SkiaCanvas.cpp revision 876d56612ab8ec7032f702905d694670e6c4febd
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "Canvas.h"
18
19#include <SkCanvas.h>
20#include <SkClipStack.h>
21#include <SkDevice.h>
22#include <SkDeque.h>
23#include <SkDrawFilter.h>
24#include <SkGraphics.h>
25#include <SkShader.h>
26#include <SkTArray.h>
27#include <SkTemplates.h>
28
29namespace android {
30
31// Holds an SkCanvas reference plus additional native data.
32class SkiaCanvas : public Canvas {
33public:
34    explicit SkiaCanvas(const SkBitmap& bitmap);
35
36    /**
37     *  Create a new SkiaCanvas.
38     *
39     *  @param canvas SkCanvas to handle calls made to this SkiaCanvas. Must
40     *      not be NULL. This constructor will ref() the SkCanvas, and unref()
41     *      it in its destructor.
42     */
43    explicit SkiaCanvas(SkCanvas* canvas) : mCanvas(canvas) {
44        SkASSERT(canvas);
45        canvas->ref();
46    }
47
48    virtual SkCanvas* asSkCanvas() override {
49        return mCanvas.get();
50    }
51
52    virtual void setBitmap(const SkBitmap& bitmap) override;
53
54    virtual bool isOpaque() override;
55    virtual int width() override;
56    virtual int height() override;
57
58    virtual void setHighContrastText(bool highContrastText) override {}
59    virtual bool isHighContrastText() override { return false; }
60
61    virtual int getSaveCount() const override;
62    virtual int save(SkCanvas::SaveFlags flags) override;
63    virtual void restore() override;
64    virtual void restoreToCount(int saveCount) override;
65
66    virtual int saveLayer(float left, float top, float right, float bottom,
67                const SkPaint* paint, SkCanvas::SaveFlags flags) override;
68    virtual int saveLayerAlpha(float left, float top, float right, float bottom,
69            int alpha, SkCanvas::SaveFlags flags) override;
70
71    virtual void getMatrix(SkMatrix* outMatrix) const override;
72    virtual void setMatrix(const SkMatrix& matrix) override;
73    virtual void setLocalMatrix(const SkMatrix& matrix) override { this->setMatrix(matrix); }
74    virtual void concat(const SkMatrix& matrix) override;
75    virtual void rotate(float degrees) override;
76    virtual void scale(float sx, float sy) override;
77    virtual void skew(float sx, float sy) override;
78    virtual void translate(float dx, float dy) override;
79
80    virtual bool getClipBounds(SkRect* outRect) const override;
81    virtual bool quickRejectRect(float left, float top, float right, float bottom) const override;
82    virtual bool quickRejectPath(const SkPath& path) const override;
83    virtual bool clipRect(float left, float top, float right, float bottom,
84            SkRegion::Op op) override;
85    virtual bool clipPath(const SkPath* path, SkRegion::Op op) override;
86    virtual bool clipRegion(const SkRegion* region, SkRegion::Op op) override;
87
88    virtual SkDrawFilter* getDrawFilter() override;
89    virtual void setDrawFilter(SkDrawFilter* drawFilter) override;
90
91    virtual void drawColor(int color, SkXfermode::Mode mode) override;
92    virtual void drawPaint(const SkPaint& paint) override;
93
94    virtual void drawPoint(float x, float y, const SkPaint& paint) override;
95    virtual void drawPoints(const float* points, int count, const SkPaint& paint) override;
96    virtual void drawLine(float startX, float startY, float stopX, float stopY,
97            const SkPaint& paint) override;
98    virtual void drawLines(const float* points, int count, const SkPaint& paint) override;
99    virtual void drawRect(float left, float top, float right, float bottom,
100            const SkPaint& paint) override;
101    virtual void drawRegion(const SkRegion& region, const SkPaint& paint) override;
102    virtual void drawRoundRect(float left, float top, float right, float bottom,
103            float rx, float ry, const SkPaint& paint) override;
104    virtual void drawCircle(float x, float y, float radius, const SkPaint& paint) override;
