SkiaCanvas.cpp revision aed7f58fb05a25ce2112829e77c0eb5dd268e8a7
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 "SkiaCanvas.h"
18
19#include "CanvasProperty.h"
20#include "VectorDrawable.h"
21#include "hwui/Bitmap.h"
22#include "hwui/MinikinUtils.h"
23
24#include <SkDrawable.h>
25#include <SkDevice.h>
26#include <SkDeque.h>
27#include <SkDrawFilter.h>
28#include <SkGraphics.h>
29#include <SkImage.h>
30#include <SkImagePriv.h>
31#include <SkRSXform.h>
32#include <SkShader.h>
33#include <SkTemplates.h>
34
35#include <memory>
36
37namespace android {
38
39Canvas* Canvas::create_canvas(const SkBitmap& bitmap) {
40    return new SkiaCanvas(bitmap);
41}
42
43Canvas* Canvas::create_canvas(SkCanvas* skiaCanvas) {
44    return new SkiaCanvas(skiaCanvas);
45}
46
47SkiaCanvas::SkiaCanvas(const SkBitmap& bitmap) {
48    mCanvas.reset(new SkCanvas(bitmap));
49}
50
51void SkiaCanvas::reset(SkCanvas* skiaCanvas) {
52    mCanvas.reset(SkRef(skiaCanvas));
53    mSaveStack.reset(nullptr);
54    mHighContrastText = false;
55}
56
57// ----------------------------------------------------------------------------
58// Canvas state operations: Replace Bitmap
59// ----------------------------------------------------------------------------
60
61class ClipCopier : public SkCanvas::ClipVisitor {
62public:
63    explicit ClipCopier(SkCanvas* dstCanvas) : m_dstCanvas(dstCanvas) {}
64
65    virtual void clipRect(const SkRect& rect, SkRegion::Op op, bool antialias) {
66        m_dstCanvas->clipRect(rect, op, antialias);
67    }
68    virtual void clipRRect(const SkRRect& rrect, SkRegion::Op op, bool antialias) {
69        m_dstCanvas->clipRRect(rrect, op, antialias);
70    }
71    virtual void clipPath(const SkPath& path, SkRegion::Op op, bool antialias) {
72        m_dstCanvas->clipPath(path, op, antialias);
73    }
74
75private:
76    SkCanvas* m_dstCanvas;
77};
78
79void SkiaCanvas::setBitmap(const SkBitmap& bitmap) {
80    sk_sp<SkCanvas> newCanvas(new SkCanvas(bitmap));
81
82    if (!bitmap.isNull()) {
83        // Copy the canvas matrix & clip state.
84        newCanvas->setMatrix(mCanvas->getTotalMatrix());
85
86        ClipCopier copier(newCanvas.get());
87        mCanvas->replayClips(&copier);
88    }
89
90    // unrefs the existing canvas
91    mCanvas = std::move(newCanvas);
92
93    // clean up the old save stack
94    mSaveStack.reset(NULL);
95}
96
97// ----------------------------------------------------------------------------
98// Canvas state operations
99// ----------------------------------------------------------------------------
100
101bool SkiaCanvas::isOpaque() {
102    return mCanvas->imageInfo().isOpaque();
103}
104
105int SkiaCanvas::width() {
106    return mCanvas->imageInfo().width();
107}
108
109int SkiaCanvas::height() {
110    return mCanvas->imageInfo().height();
111}
112
113// ----------------------------------------------------------------------------
114// Canvas state operations: Save (layer)
115// ----------------------------------------------------------------------------
116
117int SkiaCanvas::getSaveCount() const {
118    return mCanvas->getSaveCount();
119}
120
121int SkiaCanvas::save(SaveFlags::Flags flags) {
122    int count = mCanvas->save();
123    recordPartialSave(flags);
124    return count;
125}
126
127// The SkiaCanvas::restore operation layers on the capability to preserve
128// either (or both) the matrix and/or clip state after a SkCanvas::restore
129// operation. It does this by explicitly saving off the clip & matrix state
130// when requested and playing it back after the SkCanvas::restore.
