1296 if (!canvas()->originClean()) {
1297 ec = SECURITY_ERR;
1298 return 0;
1299 }
1300
1301 FloatRect unscaledRect(sx, sy, sw, sh);
1302 IntRect scaledRect = canvas()->convertLogicalToDevice(unscaledRect);
1303 if (scaledRect.width() < 1)
1304 scaledRect.setWidth(1);
1305 if (scaledRect.height() < 1)
1306 scaledRect.setHeight(1);
1307 ImageBuffer* buffer = canvas() ? canvas()->buffer() : 0;
1308 if (!buffer)
1309 return createEmptyImageData(scaledRect.size());
1310 return buffer->getUnmultipliedImageData(scaledRect);
1311 }
1312
putImageData(ImageData * data,float dx,float dy,ExceptionCode & ec)1313 void CanvasRenderingContext2D::putImageData(ImageData* data, float dx, float dy, ExceptionCode& ec)
1314 {
1315 if (!data) {
1316 ec = TYPE_MISMATCH_ERR;
1317 return;
1318 }
1319 putImageData(data, dx, dy, 0, 0, data->width(), data->height(), ec);
1320 }
1321
putImageData(ImageData * data,float dx,float dy,float dirtyX,float dirtyY,float dirtyWidth,float dirtyHeight,ExceptionCode & ec)1322 void CanvasRenderingContext2D::putImageData(ImageData* data, float dx, float dy, float dirtyX, float dirtyY,
1323 float dirtyWidth, float dirtyHeight, ExceptionCode& ec)
1324 {
1325 if (!data) {
1326 ec = TYPE_MISMATCH_ERR;
1327 return;
1328 }
1329 if (!isfinite(dx) || !isfinite(dy) || !isfinite(dirtyX) ||
1330 !isfinite(dirtyY) || !isfinite(dirtyWidth) || !isfinite(dirtyHeight)) {
1331 ec = INDEX_SIZE_ERR;
1332 return;
1333 }
1334
1335 ImageBuffer* buffer = canvas()->buffer();
1336 if (!buffer)
1337 return;
1338
1339 if (dirtyWidth < 0) {
1340 dirtyX += dirtyWidth;
1341 dirtyWidth = -dirtyWidth;
1342 }
1343
1344 if (dirtyHeight < 0) {
1345 dirtyY += dirtyHeight;
1346 dirtyHeight = -dirtyHeight;
1347 }
1348
1349 FloatRect clipRect(dirtyX, dirtyY, dirtyWidth, dirtyHeight);
1350 clipRect.intersect(IntRect(0, 0, data->width(), data->height()));
1351 IntSize destOffset(static_cast<int>(dx), static_cast<int>(dy));
1352 IntRect sourceRect = enclosingIntRect(clipRect);
1353 sourceRect.move(destOffset);
1354 sourceRect.intersect(IntRect(IntPoint(), buffer->size()));
1355 if (sourceRect.isEmpty())
1356 return;
1357 willDraw(sourceRect, 0); // ignore transform, shadow and clip
1358 sourceRect.move(-destOffset);
1359 IntPoint destPoint(destOffset.width(), destOffset.height());
1360
1361 buffer->putUnmultipliedImageData(data, sourceRect, destPoint);
1362 }
1363
font() const1364 String CanvasRenderingContext2D::font() const
1365 {
1366 return state().m_unparsedFont;
1367 }
1368
setFont(const String & newFont)1369 void CanvasRenderingContext2D::setFont(const String& newFont)
1370 {
1371 RefPtr<CSSMutableStyleDeclaration> tempDecl = CSSMutableStyleDeclaration::create();
1372 CSSParser parser(!canvas()->document()->inCompatMode()); // Use the parse mode of the canvas' document when parsing CSS.
1373
1374 String declarationText("font: ");
1375 declarationText += newFont;
1376 parser.parseDeclaration(tempDecl.get(), declarationText);
1377 if (!tempDecl->length())
1378 return;
1379
1380 // The parse succeeded.