105    virtual void drawOval(float left, float top, float right, float bottom,
106            const SkPaint& paint) override;
107    virtual void drawArc(float left, float top, float right, float bottom,
108            float startAngle, float sweepAngle, bool useCenter, const SkPaint& paint) override;
109    virtual void drawPath(const SkPath& path, const SkPaint& paint) override;
110    virtual void drawVertices(SkCanvas::VertexMode vertexMode, int vertexCount,
111            const float* verts, const float* tex, const int* colors,
112            const uint16_t* indices, int indexCount, const SkPaint& paint) override;
113
114    virtual void drawBitmap(const SkBitmap& bitmap, float left, float top,
115            const SkPaint* paint) override;
116    virtual void drawBitmap(const SkBitmap& bitmap, const SkMatrix& matrix,
117            const SkPaint* paint) override;
118    virtual void drawBitmap(const SkBitmap& bitmap, float srcLeft, float srcTop,
119            float srcRight, float srcBottom, float dstLeft, float dstTop,
120            float dstRight, float dstBottom, const SkPaint* paint) override;
121    virtual void drawBitmapMesh(const SkBitmap& bitmap, int meshWidth, int meshHeight,
122            const float* vertices, const int* colors, const SkPaint* paint) override;
123
124    virtual void drawText(const uint16_t* text, const float* positions, int count,
125            const SkPaint& paint, float x, float y,
126            float boundsLeft, float boundsTop, float boundsRight, float boundsBottom,
127            float totalAdvance) override;
128    virtual void drawPosText(const uint16_t* text, const float* positions, int count,
129            int posCount, const SkPaint& paint) override;
130    virtual void drawTextOnPath(const uint16_t* glyphs, int count, const SkPath& path,
131            float hOffset, float vOffset, const SkPaint& paint) override;
132
133    virtual bool drawTextAbsolutePos() const  override { return true; }
134
135private:
136    struct SaveRec {
137        int                 saveCount;
138        SkCanvas::SaveFlags saveFlags;
139    };
140
141    void recordPartialSave(SkCanvas::SaveFlags flags);
142    void saveClipsForFrame(SkTArray<SkClipStack::Element>& clips, int frameSaveCount);
143    void applyClips(const SkTArray<SkClipStack::Element>& clips);
144
145    void drawPoints(const float* points, int count, const SkPaint& paint,
146                    SkCanvas::PointMode mode);
147    void drawTextDecorations(float x, float y, float length, const SkPaint& paint);
148
149    SkAutoTUnref<SkCanvas> mCanvas;
150    SkAutoTDelete<SkDeque> mSaveStack; // lazily allocated, tracks partial saves.
151};
152
153Canvas* Canvas::create_canvas(const SkBitmap& bitmap) {
154    return new SkiaCanvas(bitmap);
155}
156
157Canvas* Canvas::create_canvas(SkCanvas* skiaCanvas) {
158    return new SkiaCanvas(skiaCanvas);
159}
160
161SkiaCanvas::SkiaCanvas(const SkBitmap& bitmap) {
162    mCanvas.reset(new SkCanvas(bitmap));
163}
164
165// ----------------------------------------------------------------------------
166// Canvas state operations: Replace Bitmap
167// ----------------------------------------------------------------------------
168
169class ClipCopier : public SkCanvas::ClipVisitor {
170public:
171    ClipCopier(SkCanvas* dstCanvas) : m_dstCanvas(dstCanvas) {}
172
173    virtual void clipRect(const SkRect& rect, SkRegion::Op op, bool antialias) {
174        m_dstCanvas->clipRect(rect, op, antialias);
175    }
176    virtual void clipRRect(const SkRRect& rrect, SkRegion::Op op, bool antialias) {
177        m_dstCanvas->clipRRect(rrect, op, antialias);
178    }
179    virtual void clipPath(const SkPath& path, SkRegion::Op op, bool antialias) {
180        m_dstCanvas->clipPath(path, op, antialias);
181    }
182
183private:
184    SkCanvas* m_dstCanvas;
185};
186
187void SkiaCanvas::setBitmap(const SkBitmap& bitmap) {
188    SkCanvas* newCanvas = new SkCanvas(bitmap);
189    SkASSERT(newCanvas);
190
191    if (!bitmap.isNull()) {
192        // Copy the canvas matrix & clip state.
