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