131void SkiaCanvas::restore() {
132    const SaveRec* rec = (NULL == mSaveStack.get())
133            ? NULL
134            : static_cast<SaveRec*>(mSaveStack->back());
135    int currentSaveCount = mCanvas->getSaveCount();
136    SkASSERT(NULL == rec || currentSaveCount >= rec->saveCount);
137
138    if (NULL == rec || rec->saveCount != currentSaveCount) {
139        // Fast path - no record for this frame.
140        mCanvas->restore();
141        return;
142    }
143
144    bool preserveMatrix = !(rec->saveFlags & SaveFlags::Matrix);
145    bool preserveClip   = !(rec->saveFlags & SaveFlags::Clip);
146
147    SkMatrix savedMatrix;
148    if (preserveMatrix) {
149        savedMatrix = mCanvas->getTotalMatrix();
150    }
151
152    SkTArray<SkClipStack::Element> savedClips;
153    int topClipStackFrame = mCanvas->getClipStack()->getSaveCount();
154    if (preserveClip) {
155        saveClipsForFrame(savedClips, topClipStackFrame);
156    }
157
158    mCanvas->restore();
159
160    if (preserveMatrix) {
161        mCanvas->setMatrix(savedMatrix);
162    }
163
164    if (preserveClip && !savedClips.empty() &&
165        topClipStackFrame != mCanvas->getClipStack()->getSaveCount()) {
166        // Only reapply the saved clips if the top clip stack frame was actually
167        // popped by restore().  If it wasn't, it means it doesn't belong to the
168        // restored canvas frame (SkCanvas lazy save/restore kicked in).
169        applyClips(savedClips);
170    }
171
172    mSaveStack->pop_back();
173}
174
175void SkiaCanvas::restoreToCount(int restoreCount) {
176    while (mCanvas->getSaveCount() > restoreCount) {
177        this->restore();
178    }
179}
180
181static inline SkCanvas::SaveLayerFlags layerFlags(SaveFlags::Flags flags) {
182    SkCanvas::SaveLayerFlags layerFlags = 0;
183
184    // We intentionally ignore the SaveFlags::HasAlphaLayer and
185    // SkCanvas::kIsOpaque_SaveLayerFlag flags because HWUI ignores it
186    // and our Android client may use it incorrectly.
187    // In Skia, this flag is purely for performance optimization.
188
189    if (!(flags & SaveFlags::ClipToLayer)) {
190        layerFlags |= SkCanvas::kDontClipToLayer_Legacy_SaveLayerFlag;
191    }
192
193    return layerFlags;
194}
195
196int SkiaCanvas::saveLayer(float left, float top, float right, float bottom,
197            const SkPaint* paint, SaveFlags::Flags flags) {
198    const SkRect bounds = SkRect::MakeLTRB(left, top, right, bottom);
199    const SkCanvas::SaveLayerRec rec(&bounds, paint, layerFlags(flags));
200
201    int count = mCanvas->saveLayer(rec);
202    recordPartialSave(flags);
203    return count;
204}
205
206int SkiaCanvas::saveLayerAlpha(float left, float top, float right, float bottom,
207        int alpha, SaveFlags::Flags flags) {
208    if (static_cast<unsigned>(alpha) < 0xFF) {
209        SkPaint alphaPaint;
210        alphaPaint.setAlpha(alpha);
211        return this->saveLayer(left, top, right, bottom, &alphaPaint, flags);
212    }
213    return this->saveLayer(left, top, right, bottom, nullptr, flags);
214}
215
216// ----------------------------------------------------------------------------
217// functions to emulate legacy SaveFlags (i.e. independent matrix/clip flags)
218// ----------------------------------------------------------------------------
219
220void SkiaCanvas::recordPartialSave(SaveFlags::Flags flags) {
221    // A partial save is a save operation which doesn't capture the full canvas state.
222    // (either SaveFlags::Matrix or SaveFlags::Clip is missing).
223
224    // Mask-out non canvas state bits.
225    flags &= SaveFlags::MatrixClip;
226
227    if (flags == SaveFlags::MatrixClip) {
228        // not a partial save.