193        newCanvas->setMatrix(mCanvas->getTotalMatrix());
194        if (NULL != mCanvas->getDevice() && NULL != newCanvas->getDevice()) {
195            ClipCopier copier(newCanvas);
196            mCanvas->replayClips(&copier);
197        }
198    }
199
200    // unrefs the existing canvas
201    mCanvas.reset(newCanvas);
202
203    // clean up the old save stack
204    mSaveStack.reset(NULL);
205}
206
207// ----------------------------------------------------------------------------
208// Canvas state operations
209// ----------------------------------------------------------------------------
210
211bool SkiaCanvas::isOpaque() {
212    return mCanvas->getDevice()->accessBitmap(false).isOpaque();
213}
214
215int SkiaCanvas::width() {
216    return mCanvas->getBaseLayerSize().width();
217}
218
219int SkiaCanvas::height() {
220    return mCanvas->getBaseLayerSize().height();
221}
222
223// ----------------------------------------------------------------------------
224// Canvas state operations: Save (layer)
225// ----------------------------------------------------------------------------
226
227int SkiaCanvas::getSaveCount() const {
228    return mCanvas->getSaveCount();
229}
230
231int SkiaCanvas::save(SkCanvas::SaveFlags flags) {
232    int count = mCanvas->save();
233    recordPartialSave(flags);
234    return count;
235}
236
237void SkiaCanvas::restore() {
238    const SaveRec* rec = (NULL == mSaveStack.get())
239            ? NULL
240            : static_cast<SaveRec*>(mSaveStack->back());
241    int currentSaveCount = mCanvas->getSaveCount() - 1;
242    SkASSERT(NULL == rec || currentSaveCount >= rec->saveCount);
243
244    if (NULL == rec || rec->saveCount != currentSaveCount) {
245        // Fast path - no record for this frame.
246        mCanvas->restore();
247        return;
248    }
249
250    bool preserveMatrix = !(rec->saveFlags & SkCanvas::kMatrix_SaveFlag);
251    bool preserveClip   = !(rec->saveFlags & SkCanvas::kClip_SaveFlag);
252
253    SkMatrix savedMatrix;
254    if (preserveMatrix) {
255        savedMatrix = mCanvas->getTotalMatrix();
256    }
257
258    SkTArray<SkClipStack::Element> savedClips;
259    if (preserveClip) {
260        saveClipsForFrame(savedClips, currentSaveCount);
261    }
262
263    mCanvas->restore();
264
265    if (preserveMatrix) {
266        mCanvas->setMatrix(savedMatrix);
267    }
268
269    if (preserveClip && !savedClips.empty()) {
270        applyClips(savedClips);
271    }
272
273    mSaveStack->pop_back();
274}
275
276void SkiaCanvas::restoreToCount(int restoreCount) {
277    while (mCanvas->getSaveCount() > restoreCount) {
278        this->restore();
279    }
280}
281
282int SkiaCanvas::saveLayer(float left, float top, float right, float bottom,
283            const SkPaint* paint, SkCanvas::SaveFlags flags) {
284    SkRect bounds = SkRect::MakeLTRB(left, top, right, bottom);
285    int count = mCanvas->saveLayer(&bounds, paint, flags | SkCanvas::kMatrixClip_SaveFlag);
286    recordPartialSave(flags);
287    return count;
288}
289
290int SkiaCanvas::saveLayerAlpha(float left, float top, float right, float bottom,
291        int alpha, SkCanvas::SaveFlags flags) {
292    SkRect bounds = SkRect::MakeLTRB(left, top, right, bottom);
293    int count = mCanvas->saveLayerAlpha(&bounds, alpha, flags | SkCanvas::kMatrixClip_SaveFlag);
294    recordPartialSave(flags);
295    return count;
296}
297
298// ----------------------------------------------------------------------------
299// functions to emulate legacy SaveFlags (i.e. independent matrix/clip flags)
300// ----------------------------------------------------------------------------
301
302void SkiaCanvas::recordPartialSave(SkCanvas::SaveFlags flags) {
303    // A partial save is a save operation which doesn't capture the full canvas state.
304    // (either kMatrix_SaveFlags or kClip_SaveFlag is missing).
305
306    // Mask-out non canvas state bits.