1381 state().m_unparsedFont = newFont;
1382
1383 // Map the <canvas> font into the text style. If the font uses keywords like larger/smaller, these will work
1384 // relative to the canvas.
1385 RefPtr<RenderStyle> newStyle = RenderStyle::create();
1386 if (canvas()->computedStyle())
1387 newStyle->setFontDescription(canvas()->computedStyle()->fontDescription());
1388
1389 // Now map the font property into the style.
1390 CSSStyleSelector* styleSelector = canvas()->document()->styleSelector();
1391 styleSelector->applyPropertyToStyle(CSSPropertyFont, tempDecl->getPropertyCSSValue(CSSPropertyFont).get(), newStyle.get());
1392
1393 state().m_font = newStyle->font();
1394 state().m_font.update(styleSelector->fontSelector());
1395 state().m_realizedFont = true;
1396 }
1397
textAlign() const1398 String CanvasRenderingContext2D::textAlign() const
1399 {
1400 return textAlignName(state().m_textAlign);
1401 }
1402
setTextAlign(const String & s)1403 void CanvasRenderingContext2D::setTextAlign(const String& s)
1404 {
1405 TextAlign align;
1406 if (!parseTextAlign(s, align))
1407 return;
1408 state().m_textAlign = align;
1409 }
1410
textBaseline() const1411 String CanvasRenderingContext2D::textBaseline() const
1412 {
1413 return textBaselineName(state().m_textBaseline);
1414 }
1415
setTextBaseline(const String & s)1416 void CanvasRenderingContext2D::setTextBaseline(const String& s)
1417 {
1418 TextBaseline baseline;
1419 if (!parseTextBaseline(s, baseline))
1420 return;
1421 state().m_textBaseline = baseline;
1422 }
1423
fillText(const String & text,float x,float y)1424 void CanvasRenderingContext2D::fillText(const String& text, float x, float y)
1425 {
1426 drawTextInternal(text, x, y, true);
1427 }
1428
fillText(const String & text,float x,float y,float maxWidth)1429 void CanvasRenderingContext2D::fillText(const String& text, float x, float y, float maxWidth)
1430 {
1431 drawTextInternal(text, x, y, true, maxWidth, true);
1432 }
1433
strokeText(const String & text,float x,float y)1434 void CanvasRenderingContext2D::strokeText(const String& text, float x, float y)
1435 {
1436 drawTextInternal(text, x, y, false);
1437 }
1438
strokeText(const String & text,float x,float y,float maxWidth)1439 void CanvasRenderingContext2D::strokeText(const String& text, float x, float y, float maxWidth)
1440 {
1441 drawTextInternal(text, x, y, false, maxWidth, true);
1442 }
1443
measureText(const String & text)1444 PassRefPtr<TextMetrics> CanvasRenderingContext2D::measureText(const String& text)
1445 {
1446 RefPtr<TextMetrics> metrics = TextMetrics::create();
1447 metrics->setWidth(accessFont().width(TextRun(text.characters(), text.length())));
1448 return metrics;
1449 }
1450
drawTextInternal(const String & text,float x,float y,bool fill,float,bool)1451 void CanvasRenderingContext2D::drawTextInternal(const String& text, float x, float y, bool fill, float /*maxWidth*/, bool /*useMaxWidth*/)
1452 {
1453 GraphicsContext* c = drawingContext();
1454 if (!c)
1455 return;
1456 if (!state().m_invertibleCTM)
1457 return;
1458
1459 const Font& font = accessFont();
1460
1461 // FIXME: Handle maxWidth.
1462 // FIXME: Need to turn off font smoothing.
1463
1464 bool rtl = canvas()->computedStyle() ? canvas()->computedStyle()->direction() == RTL : false;
1465 bool override = canvas()->computedStyle() ? canvas()->computedStyle()->unicodeBidi() == Override : false;
1466
1467 unsigned length = text.length();
1468 const UChar* string = text.characters();
1469 TextRun textRun(string, length, 0, 0, 0, rtl, override, false, false);
1470
1471 // Draw the item text at the correct point.