229        return;
230    }
231
232    if (NULL == mSaveStack.get()) {
233        mSaveStack.reset(new SkDeque(sizeof(struct SaveRec), 8));
234    }
235
236    SaveRec* rec = static_cast<SaveRec*>(mSaveStack->push_back());
237    rec->saveCount = mCanvas->getSaveCount();
238    rec->saveFlags = flags;
239}
240
241void SkiaCanvas::saveClipsForFrame(SkTArray<SkClipStack::Element>& clips,
242                                   int saveCountToBackup) {
243    // Each SkClipStack::Element stores the index of the canvas save
244    // with which it is associated. Backup only those Elements that
245    // are associated with 'saveCountToBackup'
246    SkClipStack::Iter clipIterator(*mCanvas->getClipStack(),
247                                   SkClipStack::Iter::kTop_IterStart);
248    while (const SkClipStack::Element* elem = clipIterator.prev()) {
249        if (elem->getSaveCount() < saveCountToBackup) {
250            // done with the target save count.
251            break;
252        }
253        SkASSERT(elem->getSaveCount() == saveCountToBackup);
254        clips.push_back(*elem);
255    }
256}
257
258void SkiaCanvas::applyClips(const SkTArray<SkClipStack::Element>& clips) {
259    ClipCopier clipCopier(mCanvas.get());
260
261    // The clip stack stores clips in device space.
262    SkMatrix origMatrix = mCanvas->getTotalMatrix();
263    mCanvas->resetMatrix();
264
265    // We pushed the clips in reverse order.
266    for (int i = clips.count() - 1; i >= 0; --i) {
267        clips[i].replay(&clipCopier);
268    }
269
270    mCanvas->setMatrix(origMatrix);
271}
272
273// ----------------------------------------------------------------------------
274// Canvas state operations: Matrix
275// ----------------------------------------------------------------------------
276
277void SkiaCanvas::getMatrix(SkMatrix* outMatrix) const {
278    *outMatrix = mCanvas->getTotalMatrix();
279}
280
281void SkiaCanvas::setMatrix(const SkMatrix& matrix) {
282    mCanvas->setMatrix(matrix);
283}
284
285void SkiaCanvas::concat(const SkMatrix& matrix) {
286    mCanvas->concat(matrix);
287}
288
289void SkiaCanvas::rotate(float degrees) {
290    mCanvas->rotate(degrees);
291}
292
293void SkiaCanvas::scale(float sx, float sy) {
294    mCanvas->scale(sx, sy);
295}
296
297void SkiaCanvas::skew(float sx, float sy) {
298    mCanvas->skew(sx, sy);
299}
300
301void SkiaCanvas::translate(float dx, float dy) {
302    mCanvas->translate(dx, dy);
303}
304
305// ----------------------------------------------------------------------------
306// Canvas state operations: Clips
307// ----------------------------------------------------------------------------
308
309// This function is a mirror of SkCanvas::getClipBounds except that it does
310// not outset the edge of the clip to account for anti-aliasing. There is
311// a skia bug to investigate pushing this logic into back into skia.
312// (see https://code.google.com/p/skia/issues/detail?id=1303)
313bool SkiaCanvas::getClipBounds(SkRect* outRect) const {
314    SkIRect ibounds;
315    if (!mCanvas->getClipDeviceBounds(&ibounds)) {
316        return false;
317    }
318
319    SkMatrix inverse;
320    // if we can't invert the CTM, we can't return local clip bounds
321    if (!mCanvas->getTotalMatrix().invert(&inverse)) {
322        if (outRect) {
323            outRect->setEmpty();
324        }
325        return false;
326    }
327
328    if (NULL != outRect) {
329        SkRect r = SkRect::Make(ibounds);
330        inverse.mapRect(outRect, r);
331    }
332    return true;
333}
334
335bool SkiaCanvas::quickRejectRect(float left, float top, float right, float bottom) const {
336    SkRect bounds = SkRect::MakeLTRB(left, top, right, bottom);
337    return mCanvas->quickReject(bounds);
338}
339
340bool SkiaCanvas::quickRejectPath(const SkPath& path) const {
341    return mCanvas->quickReject(path);
342}
343
344bool SkiaCanvas::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
345    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
346    mCanvas->clipRect(rect, op);
347    return !mCanvas->isClipEmpty();
348}
349
350bool SkiaCanvas::clipPath(const SkPath* path, SkRegion::Op op) {
351    SkRRect roundRect;
352    if (path->isRRect(&roundRect)) {
353        mCanvas->clipRRect(roundRect, op);
354    } else {
355        mCanvas->clipPath(*path, op);
356    }
357    return !mCanvas->isClipEmpty();
358}
359
360bool SkiaCanvas::clipRegion(const SkRegion* region, SkRegion::Op op) {
361    SkPath rgnPath;
362    if (region->getBoundaryPath(&rgnPath)) {
363        // The region is specified in device space.