307    flags = static_cast<SkCanvas::SaveFlags>(flags & SkCanvas::kMatrixClip_SaveFlag);
308
309    if (SkCanvas::kMatrixClip_SaveFlag == flags) {
310        // not a partial save.
311        return;
312    }
313
314    if (NULL == mSaveStack.get()) {
315        mSaveStack.reset(SkNEW_ARGS(SkDeque, (sizeof(struct SaveRec), 8)));
316    }
317
318    SaveRec* rec = static_cast<SaveRec*>(mSaveStack->push_back());
319    // Store the save counter in the SkClipStack domain.
320    // (0-based, equal to the number of save ops on the stack).
321    rec->saveCount = mCanvas->getSaveCount() - 1;
322    rec->saveFlags = flags;
323}
324
325void SkiaCanvas::saveClipsForFrame(SkTArray<SkClipStack::Element>& clips, int frameSaveCount) {
326    SkClipStack::Iter clipIterator(*mCanvas->getClipStack(),
327                                   SkClipStack::Iter::kTop_IterStart);
328    while (const SkClipStack::Element* elem = clipIterator.next()) {
329        if (elem->getSaveCount() < frameSaveCount) {
330            // done with the current frame.
331            break;
332        }
333        SkASSERT(elem->getSaveCount() == frameSaveCount);
334        clips.push_back(*elem);
335    }
336}
337
338void SkiaCanvas::applyClips(const SkTArray<SkClipStack::Element>& clips) {
339    ClipCopier clipCopier(mCanvas);
340
341    // The clip stack stores clips in device space.
342    SkMatrix origMatrix = mCanvas->getTotalMatrix();
343    mCanvas->resetMatrix();
344
345    // We pushed the clips in reverse order.
346    for (int i = clips.count() - 1; i >= 0; --i) {
347        clips[i].replay(&clipCopier);
348    }
349
350    mCanvas->setMatrix(origMatrix);
351}
352
353// ----------------------------------------------------------------------------
354// Canvas state operations: Matrix
355// ----------------------------------------------------------------------------
356
357void SkiaCanvas::getMatrix(SkMatrix* outMatrix) const {
358    *outMatrix = mCanvas->getTotalMatrix();
359}
360
361void SkiaCanvas::setMatrix(const SkMatrix& matrix) {
362    mCanvas->setMatrix(matrix);
363}
364
365void SkiaCanvas::concat(const SkMatrix& matrix) {
366    mCanvas->concat(matrix);
367}
368
369void SkiaCanvas::rotate(float degrees) {
370    mCanvas->rotate(degrees);
371}
372
373void SkiaCanvas::scale(float sx, float sy) {
374    mCanvas->scale(sx, sy);
375}
376
377void SkiaCanvas::skew(float sx, float sy) {
378    mCanvas->skew(sx, sy);
379}
380
381void SkiaCanvas::translate(float dx, float dy) {
382    mCanvas->translate(dx, dy);
383}
384
385// ----------------------------------------------------------------------------
386// Canvas state operations: Clips
387// ----------------------------------------------------------------------------
388
389// This function is a mirror of SkCanvas::getClipBounds except that it does
390// not outset the edge of the clip to account for anti-aliasing. There is
391// a skia bug to investigate pushing this logic into back into skia.
392// (see https://code.google.com/p/skia/issues/detail?id=1303)
393bool SkiaCanvas::getClipBounds(SkRect* outRect) const {
394    SkIRect ibounds;
395    if (!mCanvas->getClipDeviceBounds(&ibounds)) {
396        return false;
397    }
398
399    SkMatrix inverse;
400    // if we can't invert the CTM, we can't return local clip bounds
401    if (!mCanvas->getTotalMatrix().invert(&inverse)) {
402        if (outRect) {
403            outRect->setEmpty();
404        }
405        return false;
406    }
407
408    if (NULL != outRect) {
409        SkRect r = SkRect::Make(ibounds);
410        inverse.mapRect(outRect, r);
411    }
412    return true;
413}
414
415bool SkiaCanvas::quickRejectRect(float left, float top, float right, float bottom) const {
416    SkRect bounds = SkRect::MakeLTRB(left, top, right, bottom);
417    return mCanvas->quickReject(bounds);
418}
419
420bool SkiaCanvas::quickRejectPath(const SkPath& path) const {
421    return mCanvas->quickReject(path);
422}
423
424bool SkiaCanvas::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
425    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
426    mCanvas->clipRect(rect, op);
427    return !mCanvas->isClipEmpty();
428}
429
430bool SkiaCanvas::clipPath(const SkPath* path, SkRegion::Op op) {
431    mCanvas->clipPath(*path, op);
432    return !mCanvas->isClipEmpty();
433}
434
435bool SkiaCanvas::clipRegion(const SkRegion* region, SkRegion::Op op) {
436    SkPath rgnPath;
437    if (region->getBoundaryPath(&rgnPath)) {
438        // The region is specified in device space.
