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1 /*
2  * Copyright 2006 The Android Open Source Project
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #define __STDC_LIMIT_MACROS
9 
10 #include "SkArenaAlloc.h"
11 #include "SkAutoBlitterChoose.h"
12 #include "SkBlendModePriv.h"
13 #include "SkBlitter.h"
14 #include "SkCanvas.h"
15 #include "SkColorPriv.h"
16 #include "SkDevice.h"
17 #include "SkDeviceLooper.h"
18 #include "SkDraw.h"
19 #include "SkDrawProcs.h"
20 #include "SkFindAndPlaceGlyph.h"
21 #include "SkMaskFilter.h"
22 #include "SkMatrix.h"
23 #include "SkMatrixUtils.h"
24 #include "SkPaint.h"
25 #include "SkPathEffect.h"
26 #include "SkRasterClip.h"
27 #include "SkRasterizer.h"
28 #include "SkRRect.h"
29 #include "SkScan.h"
30 #include "SkShader.h"
31 #include "SkString.h"
32 #include "SkStroke.h"
33 #include "SkStrokeRec.h"
34 #include "SkTemplates.h"
35 #include "SkTextMapStateProc.h"
36 #include "SkTLazy.h"
37 #include "SkUtils.h"
38 
make_paint_with_image(const SkPaint & origPaint,const SkBitmap & bitmap,SkMatrix * matrix=nullptr)39 static SkPaint make_paint_with_image(
40     const SkPaint& origPaint, const SkBitmap& bitmap, SkMatrix* matrix = nullptr) {
41     SkPaint paint(origPaint);
42     paint.setShader(SkMakeBitmapShader(bitmap, SkShader::kClamp_TileMode,
43                                        SkShader::kClamp_TileMode, matrix,
44                                        kNever_SkCopyPixelsMode));
45     return paint;
46 }
47 
48 ///////////////////////////////////////////////////////////////////////////////
49 
SkDraw()50 SkDraw::SkDraw() {
51     sk_bzero(this, sizeof(*this));
52 }
53 
computeConservativeLocalClipBounds(SkRect * localBounds) const54 bool SkDraw::computeConservativeLocalClipBounds(SkRect* localBounds) const {
55     if (fRC->isEmpty()) {
56         return false;
57     }
58 
59     SkMatrix inverse;
60     if (!fMatrix->invert(&inverse)) {
61         return false;
62     }
63 
64     SkIRect devBounds = fRC->getBounds();
65     // outset to have slop for antialasing and hairlines
66     devBounds.outset(1, 1);
67     inverse.mapRect(localBounds, SkRect::Make(devBounds));
68     return true;
69 }
70 
71 ///////////////////////////////////////////////////////////////////////////////
72 
73 typedef void (*BitmapXferProc)(void* pixels, size_t bytes, uint32_t data);
74 
D_Clear_BitmapXferProc(void * pixels,size_t bytes,uint32_t)75 static void D_Clear_BitmapXferProc(void* pixels, size_t bytes, uint32_t) {
76     sk_bzero(pixels, bytes);
77 }
78 
D_Dst_BitmapXferProc(void *,size_t,uint32_t data)79 static void D_Dst_BitmapXferProc(void*, size_t, uint32_t data) {}
80 
D32_Src_BitmapXferProc(void * pixels,size_t bytes,uint32_t data)81 static void D32_Src_BitmapXferProc(void* pixels, size_t bytes, uint32_t data) {
82     sk_memset32((uint32_t*)pixels, data, SkToInt(bytes >> 2));
83 }
84 
D16_Src_BitmapXferProc(void * pixels,size_t bytes,uint32_t data)85 static void D16_Src_BitmapXferProc(void* pixels, size_t bytes, uint32_t data) {
86     sk_memset16((uint16_t*)pixels, data, SkToInt(bytes >> 1));
87 }
88 
DA8_Src_BitmapXferProc(void * pixels,size_t bytes,uint32_t data)89 static void DA8_Src_BitmapXferProc(void* pixels, size_t bytes, uint32_t data) {
90     memset(pixels, data, bytes);
91 }
92 
ChooseBitmapXferProc(const SkPixmap & dst,const SkPaint & paint,uint32_t * data)93 static BitmapXferProc ChooseBitmapXferProc(const SkPixmap& dst, const SkPaint& paint,
94                                            uint32_t* data) {
95     // todo: we can apply colorfilter up front if no shader, so we wouldn't
96     // need to abort this fastpath
97     if (paint.getShader() || paint.getColorFilter() || dst.colorSpace()) {
98         return nullptr;
99     }
100 
101     SkBlendMode mode = paint.getBlendMode();
102     SkColor color = paint.getColor();
103 
104     // collaps modes based on color...
105     if (SkBlendMode::kSrcOver == mode) {
106         unsigned alpha = SkColorGetA(color);
107         if (0 == alpha) {
108             mode = SkBlendMode::kDst;
109         } else if (0xFF == alpha) {
110             mode = SkBlendMode::kSrc;
111         }
112     }
113 
114     switch (mode) {
115         case SkBlendMode::kClear:
116 //            SkDebugf("--- D_Clear_BitmapXferProc\n");
117             return D_Clear_BitmapXferProc;  // ignore data
118         case SkBlendMode::kDst:
119 //            SkDebugf("--- D_Dst_BitmapXferProc\n");
120             return D_Dst_BitmapXferProc;    // ignore data
121         case SkBlendMode::kSrc: {
122             /*
123                 should I worry about dithering for the lower depths?
124             */
125             SkPMColor pmc = SkPreMultiplyColor(color);
126             switch (dst.colorType()) {
127                 case kN32_SkColorType:
128                     if (data) {
129                         *data = pmc;
130                     }
131 //                    SkDebugf("--- D32_Src_BitmapXferProc\n");
132                     return D32_Src_BitmapXferProc;
133                 case kRGB_565_SkColorType:
134                     if (data) {
135                         *data = SkPixel32ToPixel16(pmc);
136                     }
137 //                    SkDebugf("--- D16_Src_BitmapXferProc\n");
138                     return D16_Src_BitmapXferProc;
139                 case kAlpha_8_SkColorType:
140                     if (data) {
141                         *data = SkGetPackedA32(pmc);
142                     }
143 //                    SkDebugf("--- DA8_Src_BitmapXferProc\n");
144                     return DA8_Src_BitmapXferProc;
145                 default:
146                     break;
147             }
148             break;
149         }
150         default:
151             break;
152     }
153     return nullptr;
154 }
155 
CallBitmapXferProc(const SkPixmap & dst,const SkIRect & rect,BitmapXferProc proc,uint32_t procData)156 static void CallBitmapXferProc(const SkPixmap& dst, const SkIRect& rect, BitmapXferProc proc,
157                                uint32_t procData) {
158     int shiftPerPixel;
159     switch (dst.colorType()) {
160         case kN32_SkColorType:
161             shiftPerPixel = 2;
162             break;
163         case kRGB_565_SkColorType:
164             shiftPerPixel = 1;
165             break;
166         case kAlpha_8_SkColorType:
167             shiftPerPixel = 0;
168             break;
169         default:
170             SkDEBUGFAIL("Can't use xferproc on this config");
171             return;
172     }
173 
174     uint8_t* pixels = (uint8_t*)dst.writable_addr();
175     SkASSERT(pixels);
176     const size_t rowBytes = dst.rowBytes();
177     const int widthBytes = rect.width() << shiftPerPixel;
178 
179     // skip down to the first scanline and X position
180     pixels += rect.fTop * rowBytes + (rect.fLeft << shiftPerPixel);
181     for (int scans = rect.height() - 1; scans >= 0; --scans) {
182         proc(pixels, widthBytes, procData);
183         pixels += rowBytes;
184     }
185 }
186 
drawPaint(const SkPaint & paint) const187 void SkDraw::drawPaint(const SkPaint& paint) const {
188     SkDEBUGCODE(this->validate();)
189 
190     if (fRC->isEmpty()) {
191         return;
192     }
193 
194     SkIRect    devRect;
195     devRect.set(0, 0, fDst.width(), fDst.height());
196 
197     if (fRC->isBW()) {
198         /*  If we don't have a shader (i.e. we're just a solid color) we may
199             be faster to operate directly on the device bitmap, rather than invoking
200             a blitter. Esp. true for xfermodes, which require a colorshader to be
201             present, which is just redundant work. Since we're drawing everywhere
202             in the clip, we don't have to worry about antialiasing.