364        SkMatrix savedMatrix = mCanvas->getTotalMatrix();
365        mCanvas->resetMatrix();
366        mCanvas->clipPath(rgnPath, op);
367        mCanvas->setMatrix(savedMatrix);
368    } else {
369        mCanvas->clipRect(SkRect::MakeEmpty(), op);
370    }
371    return !mCanvas->isClipEmpty();
372}
373
374// ----------------------------------------------------------------------------
375// Canvas state operations: Filters
376// ----------------------------------------------------------------------------
377
378SkDrawFilter* SkiaCanvas::getDrawFilter() {
379    return mCanvas->getDrawFilter();
380}
381
382void SkiaCanvas::setDrawFilter(SkDrawFilter* drawFilter) {
383    mCanvas->setDrawFilter(drawFilter);
384}
385
386// ----------------------------------------------------------------------------
387// Canvas draw operations
388// ----------------------------------------------------------------------------
389
390void SkiaCanvas::drawColor(int color, SkBlendMode mode) {
391    mCanvas->drawColor(color, mode);
392}
393
394void SkiaCanvas::drawPaint(const SkPaint& paint) {
395    mCanvas->drawPaint(paint);
396}
397
398// ----------------------------------------------------------------------------
399// Canvas draw operations: Geometry
400// ----------------------------------------------------------------------------
401
402void SkiaCanvas::drawPoints(const float* points, int count, const SkPaint& paint,
403                            SkCanvas::PointMode mode) {
404    // convert the floats into SkPoints
405    count >>= 1;    // now it is the number of points
406    std::unique_ptr<SkPoint[]> pts(new SkPoint[count]);
407    for (int i = 0; i < count; i++) {
408        pts[i].set(points[0], points[1]);
409        points += 2;
410    }
411    mCanvas->drawPoints(mode, count, pts.get(), paint);
412}
413
414
415void SkiaCanvas::drawPoint(float x, float y, const SkPaint& paint) {
416    mCanvas->drawPoint(x, y, paint);
417}
418
419void SkiaCanvas::drawPoints(const float* points, int count, const SkPaint& paint) {
420    this->drawPoints(points, count, paint, SkCanvas::kPoints_PointMode);
421}
422
423void SkiaCanvas::drawLine(float startX, float startY, float stopX, float stopY,
424                          const SkPaint& paint) {
425    mCanvas->drawLine(startX, startY, stopX, stopY, paint);
426}
427
428void SkiaCanvas::drawLines(const float* points, int count, const SkPaint& paint) {
429    this->drawPoints(points, count, paint, SkCanvas::kLines_PointMode);
430}
431
432void SkiaCanvas::drawRect(float left, float top, float right, float bottom,
433        const SkPaint& paint) {
434    mCanvas->drawRectCoords(left, top, right, bottom, paint);
435
436}
437
438void SkiaCanvas::drawRegion(const SkRegion& region, const SkPaint& paint) {
439    SkRegion::Iterator it(region);
440    while (!it.done()) {
441        mCanvas->drawRect(SkRect::Make(it.rect()), paint);
442        it.next();
443    }
444}
445
446void SkiaCanvas::drawRoundRect(float left, float top, float right, float bottom,
447        float rx, float ry, const SkPaint& paint) {
448    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
449    mCanvas->drawRoundRect(rect, rx, ry, paint);