439        SkMatrix savedMatrix = mCanvas->getTotalMatrix();
440        mCanvas->resetMatrix();
441        mCanvas->clipPath(rgnPath, op);
442        mCanvas->setMatrix(savedMatrix);
443    } else {
444        mCanvas->clipRect(SkRect::MakeEmpty(), op);
445    }
446    return !mCanvas->isClipEmpty();
447}
448
449// ----------------------------------------------------------------------------
450// Canvas state operations: Filters
451// ----------------------------------------------------------------------------
452
453SkDrawFilter* SkiaCanvas::getDrawFilter() {
454    return mCanvas->getDrawFilter();
455}
456
457void SkiaCanvas::setDrawFilter(SkDrawFilter* drawFilter) {
458    mCanvas->setDrawFilter(drawFilter);
459}
460
461// ----------------------------------------------------------------------------
462// Canvas draw operations
463// ----------------------------------------------------------------------------
464
465void SkiaCanvas::drawColor(int color, SkXfermode::Mode mode) {
466    mCanvas->drawColor(color, mode);
467}
468
469void SkiaCanvas::drawPaint(const SkPaint& paint) {
470    mCanvas->drawPaint(paint);
471}
472
473// ----------------------------------------------------------------------------
474// Canvas draw operations: Geometry
475// ----------------------------------------------------------------------------
476
477void SkiaCanvas::drawPoints(const float* points, int count, const SkPaint& paint,
478                            SkCanvas::PointMode mode) {
479    // convert the floats into SkPoints
480    count >>= 1;    // now it is the number of points
481    SkAutoSTMalloc<32, SkPoint> storage(count);
482    SkPoint* pts = storage.get();
483    for (int i = 0; i < count; i++) {
484        pts[i].set(points[0], points[1]);
485        points += 2;
486    }
487    mCanvas->drawPoints(mode, count, pts, paint);
488}
489
490
491void SkiaCanvas::drawPoint(float x, float y, const SkPaint& paint) {
492    mCanvas->drawPoint(x, y, paint);
493}
494
495void SkiaCanvas::drawPoints(const float* points, int count, const SkPaint& paint) {
496    this->drawPoints(points, count, paint, SkCanvas::kPoints_PointMode);
497}
498
499void SkiaCanvas::drawLine(float startX, float startY, float stopX, float stopY,
500                          const SkPaint& paint) {
501    mCanvas->drawLine(startX, startY, stopX, stopY, paint);
502}
503
504void SkiaCanvas::drawLines(const float* points, int count, const SkPaint& paint) {
505    this->drawPoints(points, count, paint, SkCanvas::kLines_PointMode);
506}
507
508void SkiaCanvas::drawRect(float left, float top, float right, float bottom,
509        const SkPaint& paint) {
510    mCanvas->drawRectCoords(left, top, right, bottom, paint);
511
512}
513
514void SkiaCanvas::drawRegion(const SkRegion& region, const SkPaint& paint) {
515    SkRegion::Iterator it(region);
516    while (!it.done()) {
517        mCanvas->drawRect(SkRect::Make(it.rect()), paint);
518        it.next();
519    }
520}
521
522void SkiaCanvas::drawRoundRect(float left, float top, float right, float bottom,