203         */
204         uint32_t procData = 0;  // to avoid the warning
205         BitmapXferProc proc = ChooseBitmapXferProc(fDst, paint, &procData);
206         if (proc) {
207             if (D_Dst_BitmapXferProc == proc) { // nothing to do
208                 return;
209             }
210 
211             SkRegion::Iterator iter(fRC->bwRgn());
212             while (!iter.done()) {
213                 CallBitmapXferProc(fDst, iter.rect(), proc, procData);
214                 iter.next();
215             }
216             return;
217         }
218     }
219 
220     // normal case: use a blitter
221     SkAutoBlitterChoose blitter(fDst, *fMatrix, paint);
222     SkScan::FillIRect(devRect, *fRC, blitter.get());
223 }
224 
225 ///////////////////////////////////////////////////////////////////////////////
226 
227 struct PtProcRec {
228     SkCanvas::PointMode fMode;
229     const SkPaint*  fPaint;
230     const SkRegion* fClip;
231     const SkRasterClip* fRC;
232 
233     // computed values
234     SkFixed fRadius;
235 
236     typedef void (*Proc)(const PtProcRec&, const SkPoint devPts[], int count,
237                          SkBlitter*);
238 
239     bool init(SkCanvas::PointMode, const SkPaint&, const SkMatrix* matrix,
240               const SkRasterClip*);
241     Proc chooseProc(SkBlitter** blitter);
242 
243 private:
244     SkAAClipBlitterWrapper fWrapper;
245 };
246 
bw_pt_rect_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)247 static void bw_pt_rect_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
248                                  int count, SkBlitter* blitter) {
249     SkASSERT(rec.fClip->isRect());
250     const SkIRect& r = rec.fClip->getBounds();
251 
252     for (int i = 0; i < count; i++) {
253         int x = SkScalarFloorToInt(devPts[i].fX);
254         int y = SkScalarFloorToInt(devPts[i].fY);
255         if (r.contains(x, y)) {
256             blitter->blitH(x, y, 1);
257         }
258     }
259 }
260 
bw_pt_rect_16_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)261 static void bw_pt_rect_16_hair_proc(const PtProcRec& rec,
262                                     const SkPoint devPts[], int count,
263                                     SkBlitter* blitter) {
264     SkASSERT(rec.fRC->isRect());
265     const SkIRect& r = rec.fRC->getBounds();
266     uint32_t value;
267     const SkPixmap* dst = blitter->justAnOpaqueColor(&value);
268     SkASSERT(dst);
269 
270     uint16_t* addr = dst->writable_addr16(0, 0);
271     size_t    rb = dst->rowBytes();
272 
273     for (int i = 0; i < count; i++) {
274         int x = SkScalarFloorToInt(devPts[i].fX);
275         int y = SkScalarFloorToInt(devPts[i].fY);
276         if (r.contains(x, y)) {
277             ((uint16_t*)((char*)addr + y * rb))[x] = SkToU16(value);
278         }
279     }
280 }
281 
bw_pt_rect_32_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)282 static void bw_pt_rect_32_hair_proc(const PtProcRec& rec,
283                                     const SkPoint devPts[], int count,
284                                     SkBlitter* blitter) {
285     SkASSERT(rec.fRC->isRect());
286     const SkIRect& r = rec.fRC->getBounds();
287     uint32_t value;
288     const SkPixmap* dst = blitter->justAnOpaqueColor(&value);
289     SkASSERT(dst);
290 
291     SkPMColor* addr = dst->writable_addr32(0, 0);
292     size_t     rb = dst->rowBytes();
293 
294     for (int i = 0; i < count; i++) {
295         int x = SkScalarFloorToInt(devPts[i].fX);
296         int y = SkScalarFloorToInt(devPts[i].fY);
297         if (r.contains(x, y)) {
298             ((SkPMColor*)((char*)addr + y * rb))[x] = value;
299         }
300     }
301 }
302 
bw_pt_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)303 static void bw_pt_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
304                             int count, SkBlitter* blitter) {
305     for (int i = 0; i < count; i++) {
306         int x = SkScalarFloorToInt(devPts[i].fX);
307         int y = SkScalarFloorToInt(devPts[i].fY);
308         if (rec.fClip->contains(x, y)) {
309             blitter->blitH(x, y, 1);
310         }
311     }
312 }
313 
bw_line_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)314 static void bw_line_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
315                               int count, SkBlitter* blitter) {
316     for (int i = 0; i < count; i += 2) {
317         SkScan::HairLine(&devPts[i], 2, *rec.fRC, blitter);
318     }
319 }
320 
bw_poly_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)321 static void bw_poly_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
322                               int count, SkBlitter* blitter) {
323     SkScan::HairLine(devPts, count, *rec.fRC, blitter);
324 }
325 
326 // aa versions
327 
aa_line_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)328 static void aa_line_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
329                               int count, SkBlitter* blitter) {
330     for (int i = 0; i < count; i += 2) {
331         SkScan::AntiHairLine(&devPts[i], 2, *rec.fRC, blitter);
332     }
333 }
334 
aa_poly_hair_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)335 static void aa_poly_hair_proc(const PtProcRec& rec, const SkPoint devPts[],
336                               int count, SkBlitter* blitter) {
337     SkScan::AntiHairLine(devPts, count, *rec.fRC, blitter);
338 }
339 
340 // square procs (strokeWidth > 0 but matrix is square-scale (sx == sy)
341 
bw_square_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)342 static void bw_square_proc(const PtProcRec& rec, const SkPoint devPts[],
343                            int count, SkBlitter* blitter) {
344     const SkFixed radius = rec.fRadius;
345     for (int i = 0; i < count; i++) {
346         SkFixed x = SkScalarToFixed(devPts[i].fX);
347         SkFixed y = SkScalarToFixed(devPts[i].fY);
348 
349         SkXRect r;
350         r.fLeft = x - radius;
351         r.fTop = y - radius;
352         r.fRight = x + radius;
353         r.fBottom = y + radius;
354 
355         SkScan::FillXRect(r, *rec.fRC, blitter);
356     }
357 }
358 
aa_square_proc(const PtProcRec & rec,const SkPoint devPts[],int count,SkBlitter * blitter)359 static void aa_square_proc(const PtProcRec& rec, const SkPoint devPts[],
360                            int count, SkBlitter* blitter) {
361     const SkFixed radius = rec.fRadius;
362     for (int i = 0; i < count; i++) {
363         SkFixed x = SkScalarToFixed(devPts[i].fX);
364         SkFixed y = SkScalarToFixed(devPts[i].fY);
365 
366         SkXRect r;
367         r.fLeft = x - radius;
368         r.fTop = y - radius;
369         r.fRight = x + radius;
370         r.fBottom = y + radius;
371 
372         SkScan::AntiFillXRect(r, *rec.fRC, blitter);
373     }
374 }
375 
376 // If this guy returns true, then chooseProc() must return a valid proc
init(SkCanvas::PointMode mode,const SkPaint & paint,const SkMatrix * matrix,const SkRasterClip * rc)377 bool PtProcRec::init(SkCanvas::PointMode mode, const SkPaint& paint,
378                      const SkMatrix* matrix, const SkRasterClip* rc) {
379     if ((unsigned)mode > (unsigned)SkCanvas::kPolygon_PointMode) {
380         return false;
381     }
382 
383     if (paint.getPathEffect()) {
384         return false;
385     }
386     SkScalar width = paint.getStrokeWidth();
387     if (0 == width) {
388         fMode = mode;
389         fPaint = &paint;
390         fClip = nullptr;
391         fRC = rc;
392         fRadius = SK_FixedHalf;
393         return true;
394     }
395     if (paint.getStrokeCap() != SkPaint::kRound_Cap &&
396         matrix->isScaleTranslate() && SkCanvas::kPoints_PointMode == mode) {
397         SkScalar sx = matrix->get(SkMatrix::kMScaleX);
398         SkScalar sy = matrix->get(SkMatrix::kMScaleY);
399         if (SkScalarNearlyZero(sx - sy)) {
400             if (sx < 0) {
401                 sx = -sx;
402             }
403 
404             fMode = mode;
405             fPaint = &paint;
406             fClip = nullptr;
407             fRC = rc;
408             fRadius = SkScalarToFixed(width * sx) >> 1;
409             return true;
410         }
411     }
412     return false;
413 }
414 
chooseProc(SkBlitter ** blitterPtr)415 PtProcRec::Proc PtProcRec::chooseProc(SkBlitter** blitterPtr) {
416     Proc proc = nullptr;
417 
418     SkBlitter* blitter = *blitterPtr;
419     if (fRC->isBW()) {
420         fClip = &fRC->bwRgn();
421     } else {
422         fWrapper.init(*fRC, blitter);
423         fClip = &fWrapper.getRgn();
424         blitter = fWrapper.getBlitter();
425         *blitterPtr = blitter;
426     }
427 
428     // for our arrays
429     SkASSERT(0 == SkCanvas::kPoints_PointMode);
430     SkASSERT(1 == SkCanvas::kLines_PointMode);
431     SkASSERT(2 == SkCanvas::kPolygon_PointMode);
432     SkASSERT((unsigned)fMode <= (unsigned)SkCanvas::kPolygon_PointMode);
433 
434     if (fPaint->isAntiAlias()) {
435         if (0 == fPaint->getStrokeWidth()) {
436             static const Proc gAAProcs[] = {
437                 aa_square_proc, aa_line_hair_proc, aa_poly_hair_proc
438             };
439             proc = gAAProcs[fMode];
440         } else if (fPaint->getStrokeCap() != SkPaint::kRound_Cap) {
441             SkASSERT(SkCanvas::kPoints_PointMode == fMode);
442             proc = aa_square_proc;
443         }
444     } else {    // BW
445         if (fRadius <= SK_FixedHalf) {    // small radii and hairline
446             if (SkCanvas::kPoints_PointMode == fMode && fClip->isRect()) {
447                 uint32_t value;
448                 const SkPixmap* bm = blitter->justAnOpaqueColor(&value);
449                 if (bm && kRGB_565_SkColorType == bm->colorType()) {
450                     proc = bw_pt_rect_16_hair_proc;
451                 } else if (bm && kN32_SkColorType == bm->colorType()) {
452                     proc = bw_pt_rect_32_hair_proc;
453                 } else {
454                     proc = bw_pt_rect_hair_proc;
455                 }
456             } else {
457                 static Proc gBWProcs[] = {
458                     bw_pt_hair_proc, bw_line_hair_proc, bw_poly_hair_proc
459                 };
460                 proc = gBWProcs[fMode];
461             }
462         } else {
463             proc = bw_square_proc;
464         }
465     }
466     return proc;
467 }
468 
469 // each of these costs 8-bytes of stack space, so don't make it too large
470 // must be even for lines/polygon to work
471 #define MAX_DEV_PTS     32
472 
drawPoints(SkCanvas::PointMode mode,size_t count,const SkPoint pts[],const SkPaint & paint,SkBaseDevice * device) const473 void SkDraw::drawPoints(SkCanvas::PointMode mode, size_t count,
474                         const SkPoint pts[], const SkPaint& paint,
475                         SkBaseDevice* device) const {
476     // if we're in lines mode, force count to be even
477     if (SkCanvas::kLines_PointMode == mode) {
478         count &= ~(size_t)1;
479     }
480 
481     if ((long)count <= 0) {
482         return;
483     }
484 
485     SkASSERT(pts != nullptr);
486     SkDEBUGCODE(this->validate();)
487 
488      // nothing to draw
489     if (fRC->isEmpty()) {
490         return;
491     }
492 
493     PtProcRec rec;
494     if (!device && rec.init(mode, paint, fMatrix, fRC)) {
495         SkAutoBlitterChoose blitter(fDst, *fMatrix, paint);
496 
497         SkPoint             devPts[MAX_DEV_PTS];
498         const SkMatrix*     matrix = fMatrix;
499         SkBlitter*          bltr = blitter.get();
500         PtProcRec::Proc     proc = rec.chooseProc(&bltr);
501         // we have to back up subsequent passes if we're in polygon mode
502         const size_t backup = (SkCanvas::kPolygon_PointMode == mode);
503 
504         do {
505             int n = SkToInt(count);
506             if (n > MAX_DEV_PTS) {
507                 n = MAX_DEV_PTS;
508             }
509             matrix->mapPoints(devPts, pts, n);
510             proc(rec, devPts, n, bltr);
511             pts += n - backup;
512             SkASSERT(SkToInt(count) >= n);
513             count -= n;
514             if (count > 0) {
515                 count += backup;
516             }
517         } while (count != 0);
518     } else {
519         switch (mode) {
520             case SkCanvas::kPoints_PointMode: {
521                 // temporarily mark the paint as filling.