1472 FloatPoint location(x, y);
1473 switch (state().m_textBaseline) {
1474 case TopTextBaseline:
1475 case HangingTextBaseline:
1476 location.setY(y + font.ascent());
1477 break;
1478 case BottomTextBaseline:
1479 case IdeographicTextBaseline:
1480 location.setY(y - font.descent());
1481 break;
1482 case MiddleTextBaseline:
1483 location.setY(y - font.descent() + font.height() / 2);
1484 break;
1485 case AlphabeticTextBaseline:
1486 default:
1487 // Do nothing.
1488 break;
1489 }
1490
1491 float width = font.width(TextRun(text, false, 0, 0, rtl, override));
1492
1493 TextAlign align = state().m_textAlign;
1494 if (align == StartTextAlign)
1495 align = rtl ? RightTextAlign : LeftTextAlign;
1496 else if (align == EndTextAlign)
1497 align = rtl ? LeftTextAlign : RightTextAlign;
1498
1499 switch (align) {
1500 case CenterTextAlign:
1501 location.setX(location.x() - width / 2);
1502 break;
1503 case RightTextAlign:
1504 location.setX(location.x() - width);
1505 break;
1506 default:
1507 break;
1508 }
1509
1510 // The slop built in to this mask rect matches the heuristic used in FontCGWin.cpp for GDI text.
1511 FloatRect textRect = FloatRect(location.x() - font.height() / 2, location.y() - font.ascent() - font.lineGap(),
1512 width + font.height(), font.lineSpacing());
1513 if (!fill)
1514 textRect.inflate(c->strokeThickness() / 2);
1515
1516 if (fill)
1517 canvas()->willDraw(textRect);
1518 else {
1519 // When stroking text, pointy miters can extend outside of textRect, so we
1520 // punt and dirty the whole canvas.
1521 canvas()->willDraw(FloatRect(0, 0, canvas()->width(), canvas()->height()));
1522 }
1523
1524 #if PLATFORM(CG)
1525 CanvasStyle* drawStyle = fill ? state().m_fillStyle.get() : state().m_strokeStyle.get();
1526 if (drawStyle->canvasGradient() || drawStyle->canvasPattern()) {
1527 // FIXME: The rect is not big enough for miters on stroked text.
1528 IntRect maskRect = enclosingIntRect(textRect);
1529
1530 OwnPtr<ImageBuffer> maskImage = ImageBuffer::create(maskRect.size());
1531
1532 GraphicsContext* maskImageContext = maskImage->context();
1533
1534 if (fill)
1535 maskImageContext->setFillColor(Color::black, DeviceColorSpace);
1536 else {
1537 maskImageContext->setStrokeColor(Color::black, DeviceColorSpace);
1538 maskImageContext->setStrokeThickness(c->strokeThickness());
1539 }
1540
1541 maskImageContext->setTextDrawingMode(fill ? cTextFill : cTextStroke);
1542 maskImageContext->translate(-maskRect.x(), -maskRect.y());
1543
1544 maskImageContext->drawBidiText(font, textRun, location);
1545
1546 c->save();
1547 c->clipToImageBuffer(maskRect, maskImage.get());
1548 drawStyle->applyFillColor(c);
1549 c->fillRect(maskRect);
1550 c->restore();
1551
1552 return;
1553 }
1554 #endif
1555
1556 c->setTextDrawingMode(fill ? cTextFill : cTextStroke);
1557 c->drawBidiText(font, textRun, location);
1558 }
1559
accessFont()1560 const Font& CanvasRenderingContext2D::accessFont()
1561 {
1562 if (!state().m_realizedFont)
1563 setFont(state().m_unparsedFont);
1564 return state().m_font;
1565 }
1566
1567 } // namespace WebCore
1568