523        float rx, float ry, const SkPaint& paint) {
524    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
525    mCanvas->drawRoundRect(rect, rx, ry, paint);
526}
527
528void SkiaCanvas::drawCircle(float x, float y, float radius, const SkPaint& paint) {
529    mCanvas->drawCircle(x, y, radius, paint);
530}
531
532void SkiaCanvas::drawOval(float left, float top, float right, float bottom, const SkPaint& paint) {
533    SkRect oval = SkRect::MakeLTRB(left, top, right, bottom);
534    mCanvas->drawOval(oval, paint);
535}
536
537void SkiaCanvas::drawArc(float left, float top, float right, float bottom,
538        float startAngle, float sweepAngle, bool useCenter, const SkPaint& paint) {
539    SkRect arc = SkRect::MakeLTRB(left, top, right, bottom);
540    mCanvas->drawArc(arc, startAngle, sweepAngle, useCenter, paint);
541}
542
543void SkiaCanvas::drawPath(const SkPath& path, const SkPaint& paint) {
544    mCanvas->drawPath(path, paint);
545}
546
547void SkiaCanvas::drawVertices(SkCanvas::VertexMode vertexMode, int vertexCount,
548                              const float* verts, const float* texs, const int* colors,
549                              const uint16_t* indices, int indexCount, const SkPaint& paint) {
550#ifndef SK_SCALAR_IS_FLOAT
551    SkDEBUGFAIL("SkScalar must be a float for these conversions to be valid");
552#endif
553    const int ptCount = vertexCount >> 1;
554    mCanvas->drawVertices(vertexMode, ptCount, (SkPoint*)verts, (SkPoint*)texs,
555                          (SkColor*)colors, NULL, indices, indexCount, paint);
556}
557
558// ----------------------------------------------------------------------------
559// Canvas draw operations: Bitmaps
560// ----------------------------------------------------------------------------
561
562void SkiaCanvas::drawBitmap(const SkBitmap& bitmap, float left, float top, const SkPaint* paint) {
563    mCanvas->drawBitmap(bitmap, left, top, paint);
564}
565
566void SkiaCanvas::drawBitmap(const SkBitmap& bitmap, const SkMatrix& matrix, const SkPaint* paint) {
567    SkAutoCanvasRestore acr(mCanvas, true);
568    mCanvas->concat(matrix);
569    mCanvas->drawBitmap(bitmap, 0, 0, paint);
570}
571
572void SkiaCanvas::drawBitmap(const SkBitmap& bitmap, float srcLeft, float srcTop,
573                            float srcRight, float srcBottom, float dstLeft, float dstTop,
574                            float dstRight, float dstBottom, const SkPaint* paint) {
575    SkRect srcRect = SkRect::MakeLTRB(srcLeft, srcTop, srcRight, srcBottom);
576    SkRect dstRect = SkRect::MakeLTRB(dstLeft, dstTop, dstRight, dstBottom);
577    mCanvas->drawBitmapRectToRect(bitmap, &srcRect, dstRect, paint);
578}
579
580void SkiaCanvas::drawBitmapMesh(const SkBitmap& bitmap, int meshWidth, int meshHeight,
581        const float* vertices, const int* colors, const SkPaint* paint) {
582
583    const int ptCount = (meshWidth + 1) * (meshHeight + 1);
584    const int indexCount = meshWidth * meshHeight * 6;
585
586    /*  Our temp storage holds 2 or 3 arrays.