522                 SkPaint newPaint(paint);
523                 newPaint.setStyle(SkPaint::kFill_Style);
524 
525                 SkScalar width = newPaint.getStrokeWidth();
526                 SkScalar radius = SkScalarHalf(width);
527 
528                 if (newPaint.getStrokeCap() == SkPaint::kRound_Cap) {
529                     SkPath      path;
530                     SkMatrix    preMatrix;
531 
532                     path.addCircle(0, 0, radius);
533                     for (size_t i = 0; i < count; i++) {
534                         preMatrix.setTranslate(pts[i].fX, pts[i].fY);
535                         // pass true for the last point, since we can modify
536                         // then path then
537                         path.setIsVolatile((count-1) == i);
538                         if (device) {
539                             device->drawPath(path, newPaint, &preMatrix, (count-1) == i);
540                         } else {
541                             this->drawPath(path, newPaint, &preMatrix, (count-1) == i);
542                         }
543                     }
544                 } else {
545                     SkRect  r;
546 
547                     for (size_t i = 0; i < count; i++) {
548                         r.fLeft = pts[i].fX - radius;
549                         r.fTop = pts[i].fY - radius;
550                         r.fRight = r.fLeft + width;
551                         r.fBottom = r.fTop + width;
552                         if (device) {
553                             device->drawRect(r, newPaint);
554                         } else {
555                             this->drawRect(r, newPaint);
556                         }
557                     }
558                 }
559                 break;
560             }
561             case SkCanvas::kLines_PointMode:
562                 if (2 == count && paint.getPathEffect()) {
563                     // most likely a dashed line - see if it is one of the ones
564                     // we can accelerate
565                     SkStrokeRec rec(paint);
566                     SkPathEffect::PointData pointData;
567 
568                     SkPath path;
569                     path.moveTo(pts[0]);
570                     path.lineTo(pts[1]);
571 
572                     SkRect cullRect = SkRect::Make(fRC->getBounds());
573 
574                     if (paint.getPathEffect()->asPoints(&pointData, path, rec,
575                                                         *fMatrix, &cullRect)) {
576                         // 'asPoints' managed to find some fast path
577 
578                         SkPaint newP(paint);
579                         newP.setPathEffect(nullptr);
580                         newP.setStyle(SkPaint::kFill_Style);
581 
582                         if (!pointData.fFirst.isEmpty()) {
583                             if (device) {
584                                 device->drawPath(pointData.fFirst, newP);
585                             } else {
586                                 this->drawPath(pointData.fFirst, newP);
587                             }
588                         }
589 
590                         if (!pointData.fLast.isEmpty()) {
591                             if (device) {
592                                 device->drawPath(pointData.fLast, newP);
593                             } else {
594                                 this->drawPath(pointData.fLast, newP);
595                             }
596                         }
597 
598                         if (pointData.fSize.fX == pointData.fSize.fY) {
599                             // The rest of the dashed line can just be drawn as points
600                             SkASSERT(pointData.fSize.fX == SkScalarHalf(newP.getStrokeWidth()));
601 
602                             if (SkPathEffect::PointData::kCircles_PointFlag & pointData.fFlags) {
603                                 newP.setStrokeCap(SkPaint::kRound_Cap);
604                             } else {
605                                 newP.setStrokeCap(SkPaint::kButt_Cap);
606                             }
607 
608                             if (device) {
609                                 device->drawPoints(SkCanvas::kPoints_PointMode,
610                                                    pointData.fNumPoints,
611                                                    pointData.fPoints,
612                                                    newP);
613                             } else {
614                                 this->drawPoints(SkCanvas::kPoints_PointMode,
615                                                  pointData.fNumPoints,
616                                                  pointData.fPoints,
617                                                  newP,
618                                                  device);
619                             }
620                             break;
621                         } else {
622                             // The rest of the dashed line must be drawn as rects
623                             SkASSERT(!(SkPathEffect::PointData::kCircles_PointFlag &
624                                       pointData.fFlags));
625 
626                             SkRect r;
627 
628                             for (int i = 0; i < pointData.fNumPoints; ++i) {
629                                 r.set(pointData.fPoints[i].fX - pointData.fSize.fX,
630                                       pointData.fPoints[i].fY - pointData.fSize.fY,
631                                       pointData.fPoints[i].fX + pointData.fSize.fX,
632                                       pointData.fPoints[i].fY + pointData.fSize.fY);
633                                 if (device) {
634                                     device->drawRect(r, newP);
635                                 } else {
636                                     this->drawRect(r, newP);
637                                 }
638                             }
639                         }
640 
641                         break;
642                     }
643                 }
644                 // couldn't take fast path so fall through!