450}
451
452void SkiaCanvas::drawCircle(float x, float y, float radius, const SkPaint& paint) {
453    mCanvas->drawCircle(x, y, radius, paint);
454}
455
456void SkiaCanvas::drawOval(float left, float top, float right, float bottom, const SkPaint& paint) {
457    SkRect oval = SkRect::MakeLTRB(left, top, right, bottom);
458    mCanvas->drawOval(oval, paint);
459}
460
461void SkiaCanvas::drawArc(float left, float top, float right, float bottom,
462        float startAngle, float sweepAngle, bool useCenter, const SkPaint& paint) {
463    SkRect arc = SkRect::MakeLTRB(left, top, right, bottom);
464    mCanvas->drawArc(arc, startAngle, sweepAngle, useCenter, paint);
465}
466
467void SkiaCanvas::drawPath(const SkPath& path, const SkPaint& paint) {
468    SkRect rect;
469    SkRRect roundRect;
470    if (path.isOval(&rect)) {
471        mCanvas->drawOval(rect, paint);
472    } else if (path.isRRect(&roundRect)) {
473        mCanvas->drawRRect(roundRect, paint);
474    } else {
475        mCanvas->drawPath(path, paint);
476    }
477}
478
479void SkiaCanvas::drawVertices(SkCanvas::VertexMode vertexMode, int vertexCount,
480                              const float* verts, const float* texs, const int* colors,
481                              const uint16_t* indices, int indexCount, const SkPaint& paint) {
482#ifndef SK_SCALAR_IS_FLOAT
483    SkDEBUGFAIL("SkScalar must be a float for these conversions to be valid");
484#endif
485    const int ptCount = vertexCount >> 1;
486    mCanvas->drawVertices(vertexMode, ptCount, (SkPoint*)verts, (SkPoint*)texs,
487                          (SkColor*)colors, NULL, indices, indexCount, paint);
488}
489
490// ----------------------------------------------------------------------------
491// Canvas draw operations: Bitmaps
492// ----------------------------------------------------------------------------
493
494void SkiaCanvas::drawBitmap(Bitmap& bitmap, float left, float top, const SkPaint* paint) {
495    SkBitmap skBitmap;
496    bitmap.getSkBitmap(&skBitmap);
497    mCanvas->drawBitmap(skBitmap, left, top, paint);
498}
499
500void SkiaCanvas::drawBitmap(const SkBitmap& bitmap, const SkMatrix& matrix, const SkPaint* paint) {
501    SkAutoCanvasRestore acr(mCanvas.get(), true);
502    mCanvas->concat(matrix);
503    mCanvas->drawBitmap(bitmap, 0, 0, paint);
504}
505
506void SkiaCanvas::drawBitmap(const SkBitmap& bitmap, float srcLeft, float srcTop,
507                            float srcRight, float srcBottom, float dstLeft, float dstTop,
508                            float dstRight, float dstBottom, const SkPaint* paint) {
509    SkRect srcRect = SkRect::MakeLTRB(srcLeft, srcTop, srcRight, srcBottom);
510    SkRect dstRect = SkRect::MakeLTRB(dstLeft, dstTop, dstRight, dstBottom);
511    mCanvas->drawBitmapRect(bitmap, srcRect, dstRect, paint);
512}
513
514void SkiaCanvas::drawBitmapMesh(const SkBitmap& bitmap, int meshWidth, int meshHeight,
515        const float* vertices, const int* colors, const SkPaint* paint) {
516
517    const int ptCount = (meshWidth + 1) * (meshHeight + 1);
518    const int indexCount = meshWidth * meshHeight * 6;
519
520    /*  Our temp storage holds 2 or 3 arrays.