587        texture points [ptCount * sizeof(SkPoint)]
588        optionally vertex points [ptCount * sizeof(SkPoint)] if we need a
589            copy to convert from float to fixed
590        indices [ptCount * sizeof(uint16_t)]
591    */
592    ssize_t storageSize = ptCount * sizeof(SkPoint); // texs[]
593    storageSize += indexCount * sizeof(uint16_t);  // indices[]
594
595
596#ifndef SK_SCALAR_IS_FLOAT
597    SkDEBUGFAIL("SkScalar must be a float for these conversions to be valid");
598#endif
599    SkAutoMalloc storage(storageSize);
600    SkPoint* texs = (SkPoint*)storage.get();
601    uint16_t* indices = (uint16_t*)(texs + ptCount);
602
603    // cons up texture coordinates and indices
604    {
605        const SkScalar w = SkIntToScalar(bitmap.width());
606        const SkScalar h = SkIntToScalar(bitmap.height());
607        const SkScalar dx = w / meshWidth;
608        const SkScalar dy = h / meshHeight;
609
610        SkPoint* texsPtr = texs;
611        SkScalar y = 0;
612        for (int i = 0; i <= meshHeight; i++) {
613            if (i == meshHeight) {
614                y = h;  // to ensure numerically we hit h exactly
615            }
616            SkScalar x = 0;
617            for (int j = 0; j < meshWidth; j++) {
618                texsPtr->set(x, y);
619                texsPtr += 1;
620                x += dx;
621            }
622            texsPtr->set(w, y);
623            texsPtr += 1;
624            y += dy;
625        }
626        SkASSERT(texsPtr - texs == ptCount);
627    }
628
629    // cons up indices
630    {
631        uint16_t* indexPtr = indices;
632        int index = 0;
633        for (int i = 0; i < meshHeight; i++) {
634            for (int j = 0; j < meshWidth; j++) {
635                // lower-left triangle
636                *indexPtr++ = index;
637                *indexPtr++ = index + meshWidth + 1;
638                *indexPtr++ = index + meshWidth + 2;
639                // upper-right triangle
640                *indexPtr++ = index;
641                *indexPtr++ = index + meshWidth + 2;
642                *indexPtr++ = index + 1;
643                // bump to the next cell
644                index += 1;
645            }
646            // bump to the next row
647            index += 1;
648        }
649        SkASSERT(indexPtr - indices == indexCount);
650        SkASSERT((char*)indexPtr - (char*)storage.get() == storageSize);
651    }
652
653    // double-check that we have legal indices
654#ifdef SK_DEBUG
655    {
656        for (int i = 0; i < indexCount; i++) {
657            SkASSERT((unsigned)indices[i] < (unsigned)ptCount);
658        }
659    }
660#endif
661
662    // cons-up a shader for the bitmap
663    SkPaint tmpPaint;
664    if (paint) {
665        tmpPaint = *paint;
666    }
667    SkShader* shader = SkShader::CreateBitmapShader(bitmap,
668                                                    SkShader::kClamp_TileMode,
669                                                    SkShader::kClamp_TileMode);
670    SkSafeUnref(tmpPaint.setShader(shader));
671
672    mCanvas->drawVertices(SkCanvas::kTriangles_VertexMode, ptCount, (SkPoint*)vertices,
673                         texs, (const SkColor*)colors, NULL, indices,
674                         indexCount, tmpPaint);
675}
676
677// ----------------------------------------------------------------------------
678// Canvas draw operations: Text
679// ----------------------------------------------------------------------------
680
681void SkiaCanvas::drawText(const uint16_t* text, const float* positions, int count,
682        const SkPaint& paint, float x, float y,
683        float boundsLeft, float boundsTop, float boundsRight, float boundsBottom,
684        float totalAdvance) {
685    // Set align to left for drawing, as we don't want individual
686    // glyphs centered or right-aligned; the offset above takes
687    // care of all alignment.
688    SkPaint paintCopy(paint);
689    paintCopy.setTextAlign(SkPaint::kLeft_Align);
690
691    SK_COMPILE_ASSERT(sizeof(SkPoint) == sizeof(float)*2, SkPoint_is_no_longer_2_floats);
692    mCanvas->drawPosText(text, count << 1, reinterpret_cast<const SkPoint*>(positions), paintCopy);
693}
694
695void SkiaCanvas::drawPosText(const uint16_t* text, const float* positions, int count, int posCount,
696        const SkPaint& paint) {
697    SkPoint* posPtr = posCount > 0 ? new SkPoint[posCount] : NULL;
698    int indx;
699    for (indx = 0; indx < posCount; indx++) {
700        posPtr[indx].fX = positions[indx << 1];
701        posPtr[indx].fY = positions[(indx << 1) + 1];
702    }
703
704    SkPaint paintCopy(paint);
705    paintCopy.setTextEncoding(SkPaint::kUTF16_TextEncoding);
706    mCanvas->drawPosText(text, count, posPtr, paintCopy);
707
708    delete[] posPtr;
709}
710
711void SkiaCanvas::drawTextOnPath(const uint16_t* glyphs, int count, const SkPath& path,
712        float hOffset, float vOffset, const SkPaint& paint) {
713    mCanvas->drawTextOnPathHV(glyphs, count << 1, path, hOffset, vOffset, paint);
714}
715
716} // namespace android
717