645             case SkCanvas::kPolygon_PointMode: {
646                 count -= 1;
647                 SkPath path;
648                 SkPaint p(paint);
649                 p.setStyle(SkPaint::kStroke_Style);
650                 size_t inc = (SkCanvas::kLines_PointMode == mode) ? 2 : 1;
651                 path.setIsVolatile(true);
652                 for (size_t i = 0; i < count; i += inc) {
653                     path.moveTo(pts[i]);
654                     path.lineTo(pts[i+1]);
655                     if (device) {
656                         device->drawPath(path, p, nullptr, true);
657                     } else {
658                         this->drawPath(path, p, nullptr, true);
659                     }
660                     path.rewind();
661                 }
662                 break;
663             }
664         }
665     }
666 }
667 
compute_stroke_size(const SkPaint & paint,const SkMatrix & matrix)668 static inline SkPoint compute_stroke_size(const SkPaint& paint, const SkMatrix& matrix) {
669     SkASSERT(matrix.rectStaysRect());
670     SkASSERT(SkPaint::kFill_Style != paint.getStyle());
671 
672     SkVector size;
673     SkPoint pt = { paint.getStrokeWidth(), paint.getStrokeWidth() };
674     matrix.mapVectors(&size, &pt, 1);
675     return SkPoint::Make(SkScalarAbs(size.fX), SkScalarAbs(size.fY));
676 }
677 
easy_rect_join(const SkPaint & paint,const SkMatrix & matrix,SkPoint * strokeSize)678 static bool easy_rect_join(const SkPaint& paint, const SkMatrix& matrix,
679                            SkPoint* strokeSize) {
680     if (SkPaint::kMiter_Join != paint.getStrokeJoin() ||
681         paint.getStrokeMiter() < SK_ScalarSqrt2) {
682         return false;
683     }
684 
685     *strokeSize = compute_stroke_size(paint, matrix);
686     return true;
687 }
688 
ComputeRectType(const SkPaint & paint,const SkMatrix & matrix,SkPoint * strokeSize)689 SkDraw::RectType SkDraw::ComputeRectType(const SkPaint& paint,
690                                          const SkMatrix& matrix,
691                                          SkPoint* strokeSize) {
692     RectType rtype;
693     const SkScalar width = paint.getStrokeWidth();
694     const bool zeroWidth = (0 == width);
695     SkPaint::Style style = paint.getStyle();
696 
697     if ((SkPaint::kStrokeAndFill_Style == style) && zeroWidth) {
698         style = SkPaint::kFill_Style;
699     }
700 
701     if (paint.getPathEffect() || paint.getMaskFilter() ||
702         paint.getRasterizer() || !matrix.rectStaysRect() ||
703         SkPaint::kStrokeAndFill_Style == style) {
704         rtype = kPath_RectType;
705     } else if (SkPaint::kFill_Style == style) {
706         rtype = kFill_RectType;
707     } else if (zeroWidth) {
708         rtype = kHair_RectType;
709     } else if (easy_rect_join(paint, matrix, strokeSize)) {
710         rtype = kStroke_RectType;
711     } else {
712         rtype = kPath_RectType;
713     }
714     return rtype;
715 }
716 
rect_points(const SkRect & r)717 static const SkPoint* rect_points(const SkRect& r) {
718     return SkTCast<const SkPoint*>(&r);
719 }
720 
rect_points(SkRect & r)721 static SkPoint* rect_points(SkRect& r) {
722     return SkTCast<SkPoint*>(&r);
723 }
724 
drawRect(const SkRect & prePaintRect,const SkPaint & paint,const SkMatrix * paintMatrix,const SkRect * postPaintRect) const725 void SkDraw::drawRect(const SkRect& prePaintRect, const SkPaint& paint,
726                       const SkMatrix* paintMatrix, const SkRect* postPaintRect) const {
727     SkDEBUGCODE(this->validate();)
728 
729     // nothing to draw
730     if (fRC->isEmpty()) {
731         return;
732     }
733 
734     const SkMatrix* matrix;
735     SkMatrix combinedMatrixStorage;
736     if (paintMatrix) {
737         SkASSERT(postPaintRect);
738         combinedMatrixStorage.setConcat(*fMatrix, *paintMatrix);
739         matrix = &combinedMatrixStorage;
740     } else {
741         SkASSERT(!postPaintRect);
742         matrix = fMatrix;
743     }
744 
745     SkPoint strokeSize;
746     RectType rtype = ComputeRectType(paint, *fMatrix, &strokeSize);
747 
748     if (kPath_RectType == rtype) {
749         SkDraw draw(*this);
750         if (paintMatrix) {
751             draw.fMatrix = matrix;
752         }
753         SkPath  tmp;
754         tmp.addRect(prePaintRect);
755         tmp.setFillType(SkPath::kWinding_FillType);
756         draw.drawPath(tmp, paint, nullptr, true);
757         return;
758     }
759 
760     SkRect devRect;
761     const SkRect& paintRect = paintMatrix ? *postPaintRect : prePaintRect;
762     // skip the paintMatrix when transforming the rect by the CTM
763     fMatrix->mapPoints(rect_points(devRect), rect_points(paintRect), 2);
764     devRect.sort();
765 
766     // look for the quick exit, before we build a blitter
767     SkRect bbox = devRect;
768     if (paint.getStyle() != SkPaint::kFill_Style) {
769         // extra space for hairlines
770         if (paint.getStrokeWidth() == 0) {
771             bbox.outset(1, 1);
772         } else {
773             // For kStroke_RectType, strokeSize is already computed.
774             const SkPoint& ssize = (kStroke_RectType == rtype)
775                 ? strokeSize
776                 : compute_stroke_size(paint, *fMatrix);
777             bbox.outset(SkScalarHalf(ssize.x()), SkScalarHalf(ssize.y()));
778         }
779     }
780 
781     SkIRect ir = bbox.roundOut();
782     if (fRC->quickReject(ir)) {
783         return;
784     }
785 
786     SkDeviceLooper looper(fDst, *fRC, ir, paint.isAntiAlias());
787     while (looper.next()) {
788         SkRect localDevRect;
789         looper.mapRect(&localDevRect, devRect);
790         SkMatrix localMatrix;
791         looper.mapMatrix(&localMatrix, *matrix);
792 
793         SkAutoBlitterChoose blitterStorage(looper.getPixmap(), localMatrix, paint);
794         const SkRasterClip& clip = looper.getRC();
795         SkBlitter*          blitter = blitterStorage.get();
796 
797         // we want to "fill" if we are kFill or kStrokeAndFill, since in the latter
798         // case we are also hairline (if we've gotten to here), which devolves to
799         // effectively just kFill
800         switch (rtype) {
801             case kFill_RectType:
802                 if (paint.isAntiAlias()) {
803                     SkScan::AntiFillRect(localDevRect, clip, blitter);
804                 } else {
805                     SkScan::FillRect(localDevRect, clip, blitter);
806                 }
807                 break;
808             case kStroke_RectType:
809                 if (paint.isAntiAlias()) {
810                     SkScan::AntiFrameRect(localDevRect, strokeSize, clip, blitter);
811                 } else {
812                     SkScan::FrameRect(localDevRect, strokeSize, clip, blitter);
813                 }
814                 break;
815             case kHair_RectType:
816                 if (paint.isAntiAlias()) {
817                     SkScan::AntiHairRect(localDevRect, clip, blitter);
818                 } else {
819                     SkScan::HairRect(localDevRect, clip, blitter);
820                 }
821                 break;
822             default:
823                 SkDEBUGFAIL("bad rtype");
824         }
825     }
826 }
827 
drawDevMask(const SkMask & srcM,const SkPaint & paint) const828 void SkDraw::drawDevMask(const SkMask& srcM, const SkPaint& paint) const {
829     if (srcM.fBounds.isEmpty()) {
830         return;
831     }
832 
833     const SkMask* mask = &srcM;
834 
835     SkMask dstM;
836     if (paint.getMaskFilter() &&
837         paint.getMaskFilter()->filterMask(&dstM, srcM, *fMatrix, nullptr)) {
838         mask = &dstM;
839     }
840     SkAutoMaskFreeImage ami(dstM.fImage);
841 
842     SkAutoBlitterChoose blitterChooser(fDst, *fMatrix, paint);
843     SkBlitter* blitter = blitterChooser.get();
844 
845     SkAAClipBlitterWrapper wrapper;
846     const SkRegion* clipRgn;
847 
848     if (fRC->isBW()) {
849         clipRgn = &fRC->bwRgn();
850     } else {
851         wrapper.init(*fRC, blitter);
852         clipRgn = &wrapper.getRgn();
853         blitter = wrapper.getBlitter();
854     }
855     blitter->blitMaskRegion(*mask, *clipRgn);
856 }
857 
fast_len(const SkVector & vec)858 static SkScalar fast_len(const SkVector& vec) {
859     SkScalar x = SkScalarAbs(vec.fX);
860     SkScalar y = SkScalarAbs(vec.fY);
861     if (x < y) {
862         SkTSwap(x, y);
863     }
864     return x + SkScalarHalf(y);
865 }
866 
SkDrawTreatAAStrokeAsHairline(SkScalar strokeWidth,const SkMatrix & matrix,SkScalar * coverage)867 bool SkDrawTreatAAStrokeAsHairline(SkScalar strokeWidth, const SkMatrix& matrix,
868                                    SkScalar* coverage) {
869     SkASSERT(strokeWidth > 0);
870     // We need to try to fake a thick-stroke with a modulated hairline.
871 
872     if (matrix.hasPerspective()) {
873         return false;
874     }
875 
876     SkVector src[2], dst[2];
877     src[0].set(strokeWidth, 0);
878     src[1].set(0, strokeWidth);
879     matrix.mapVectors(dst, src, 2);
880     SkScalar len0 = fast_len(dst[0]);
881     SkScalar len1 = fast_len(dst[1]);
882     if (len0 <= SK_Scalar1 && len1 <= SK_Scalar1) {
883         if (coverage) {
884             *coverage = SkScalarAve(len0, len1);
885         }
886         return true;
887     }
888     return false;
889 }
890 
drawRRect(const SkRRect & rrect,const SkPaint & paint) const891 void SkDraw::drawRRect(const SkRRect& rrect, const SkPaint& paint) const {
892     SkDEBUGCODE(this->validate());
893 
894     if (fRC->isEmpty()) {
895         return;
896     }
897 
898     {
899         // TODO: Investigate optimizing these options. They are in the same
900         // order as SkDraw::drawPath, which handles each case. It may be
901         // that there is no way to optimize for these using the SkRRect path.
902         SkScalar coverage;
903         if (SkDrawTreatAsHairline(paint, *fMatrix, &coverage)) {
904             goto DRAW_PATH;
905         }
906 
907         if (paint.getPathEffect() || paint.getStyle() != SkPaint::kFill_Style) {
908             goto DRAW_PATH;
909         }
910 
911         if (paint.getRasterizer()) {
912             goto DRAW_PATH;
913         }
914     }
915 
916     if (paint.getMaskFilter()) {
917         // Transform the rrect into device space.
918         SkRRect devRRect;
919         if (rrect.transform(*fMatrix, &devRRect)) {
920             SkAutoBlitterChoose blitter(fDst, *fMatrix, paint);
921             if (paint.getMaskFilter()->filterRRect(devRRect, *fMatrix, *fRC, blitter.get())) {
922                 return; // filterRRect() called the blitter, so we're done
923             }
924         }
925     }
926 
927 DRAW_PATH:
928     // Now fall back to the default case of using a path.