521        texture points [ptCount * sizeof(SkPoint)]
522        optionally vertex points [ptCount * sizeof(SkPoint)] if we need a
523            copy to convert from float to fixed
524        indices [ptCount * sizeof(uint16_t)]
525    */
526    ssize_t storageSize = ptCount * sizeof(SkPoint); // texs[]
527    storageSize += indexCount * sizeof(uint16_t);  // indices[]
528
529
530#ifndef SK_SCALAR_IS_FLOAT
531    SkDEBUGFAIL("SkScalar must be a float for these conversions to be valid");
532#endif
533    std::unique_ptr<char[]> storage(new char[storageSize]);
534    SkPoint* texs = (SkPoint*)storage.get();
535    uint16_t* indices = (uint16_t*)(texs + ptCount);
536
537    // cons up texture coordinates and indices
538    {
539        const SkScalar w = SkIntToScalar(bitmap.width());
540        const SkScalar h = SkIntToScalar(bitmap.height());
541        const SkScalar dx = w / meshWidth;
542        const SkScalar dy = h / meshHeight;
543
544        SkPoint* texsPtr = texs;
545        SkScalar y = 0;
546        for (int i = 0; i <= meshHeight; i++) {
547            if (i == meshHeight) {
548                y = h;  // to ensure numerically we hit h exactly
549            }
550            SkScalar x = 0;
551            for (int j = 0; j < meshWidth; j++) {
552                texsPtr->set(x, y);
553                texsPtr += 1;
554                x += dx;
555            }
556            texsPtr->set(w, y);
557            texsPtr += 1;
558            y += dy;
559        }
560        SkASSERT(texsPtr - texs == ptCount);
561    }
562
563    // cons up indices
564    {
565        uint16_t* indexPtr = indices;
566        int index = 0;
567        for (int i = 0; i < meshHeight; i++) {
568            for (int j = 0; j < meshWidth; j++) {
569                // lower-left triangle
570                *indexPtr++ = index;
571                *indexPtr++ = index + meshWidth + 1;
572                *indexPtr++ = index + meshWidth + 2;
573                // upper-right triangle
574                *indexPtr++ = index;
575                *indexPtr++ = index + meshWidth + 2;
576                *indexPtr++ = index + 1;
577                // bump to the next cell
578                index += 1;
579            }
580            // bump to the next row
581            index += 1;
582        }
583        SkASSERT(indexPtr - indices == indexCount);
584        SkASSERT((char*)indexPtr - (char*)storage.get() == storageSize);
585    }
586
587    // double-check that we have legal indices
588#ifdef SK_DEBUG
589    {
590        for (int i = 0; i < indexCount; i++) {
591            SkASSERT((unsigned)indices[i] < (unsigned)ptCount);
592        }
593    }
594#endif
595
596    // cons-up a shader for the bitmap
597    SkPaint tmpPaint;
598    if (paint) {
599        tmpPaint = *paint;
600    }
601    sk_sp<SkShader> shader = SkMakeBitmapShader(bitmap,
602                                                SkShader::kClamp_TileMode,
603                                                SkShader::kClamp_TileMode,
604                                                nullptr,
605                                                kNever_SkCopyPixelsMode,
606                                                nullptr);
607    tmpPaint.setShader(std::move(shader));
608
609    mCanvas->drawVertices(SkCanvas::kTriangles_VertexMode, ptCount, (SkPoint*)vertices,
610                         texs, (const SkColor*)colors, NULL, indices,
611                         indexCount, tmpPaint);
612}
613
614void SkiaCanvas::drawNinePatch(const SkBitmap& bitmap, const Res_png_9patch& chunk,
615        float dstLeft, float dstTop, float dstRight, float dstBottom, const SkPaint* paint) {
616    SkRect bounds = SkRect::MakeLTRB(dstLeft, dstTop, dstRight, dstBottom);
617    NinePatch::Draw(mCanvas.get(), bounds, bitmap, chunk, paint, nullptr);
618}
619
620void SkiaCanvas::drawVectorDrawable(VectorDrawableRoot* vectorDrawable) {
621    vectorDrawable->drawStaging(this);
622}
623
624// ----------------------------------------------------------------------------
625// Canvas draw operations: Text
626// ----------------------------------------------------------------------------
627
628void SkiaCanvas::drawGlyphs(const uint16_t* text, const float* positions, int count,
629        const SkPaint& paint, float x, float y,