929     SkPath path;
930     path.addRRect(rrect);
931     this->drawPath(path, paint, nullptr, true);
932 }
933 
ComputeResScaleForStroking(const SkMatrix & matrix)934 SkScalar SkDraw::ComputeResScaleForStroking(const SkMatrix& matrix) {
935     if (!matrix.hasPerspective()) {
936         SkScalar sx = SkPoint::Length(matrix[SkMatrix::kMScaleX], matrix[SkMatrix::kMSkewY]);
937         SkScalar sy = SkPoint::Length(matrix[SkMatrix::kMSkewX],  matrix[SkMatrix::kMScaleY]);
938         if (SkScalarsAreFinite(sx, sy)) {
939             SkScalar scale = SkTMax(sx, sy);
940             if (scale > 0) {
941                 return scale;
942             }
943         }
944     }
945     return 1;
946 }
947 
drawDevPath(const SkPath & devPath,const SkPaint & paint,bool drawCoverage,SkBlitter * customBlitter,bool doFill) const948 void SkDraw::drawDevPath(const SkPath& devPath, const SkPaint& paint, bool drawCoverage,
949                          SkBlitter* customBlitter, bool doFill) const {
950     // Do a conservative quick-reject test, since a looper or other modifier may have moved us
951     // out of range.
952     if (!devPath.isInverseFillType()) {
953         // If we're a H or V line, our bounds will be empty. So we bloat here just so we don't
954         // appear empty to the intersects call. This also gives us slop in case we're antialiasing
955         SkRect pathBounds = devPath.getBounds().makeOutset(1, 1);
956 
957         if (paint.getMaskFilter()) {
958             paint.getMaskFilter()->computeFastBounds(pathBounds, &pathBounds);
959 
960             // Need to outset the path to work-around a bug in blurmaskfilter. When that is fixed
961             // we can remove this hack. See skbug.com/5542
962             pathBounds.outset(7, 7);
963         }
964 
965         // Now compare against the clip's bounds
966         if (!SkRect::Make(fRC->getBounds()).intersects(pathBounds)) {
967             return;
968         }
969     }
970 
971     SkBlitter* blitter = nullptr;
972     SkAutoBlitterChoose blitterStorage;
973     if (nullptr == customBlitter) {
974         blitterStorage.choose(fDst, *fMatrix, paint, drawCoverage);
975         blitter = blitterStorage.get();
976     } else {
977         blitter = customBlitter;
978     }
979 
980     if (paint.getMaskFilter()) {
981         SkStrokeRec::InitStyle style = doFill ? SkStrokeRec::kFill_InitStyle
982         : SkStrokeRec::kHairline_InitStyle;
983         if (paint.getMaskFilter()->filterPath(devPath, *fMatrix, *fRC, blitter, style)) {
984             return; // filterPath() called the blitter, so we're done
985         }
986     }
987 
988     void (*proc)(const SkPath&, const SkRasterClip&, SkBlitter*);
989     if (doFill) {
990         if (paint.isAntiAlias()) {
991             proc = SkScan::AntiFillPath;
992         } else {
993             proc = SkScan::FillPath;
994         }
995     } else {    // hairline
996         if (paint.isAntiAlias()) {
997             switch (paint.getStrokeCap()) {
998                 case SkPaint::kButt_Cap:
999                     proc = SkScan::AntiHairPath;
1000                     break;
1001                 case SkPaint::kSquare_Cap:
1002                     proc = SkScan::AntiHairSquarePath;
1003                     break;
1004                 case SkPaint::kRound_Cap:
1005                     proc = SkScan::AntiHairRoundPath;
1006                     break;
1007                 default:
1008                     proc SK_INIT_TO_AVOID_WARNING;
1009                     SkDEBUGFAIL("unknown paint cap type");
1010             }
1011         } else {
1012             switch (paint.getStrokeCap()) {
1013                 case SkPaint::kButt_Cap:
1014                     proc = SkScan::HairPath;
1015                     break;
1016                 case SkPaint::kSquare_Cap:
1017                     proc = SkScan::HairSquarePath;
1018                     break;
1019                 case SkPaint::kRound_Cap:
1020                     proc = SkScan::HairRoundPath;
1021                     break;
1022                 default:
1023                     proc SK_INIT_TO_AVOID_WARNING;
1024                     SkDEBUGFAIL("unknown paint cap type");
1025             }
1026         }
1027     }
1028     proc(devPath, *fRC, blitter);
1029 }
1030 
drawPath(const SkPath & origSrcPath,const SkPaint & origPaint,const SkMatrix * prePathMatrix,bool pathIsMutable,bool drawCoverage,SkBlitter * customBlitter) const1031 void SkDraw::drawPath(const SkPath& origSrcPath, const SkPaint& origPaint,
1032                       const SkMatrix* prePathMatrix, bool pathIsMutable,
1033                       bool drawCoverage, SkBlitter* customBlitter) const {
1034     SkDEBUGCODE(this->validate();)
1035 
1036     // nothing to draw
1037     if (fRC->isEmpty()) {
1038         return;
1039     }
1040 
1041     SkPath*         pathPtr = (SkPath*)&origSrcPath;
1042     bool            doFill = true;
1043     SkPath          tmpPath;
1044     SkMatrix        tmpMatrix;
1045     const SkMatrix* matrix = fMatrix;
1046     tmpPath.setIsVolatile(true);
1047 
1048     if (prePathMatrix) {
1049         if (origPaint.getPathEffect() || origPaint.getStyle() != SkPaint::kFill_Style ||
1050                 origPaint.getRasterizer()) {
1051             SkPath* result = pathPtr;
1052 
1053             if (!pathIsMutable) {
1054                 result = &tmpPath;
1055                 pathIsMutable = true;
1056             }
1057             pathPtr->transform(*prePathMatrix, result);
1058             pathPtr = result;
1059         } else {
1060             tmpMatrix.setConcat(*matrix, *prePathMatrix);
1061             matrix = &tmpMatrix;
1062         }
1063     }
1064     // at this point we're done with prePathMatrix
1065     SkDEBUGCODE(prePathMatrix = (const SkMatrix*)0x50FF8001;)
1066 
1067     SkTCopyOnFirstWrite<SkPaint> paint(origPaint);
1068 
1069     {
1070         SkScalar coverage;
1071         if (SkDrawTreatAsHairline(origPaint, *matrix, &coverage)) {
1072             if (SK_Scalar1 == coverage) {
1073                 paint.writable()->setStrokeWidth(0);
1074             } else if (SkBlendMode_SupportsCoverageAsAlpha(origPaint.getBlendMode())) {
1075                 U8CPU newAlpha;
1076 #if 0
1077                 newAlpha = SkToU8(SkScalarRoundToInt(coverage *
1078                                                      origPaint.getAlpha()));
1079 #else
1080                 // this is the old technique, which we preserve for now so
1081                 // we don't change previous results (testing)
1082                 // the new way seems fine, its just (a tiny bit) different
1083                 int scale = (int)(coverage * 256);
1084                 newAlpha = origPaint.getAlpha() * scale >> 8;
1085 #endif
1086                 SkPaint* writablePaint = paint.writable();
1087                 writablePaint->setStrokeWidth(0);
1088                 writablePaint->setAlpha(newAlpha);
1089             }
1090         }
1091     }
1092 
1093     if (paint->getPathEffect() || paint->getStyle() != SkPaint::kFill_Style) {
1094         SkRect cullRect;
1095         const SkRect* cullRectPtr = nullptr;
1096         if (this->computeConservativeLocalClipBounds(&cullRect)) {
1097             cullRectPtr = &cullRect;
1098         }
1099         doFill = paint->getFillPath(*pathPtr, &tmpPath, cullRectPtr,
1100                                     ComputeResScaleForStroking(*fMatrix));
1101         pathPtr = &tmpPath;
1102     }
1103 
1104     if (paint->getRasterizer()) {
1105         SkMask  mask;
1106         if (paint->getRasterizer()->rasterize(*pathPtr, *matrix,
1107                             &fRC->getBounds(), paint->getMaskFilter(), &mask,
1108                             SkMask::kComputeBoundsAndRenderImage_CreateMode)) {
1109             this->drawDevMask(mask, *paint);
1110             SkMask::FreeImage(mask.fImage);
1111         }
1112         return;
1113     }
1114 
1115     // avoid possibly allocating a new path in transform if we can
1116     SkPath* devPathPtr = pathIsMutable ? pathPtr : &tmpPath;
1117 
1118     // transform the path into device space
1119     pathPtr->transform(*matrix, devPathPtr);
1120 
1121     this->drawDevPath(*devPathPtr, *paint, drawCoverage, customBlitter, doFill);
1122 }
1123 
drawBitmapAsMask(const SkBitmap & bitmap,const SkPaint & paint) const1124 void SkDraw::drawBitmapAsMask(const SkBitmap& bitmap, const SkPaint& paint) const {
1125     SkASSERT(bitmap.colorType() == kAlpha_8_SkColorType);
1126 
1127     if (SkTreatAsSprite(*fMatrix, bitmap.dimensions(), paint)) {
1128         int ix = SkScalarRoundToInt(fMatrix->getTranslateX());
1129         int iy = SkScalarRoundToInt(fMatrix->getTranslateY());
1130 
1131         SkPixmap pmap;
1132         if (!bitmap.peekPixels(&pmap)) {
1133             return;
1134         }
1135         SkMask  mask;
1136         mask.fBounds.set(ix, iy, ix + pmap.width(), iy + pmap.height());
1137         mask.fFormat = SkMask::kA8_Format;
1138         mask.fRowBytes = SkToU32(pmap.rowBytes());
1139         // fImage is typed as writable, but in this case it is used read-only
1140         mask.fImage = (uint8_t*)pmap.addr8(0, 0);
1141 
1142         this->drawDevMask(mask, paint);
1143     } else {    // need to xform the bitmap first
1144         SkRect  r;
1145         SkMask  mask;
1146 
1147         r.set(0, 0,
1148               SkIntToScalar(bitmap.width()), SkIntToScalar(bitmap.height()));
1149         fMatrix->mapRect(&r);
1150         r.round(&mask.fBounds);
1151 
1152         // set the mask's bounds to the transformed bitmap-bounds,
1153         // clipped to the actual device
1154         {
1155             SkIRect    devBounds;
1156             devBounds.set(0, 0, fDst.width(), fDst.height());
1157             // need intersect(l, t, r, b) on irect
1158             if (!mask.fBounds.intersect(devBounds)) {
1159                 return;
1160             }
1161         }
1162 
1163         mask.fFormat = SkMask::kA8_Format;
1164         mask.fRowBytes = SkAlign4(mask.fBounds.width());
1165         size_t size = mask.computeImageSize();
1166         if (0 == size) {
1167             // the mask is too big to allocated, draw nothing
1168             return;
1169         }
1170 
1171         // allocate (and clear) our temp buffer to hold the transformed bitmap
1172         SkAutoTMalloc<uint8_t> storage(size);
1173         mask.fImage = storage.get();
1174         memset(mask.fImage, 0, size);
1175 
1176         // now draw our bitmap(src) into mask(dst), transformed by the matrix
1177         {
1178             SkBitmap    device;
1179             device.installPixels(SkImageInfo::MakeA8(mask.fBounds.width(), mask.fBounds.height()),
1180                                  mask.fImage, mask.fRowBytes);
1181 
1182             SkCanvas c(device);
1183             // need the unclipped top/left for the translate
1184             c.translate(-SkIntToScalar(mask.fBounds.fLeft),
1185                         -SkIntToScalar(mask.fBounds.fTop));
1186             c.concat(*fMatrix);
1187 
1188             // We can't call drawBitmap, or we'll infinitely recurse. Instead
1189             // we manually build a shader and draw that into our new mask
1190             SkPaint tmpPaint;
1191             tmpPaint.setFlags(paint.getFlags());
1192             tmpPaint.setFilterQuality(paint.getFilterQuality());
1193             SkPaint paintWithShader = make_paint_with_image(tmpPaint, bitmap);
1194             SkRect rr;
1195             rr.set(0, 0, SkIntToScalar(bitmap.width()),
1196                    SkIntToScalar(bitmap.height()));
1197             c.drawRect(rr, paintWithShader);
1198         }
1199         this->drawDevMask(mask, paint);
1200     }
1201 }
1202 
clipped_out(const SkMatrix & m,const SkRasterClip & c,const SkRect & srcR)1203 static bool clipped_out(const SkMatrix& m, const SkRasterClip& c,
1204                         const SkRect& srcR) {
1205     SkRect  dstR;
1206     m.mapRect(&dstR, srcR);
1207     return c.quickReject(dstR.roundOut());
1208 }
1209 
clipped_out(const SkMatrix & matrix,const SkRasterClip & clip,int width,int height)1210 static bool clipped_out(const SkMatrix& matrix, const SkRasterClip& clip,
1211                         int width, int height) {
1212     SkRect  r;
1213     r.set(0, 0, SkIntToScalar(width), SkIntToScalar(height));
1214     return clipped_out(matrix, clip, r);
1215 }
1216 
clipHandlesSprite(const SkRasterClip & clip,int x,int y,const SkPixmap & pmap)1217 static bool clipHandlesSprite(const SkRasterClip& clip, int x, int y, const SkPixmap& pmap) {
1218     return clip.isBW() || clip.quickContains(x, y, x + pmap.width(), y + pmap.height());
1219 }
1220 
drawBitmap(const SkBitmap & bitmap,const SkMatrix & prematrix,const SkRect * dstBounds,const SkPaint & origPaint) const1221 void SkDraw::drawBitmap(const SkBitmap& bitmap, const SkMatrix& prematrix,
1222                         const SkRect* dstBounds, const SkPaint& origPaint) const {
1223     SkDEBUGCODE(this->validate();)
1224 
1225     // nothing to draw
1226     if (fRC->isEmpty() ||
1227             bitmap.width() == 0 || bitmap.height() == 0 ||
1228             bitmap.colorType() == kUnknown_SkColorType) {
1229         return;
1230     }
1231 
1232     SkTCopyOnFirstWrite<SkPaint> paint(origPaint);
1233     if (origPaint.getStyle() != SkPaint::kFill_Style) {
1234         paint.writable()->setStyle(SkPaint::kFill_Style);
1235     }
1236 
1237     SkMatrix matrix;
1238     matrix.setConcat(*fMatrix, prematrix);
1239 
1240     if (clipped_out(matrix, *fRC, bitmap.width(), bitmap.height())) {
1241         return;
1242     }
1243 
1244     if (bitmap.colorType() != kAlpha_8_SkColorType
1245         && SkTreatAsSprite(matrix, bitmap.dimensions(), *paint)) {
1246         //
1247         // It is safe to call lock pixels now, since we know the matrix is
1248         // (more or less) identity.
1249         //
1250         SkPixmap pmap;
1251         if (!bitmap.peekPixels(&pmap)) {
1252             return;
1253         }
1254         int ix = SkScalarRoundToInt(matrix.getTranslateX());
1255         int iy = SkScalarRoundToInt(matrix.getTranslateY());
1256         if (clipHandlesSprite(*fRC, ix, iy, pmap)) {
1257             SkSTArenaAlloc<kSkBlitterContextSize> allocator;
1258             // blitter will be owned by the allocator.
1259             SkBlitter* blitter = SkBlitter::ChooseSprite(fDst, *paint, pmap, ix, iy, &allocator);
1260             if (blitter) {
1261                 SkScan::FillIRect(SkIRect::MakeXYWH(ix, iy, pmap.width(), pmap.height()),
1262                                   *fRC, blitter);
1263                 return;
1264             }
1265             // if !blitter, then we fall-through to the slower case
1266         }
1267     }
1268 
1269     // now make a temp draw on the stack, and use it
1270     //
1271     SkDraw draw(*this);
1272     draw.fMatrix = &matrix;
1273 
1274     if (bitmap.colorType() == kAlpha_8_SkColorType && !paint->getColorFilter()) {
1275         draw.drawBitmapAsMask(bitmap, *paint);
1276     } else {
1277         SkPaint paintWithShader = make_paint_with_image(*paint, bitmap);
1278         const SkRect srcBounds = SkRect::MakeIWH(bitmap.width(), bitmap.height());
1279         if (dstBounds) {
1280             this->drawRect(srcBounds, paintWithShader, &prematrix, dstBounds);
1281         } else {
1282             draw.drawRect(srcBounds, paintWithShader);
1283         }
1284     }
1285 }
1286 
drawSprite(const SkBitmap & bitmap,int x,int y,const SkPaint & origPaint) const1287 void SkDraw::drawSprite(const SkBitmap& bitmap, int x, int y, const SkPaint& origPaint) const {
1288     SkDEBUGCODE(this->validate();)
1289 
1290     // nothing to draw
1291     if (fRC->isEmpty() ||
1292             bitmap.width() == 0 || bitmap.height() == 0 ||
1293             bitmap.colorType() == kUnknown_SkColorType) {
1294         return;
1295     }
1296 
1297     const SkIRect bounds = SkIRect::MakeXYWH(x, y, bitmap.width(), bitmap.height());
1298 
1299     if (fRC->quickReject(bounds)) {
1300         return; // nothing to draw
1301     }
1302 
1303     SkPaint paint(origPaint);
1304     paint.setStyle(SkPaint::kFill_Style);
1305 
1306     SkPixmap pmap;
1307     if (!bitmap.peekPixels(&pmap)) {
1308         return;
1309     }
1310 
1311     if (nullptr == paint.getColorFilter() && clipHandlesSprite(*fRC, x, y, pmap)) {
1312         // blitter will be owned by the allocator.
1313         SkSTArenaAlloc<kSkBlitterContextSize> allocator;
1314         SkBlitter* blitter = SkBlitter::ChooseSprite(fDst, paint, pmap, x, y, &allocator);
1315         if (blitter) {
1316             SkScan::FillIRect(bounds, *fRC, blitter);
1317             return;
1318         }
1319     }
1320 
1321     SkMatrix        matrix;
1322     SkRect          r;
1323 
1324     // get a scalar version of our rect
1325     r.set(bounds);
1326 
1327     // create shader with offset
1328     matrix.setTranslate(r.fLeft, r.fTop);
1329     SkPaint paintWithShader = make_paint_with_image(paint, bitmap, &matrix);
1330     SkDraw draw(*this);
1331     matrix.reset();
1332     draw.fMatrix = &matrix;
1333     // call ourself with a rect
1334     // is this OK if paint has a rasterizer?
1335     draw.drawRect(r, paintWithShader);
1336 }
1337 
1338 ///////////////////////////////////////////////////////////////////////////////
1339 
1340 #include "SkPaintPriv.h"
1341 #include "SkScalerContext.h"
1342 #include "SkGlyphCache.h"
1343 #include "SkTextToPathIter.h"
1344 #include "SkUtils.h"
1345 
ShouldDrawTextAsPaths(const SkPaint & paint,const SkMatrix & ctm)1346 bool SkDraw::ShouldDrawTextAsPaths(const SkPaint& paint, const SkMatrix& ctm) {
1347     // hairline glyphs are fast enough so we don't need to cache them
1348     if (SkPaint::kStroke_Style == paint.getStyle() && 0 == paint.getStrokeWidth()) {
1349         return true;
1350     }
1351 
1352     // we don't cache perspective
1353     if (ctm.hasPerspective()) {
1354         return true;
1355     }
1356 
1357     SkMatrix textM;
1358     SkPaintPriv::MakeTextMatrix(&textM, paint);
1359     return SkPaint::TooBigToUseCache(ctm, textM);
1360 }
1361 
drawText_asPaths(const char text[],size_t byteLength,SkScalar x,SkScalar y,const SkPaint & paint) const1362 void SkDraw::drawText_asPaths(const char text[], size_t byteLength, SkScalar x, SkScalar y,
1363                               const SkPaint& paint) const {
1364     SkDEBUGCODE(this->validate();)
1365 
1366     SkTextToPathIter iter(text, byteLength, paint, true);
1367 
1368     SkMatrix    matrix;
1369     matrix.setScale(iter.getPathScale(), iter.getPathScale());
1370     matrix.postTranslate(x, y);
1371 
1372     const SkPath* iterPath;
1373     SkScalar xpos, prevXPos = 0;
1374 
1375     while (iter.next(&iterPath, &xpos)) {
1376         matrix.postTranslate(xpos - prevXPos, 0);
1377         if (iterPath) {
1378             this->drawPath(*iterPath, iter.getPaint(), &matrix, false);
1379         }
1380         prevXPos = xpos;
1381     }
1382 }
1383 
1384 // disable warning : local variable used without having been initialized
1385 #if defined _WIN32
1386 #pragma warning ( push )
1387 #pragma warning ( disable : 4701 )
1388 #endif
1389 
1390 ////////////////////////////////////////////////////////////////////////////////////////////////////
1391 
1392 class DrawOneGlyph {
1393 public:
DrawOneGlyph(const SkDraw & draw,const SkPaint & paint,SkGlyphCache * cache,SkBlitter * blitter)1394     DrawOneGlyph(const SkDraw& draw, const SkPaint& paint, SkGlyphCache* cache, SkBlitter* blitter)
1395         : fUseRegionToDraw(UsingRegionToDraw(draw.fRC))
1396         , fGlyphCache(cache)
1397         , fBlitter(blitter)
1398         , fClip(fUseRegionToDraw ? &draw.fRC->bwRgn() : nullptr)
1399         , fDraw(draw)
1400         , fPaint(paint)
1401         , fClipBounds(PickClipBounds(draw)) { }
1402 
operator ()(const SkGlyph & glyph,SkPoint position,SkPoint rounding)1403     void operator()(const SkGlyph& glyph, SkPoint position, SkPoint rounding) {
1404         position += rounding;
1405         // Prevent glyphs from being drawn outside of or straddling the edge of device space.
1406         // Comparisons written a little weirdly so that NaN coordinates are treated safely.
1407         auto gt = [](float a, int b) { return !(a <= (float)b); };
1408         auto lt = [](float a, int b) { return !(a >= (float)b); };
1409         if (gt(position.fX, INT_MAX - (INT16_MAX + UINT16_MAX)) ||
1410             lt(position.fX, INT_MIN - (INT16_MIN + 0 /*UINT16_MIN*/)) ||
1411             gt(position.fY, INT_MAX - (INT16_MAX + UINT16_MAX)) ||
1412             lt(position.fY, INT_MIN - (INT16_MIN + 0 /*UINT16_MIN*/))) {
1413             return;
1414         }
1415 
1416         int left = SkScalarFloorToInt(position.fX);
1417         int top  = SkScalarFloorToInt(position.fY);
1418         SkASSERT(glyph.fWidth > 0 && glyph.fHeight > 0);
1419 
1420         left += glyph.fLeft;
1421         top  += glyph.fTop;
1422 
1423         int right   = left + glyph.fWidth;
1424         int bottom  = top  + glyph.fHeight;
1425 
1426         SkMask mask;
1427         mask.fBounds.set(left, top, right, bottom);
1428         SkASSERT(!mask.fBounds.isEmpty());
1429 
1430         if (fUseRegionToDraw) {
1431             SkRegion::Cliperator clipper(*fClip, mask.fBounds);
1432 
1433             if (!clipper.done() && this->getImageData(glyph, &mask)) {
1434                 const SkIRect& cr = clipper.rect();
1435                 do {
1436                     this->blitMask(mask, cr);
1437                     clipper.next();
1438                 } while (!clipper.done());
1439             }
1440         } else {
1441             SkIRect  storage;
1442             SkIRect* bounds = &mask.fBounds;
1443 
1444             // this extra test is worth it, assuming that most of the time it succeeds
1445             // since we can avoid writing to storage
1446             if (!fClipBounds.containsNoEmptyCheck(mask.fBounds)) {
1447                 if (!storage.intersectNoEmptyCheck(mask.fBounds, fClipBounds))
1448                     return;
1449                 bounds = &storage;
1450             }
1451 
1452             if (this->getImageData(glyph, &mask)) {
1453                 this->blitMask(mask, *bounds);
1454             }
1455         }
1456     }
1457 
1458 private:
UsingRegionToDraw(const SkRasterClip * rClip)1459     static bool UsingRegionToDraw(const SkRasterClip* rClip) {
1460         return rClip->isBW() && !rClip->isRect();
1461     }
1462 
PickClipBounds(const SkDraw & draw)1463     static SkIRect PickClipBounds(const SkDraw& draw) {
1464         const SkRasterClip& rasterClip = *draw.fRC;
1465 
1466         if (rasterClip.isBW()) {
1467             return rasterClip.bwRgn().getBounds();
1468         } else {
1469             return rasterClip.aaRgn().getBounds();
1470         }
1471     }
1472 
getImageData(const SkGlyph & glyph,SkMask * mask)1473     bool getImageData(const SkGlyph& glyph, SkMask* mask) {
1474         uint8_t* bits = (uint8_t*)(fGlyphCache->findImage(glyph));
1475         if (nullptr == bits) {
1476             return false;  // can't rasterize glyph
1477         }
1478         mask->fImage    = bits;
1479         mask->fRowBytes = glyph.rowBytes();
1480         mask->fFormat   = static_cast<SkMask::Format>(glyph.fMaskFormat);
1481         return true;
1482     }
1483 
blitMask(const SkMask & mask,const SkIRect & clip) const1484     void blitMask(const SkMask& mask, const SkIRect& clip) const {
1485         if (SkMask::kARGB32_Format == mask.fFormat) {
1486             SkBitmap bm;
1487             bm.installPixels(
1488                 SkImageInfo::MakeN32Premul(mask.fBounds.width(), mask.fBounds.height()),
1489                 (SkPMColor*)mask.fImage, mask.fRowBytes);
1490 
1491             fDraw.drawSprite(bm, mask.fBounds.x(), mask.fBounds.y(), fPaint);
1492         } else {
1493             fBlitter->blitMask(mask, clip);
1494         }
1495     }
1496 
1497     const bool            fUseRegionToDraw;
1498     SkGlyphCache  * const fGlyphCache;
1499     SkBlitter     * const fBlitter;
1500     const SkRegion* const fClip;
1501     const SkDraw&         fDraw;
1502     const SkPaint&        fPaint;
1503     const SkIRect         fClipBounds;
1504 };
1505 
1506 ////////////////////////////////////////////////////////////////////////////////////////////////////
1507 
scalerContextFlags() const1508 uint32_t SkDraw::scalerContextFlags() const {
1509     uint32_t flags = SkPaint::kBoostContrast_ScalerContextFlag;
1510     if (!fDst.colorSpace()) {
1511         flags |= SkPaint::kFakeGamma_ScalerContextFlag;
1512     }
1513     return flags;
1514 }
1515 
drawText(const char text[],size_t byteLength,SkScalar x,SkScalar y,const SkPaint & paint,const SkSurfaceProps * props) const1516 void SkDraw::drawText(const char text[], size_t byteLength, SkScalar x, SkScalar y,
1517                       const SkPaint& paint, const SkSurfaceProps* props) const {
1518     SkASSERT(byteLength == 0 || text != nullptr);
1519 
1520     SkDEBUGCODE(this->validate();)
1521 
1522     // nothing to draw
1523     if (text == nullptr || byteLength == 0 || fRC->isEmpty()) {
1524         return;
1525     }
1526 
1527     // SkScalarRec doesn't currently have a way of representing hairline stroke and
1528     // will fill if its frame-width is 0.
1529     if (ShouldDrawTextAsPaths(paint, *fMatrix)) {
1530         this->drawText_asPaths(text, byteLength, x, y, paint);
1531         return;
1532     }
1533 
1534     SkAutoGlyphCache cache(paint, props, this->scalerContextFlags(), fMatrix);
1535 
1536     // The Blitter Choose needs to be live while using the blitter below.
1537     SkAutoBlitterChoose    blitterChooser(fDst, *fMatrix, paint);
1538     SkAAClipBlitterWrapper wrapper(*fRC, blitterChooser.get());
1539     DrawOneGlyph           drawOneGlyph(*this, paint, cache.get(), wrapper.getBlitter());
1540 
1541     SkFindAndPlaceGlyph::ProcessText(
1542         paint.getTextEncoding(), text, byteLength,
1543         {x, y}, *fMatrix, paint.getTextAlign(), cache.get(), drawOneGlyph);
1544 }
1545 
1546 //////////////////////////////////////////////////////////////////////////////
1547 
drawPosText_asPaths(const char text[],size_t byteLength,const SkScalar pos[],int scalarsPerPosition,const SkPoint & offset,const SkPaint & origPaint,const SkSurfaceProps * props) const1548 void SkDraw::drawPosText_asPaths(const char text[], size_t byteLength, const SkScalar pos[],
1549                                  int scalarsPerPosition, const SkPoint& offset,
1550                                  const SkPaint& origPaint, const SkSurfaceProps* props) const {
1551     // setup our std paint, in hopes of getting hits in the cache
1552     SkPaint paint(origPaint);
1553     SkScalar matrixScale = paint.setupForAsPaths();
1554 
1555     SkMatrix matrix;
1556     matrix.setScale(matrixScale, matrixScale);
1557 
1558     // Temporarily jam in kFill, so we only ever ask for the raw outline from the cache.
1559     paint.setStyle(SkPaint::kFill_Style);
1560     paint.setPathEffect(nullptr);
1561 
1562     SkPaint::GlyphCacheProc glyphCacheProc = SkPaint::GetGlyphCacheProc(paint.getTextEncoding(),
1563                                                                         paint.isDevKernText(),
1564                                                                         true);
1565     SkAutoGlyphCache cache(paint, props, this->scalerContextFlags(), nullptr);
1566 
1567     const char*        stop = text + byteLength;
1568     SkTextAlignProc    alignProc(paint.getTextAlign());
1569     SkTextMapStateProc tmsProc(SkMatrix::I(), offset, scalarsPerPosition);
1570 
1571     // Now restore the original settings, so we "draw" with whatever style/stroking.
1572     paint.setStyle(origPaint.getStyle());
1573     paint.setPathEffect(origPaint.refPathEffect());
1574 
1575     while (text < stop) {
1576         const SkGlyph& glyph = glyphCacheProc(cache.get(), &text);
1577         if (glyph.fWidth) {
1578             const SkPath* path = cache->findPath(glyph);
1579             if (path) {
1580                 SkPoint tmsLoc;
1581                 tmsProc(pos, &tmsLoc);
1582                 SkPoint loc;
1583                 alignProc(tmsLoc, glyph, &loc);
1584 
1585                 matrix[SkMatrix::kMTransX] = loc.fX;
1586                 matrix[SkMatrix::kMTransY] = loc.fY;
1587                 this->drawPath(*path, paint, &matrix, false);
1588             }
1589         }
1590         pos += scalarsPerPosition;
1591     }
1592 }
1593 
drawPosText(const char text[],size_t byteLength,const SkScalar pos[],int scalarsPerPosition,const SkPoint & offset,const SkPaint & paint,const SkSurfaceProps * props) const1594 void SkDraw::drawPosText(const char text[], size_t byteLength, const SkScalar pos[],
1595                          int scalarsPerPosition, const SkPoint& offset, const SkPaint& paint,
1596                          const SkSurfaceProps* props) const {
1597     SkASSERT(byteLength == 0 || text != nullptr);
1598     SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
1599 
1600     SkDEBUGCODE(this->validate();)
1601 
1602     // nothing to draw
1603     if (text == nullptr || byteLength == 0 || fRC->isEmpty()) {
1604         return;
1605     }
1606 
1607     if (ShouldDrawTextAsPaths(paint, *fMatrix)) {
1608         this->drawPosText_asPaths(text, byteLength, pos, scalarsPerPosition, offset, paint, props);
1609         return;
1610     }
1611 
1612     SkAutoGlyphCache cache(paint, props, this->scalerContextFlags(), fMatrix);
1613 
1614     // The Blitter Choose needs to be live while using the blitter below.
1615     SkAutoBlitterChoose    blitterChooser(fDst, *fMatrix, paint);
1616     SkAAClipBlitterWrapper wrapper(*fRC, blitterChooser.get());
1617     DrawOneGlyph           drawOneGlyph(*this, paint, cache.get(), wrapper.getBlitter());
1618     SkPaint::Align         textAlignment = paint.getTextAlign();
1619 
1620     SkFindAndPlaceGlyph::ProcessPosText(
1621         paint.getTextEncoding(), text, byteLength,
1622         offset, *fMatrix, pos, scalarsPerPosition, textAlignment, cache.get(), drawOneGlyph);
1623 }
1624 
1625 #if defined _WIN32
1626 #pragma warning ( pop )
1627 #endif
1628 
1629 ////////////////////////////////////////////////////////////////////////////////////////////////
1630 
1631 #ifdef SK_DEBUG
1632 
validate() const1633 void SkDraw::validate() const {
1634     SkASSERT(fMatrix != nullptr);
1635     SkASSERT(fRC != nullptr);
1636 
1637     const SkIRect&  cr = fRC->getBounds();
1638     SkIRect         br;
1639 
1640     br.set(0, 0, fDst.width(), fDst.height());
1641     SkASSERT(cr.isEmpty() || br.contains(cr));
1642 }
1643 
1644 #endif
1645 
1646 ////////////////////////////////////////////////////////////////////////////////////////////////
1647 
1648 #include "SkPath.h"
1649 #include "SkDraw.h"
1650 #include "SkRegion.h"
1651 #include "SkBlitter.h"
1652 
compute_bounds(const SkPath & devPath,const SkIRect * clipBounds,const SkMaskFilter * filter,const SkMatrix * filterMatrix,SkIRect * bounds)1653 static bool compute_bounds(const SkPath& devPath, const SkIRect* clipBounds,
1654                            const SkMaskFilter* filter, const SkMatrix* filterMatrix,
1655                            SkIRect* bounds) {
1656     if (devPath.isEmpty()) {
1657         return false;
1658     }
1659 
1660     //  init our bounds from the path
1661     *bounds = devPath.getBounds().makeOutset(SK_ScalarHalf, SK_ScalarHalf).roundOut();
1662 
1663     SkIPoint margin = SkIPoint::Make(0, 0);
1664     if (filter) {
1665         SkASSERT(filterMatrix);
1666 
1667         SkMask srcM, dstM;
1668 
1669         srcM.fBounds = *bounds;
1670         srcM.fFormat = SkMask::kA8_Format;
1671         if (!filter->filterMask(&dstM, srcM, *filterMatrix, &margin)) {
1672             return false;
1673         }
1674     }
1675 
1676     // (possibly) trim the bounds to reflect the clip
1677     // (plus whatever slop the filter needs)
1678     if (clipBounds) {
1679         // Ugh. Guard against gigantic margins from wacky filters. Without this
1680         // check we can request arbitrary amounts of slop beyond our visible
1681         // clip, and bring down the renderer (at least on finite RAM machines
1682         // like handsets, etc.). Need to balance this invented value between
1683         // quality of large filters like blurs, and the corresponding memory
1684         // requests.
1685         static const int MAX_MARGIN = 128;
1686         if (!bounds->intersect(clipBounds->makeOutset(SkMin32(margin.fX, MAX_MARGIN),
1687                                                       SkMin32(margin.fY, MAX_MARGIN)))) {
1688             return false;
1689         }
1690     }
1691 
1692     return true;
1693 }
1694 
draw_into_mask(const SkMask & mask,const SkPath & devPath,SkStrokeRec::InitStyle style)1695 static void draw_into_mask(const SkMask& mask, const SkPath& devPath,
1696                            SkStrokeRec::InitStyle style) {
1697     SkDraw draw;
1698     if (!draw.fDst.reset(mask)) {
1699         return;
1700     }
1701 
1702     SkRasterClip    clip;
1703     SkMatrix        matrix;
1704     SkPaint         paint;
1705 
1706     clip.setRect(SkIRect::MakeWH(mask.fBounds.width(), mask.fBounds.height()));
1707     matrix.setTranslate(-SkIntToScalar(mask.fBounds.fLeft),
1708                         -SkIntToScalar(mask.fBounds.fTop));
1709 
1710     draw.fRC        = &clip;
1711     draw.fMatrix    = &matrix;
1712     paint.setAntiAlias(true);
1713     switch (style) {
1714         case SkStrokeRec::kHairline_InitStyle:
1715             SkASSERT(!paint.getStrokeWidth());
1716             paint.setStyle(SkPaint::kStroke_Style);
1717             break;
1718         case SkStrokeRec::kFill_InitStyle:
1719             SkASSERT(paint.getStyle() == SkPaint::kFill_Style);
1720             break;
1721 
1722     }
1723     draw.drawPath(devPath, paint);
1724 }
1725 
DrawToMask(const SkPath & devPath,const SkIRect * clipBounds,const SkMaskFilter * filter,const SkMatrix * filterMatrix,SkMask * mask,SkMask::CreateMode mode,SkStrokeRec::InitStyle style)1726 bool SkDraw::DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
1727                         const SkMaskFilter* filter, const SkMatrix* filterMatrix,
1728                         SkMask* mask, SkMask::CreateMode mode,
1729                         SkStrokeRec::InitStyle style) {
1730     if (SkMask::kJustRenderImage_CreateMode != mode) {
1731         if (!compute_bounds(devPath, clipBounds, filter, filterMatrix, &mask->fBounds))
1732             return false;
1733     }
1734 
1735     if (SkMask::kComputeBoundsAndRenderImage_CreateMode == mode) {
1736         mask->fFormat = SkMask::kA8_Format;
1737         mask->fRowBytes = mask->fBounds.width();
1738         size_t size = mask->computeImageSize();
1739         if (0 == size) {
1740             // we're too big to allocate the mask, abort
1741             return false;
1742         }
1743         mask->fImage = SkMask::AllocImage(size);
1744         memset(mask->fImage, 0, mask->computeImageSize());
1745     }
1746 
1747     if (SkMask::kJustComputeBounds_CreateMode != mode) {
1748         draw_into_mask(*mask, devPath, style);
1749     }
1750 
1751     return true;
1752 }
1753