630        float boundsLeft, float boundsTop, float boundsRight, float boundsBottom,
631        float totalAdvance) {
632    static_assert(sizeof(SkPoint) == sizeof(float)*2, "SkPoint is no longer two floats");
633    mCanvas->drawPosText(text, count << 1, reinterpret_cast<const SkPoint*>(positions), paint);
634    drawTextDecorations(x, y, totalAdvance, paint);
635}
636
637void SkiaCanvas::drawLayoutOnPath(const minikin::Layout& layout, float hOffset, float vOffset,
638        const SkPaint& paint, const SkPath& path, size_t start, size_t end) {
639    const int N = end - start;
640    SkAutoSMalloc<1024> storage(N * (sizeof(uint16_t) + sizeof(SkRSXform)));
641    SkRSXform* xform = (SkRSXform*)storage.get();
642    uint16_t* glyphs = (uint16_t*)(xform + N);
643    SkPathMeasure meas(path, false);
644
645    for (size_t i = start; i < end; i++) {
646        glyphs[i - start] = layout.getGlyphId(i);
647        float x = hOffset + layout.getX(i);
648        float y = vOffset + layout.getY(i);
649
650        SkPoint pos;
651        SkVector tan;
652        if (!meas.getPosTan(x, &pos, &tan)) {
653            pos.set(x, y);
654            tan.set(1, 0);
655        }
656        xform[i - start].fSCos = tan.x();
657        xform[i - start].fSSin = tan.y();
658        xform[i - start].fTx   = pos.x() - tan.y() * y;
659        xform[i - start].fTy   = pos.y() + tan.x() * y;
660    }
661
662    this->asSkCanvas()->drawTextRSXform(glyphs, sizeof(uint16_t) * N, xform, nullptr, paint);
663}
664
665// ----------------------------------------------------------------------------
666// Canvas draw operations: Animations
667// ----------------------------------------------------------------------------
668
669class AnimatedRoundRect : public SkDrawable {
670 public:
671    AnimatedRoundRect(uirenderer::CanvasPropertyPrimitive* left,
672            uirenderer::CanvasPropertyPrimitive* top, uirenderer::CanvasPropertyPrimitive* right,
673            uirenderer::CanvasPropertyPrimitive* bottom, uirenderer::CanvasPropertyPrimitive* rx,
674            uirenderer::CanvasPropertyPrimitive* ry, uirenderer::CanvasPropertyPaint* p) :
675            mLeft(left), mTop(top), mRight(right), mBottom(bottom), mRx(rx), mRy(ry), mPaint(p) {}
676
677 protected:
678     virtual SkRect onGetBounds() override {
679         return SkRect::MakeLTRB(mLeft->value, mTop->value, mRight->value, mBottom->value);
680     }
681     virtual void onDraw(SkCanvas* canvas) override {
682         SkRect rect = SkRect::MakeLTRB(mLeft->value, mTop->value, mRight->value, mBottom->value);
683         canvas->drawRoundRect(rect, mRx->value, mRy->value, mPaint->value);
684     }
685
686 private:
687    sp<uirenderer::CanvasPropertyPrimitive> mLeft;
688    sp<uirenderer::CanvasPropertyPrimitive> mTop;
689    sp<uirenderer::CanvasPropertyPrimitive> mRight;
690    sp<uirenderer::CanvasPropertyPrimitive> mBottom;
691    sp<uirenderer::CanvasPropertyPrimitive> mRx;
692    sp<uirenderer::CanvasPropertyPrimitive> mRy;
693    sp<uirenderer::CanvasPropertyPaint> mPaint;
694};
695
696class AnimatedCircle : public SkDrawable {
697 public:
698    AnimatedCircle(uirenderer::CanvasPropertyPrimitive* x, uirenderer::CanvasPropertyPrimitive* y,
699            uirenderer::CanvasPropertyPrimitive* radius, uirenderer::CanvasPropertyPaint* paint) :
700            mX(x), mY(y), mRadius(radius), mPaint(paint) {}
701
702 protected:
703     virtual SkRect onGetBounds() override {
704         const float x = mX->value;
705         const float y = mY->value;
706         const float radius = mRadius->value;
707         return SkRect::MakeLTRB(x - radius, y - radius, x + radius, y + radius);
708     }
709     virtual void onDraw(SkCanvas* canvas) override {
710         canvas->drawCircle(mX->value, mY->value, mRadius->value, mPaint->value);
711     }
712
713 private:
714    sp<uirenderer::CanvasPropertyPrimitive> mX;
715    sp<uirenderer::CanvasPropertyPrimitive> mY;
716    sp<uirenderer::CanvasPropertyPrimitive> mRadius;
717    sp<uirenderer::CanvasPropertyPaint> mPaint;
718};
719
720void SkiaCanvas::drawRoundRect(uirenderer::CanvasPropertyPrimitive* left,
721        uirenderer::CanvasPropertyPrimitive* top, uirenderer::CanvasPropertyPrimitive* right,
722        uirenderer::CanvasPropertyPrimitive* bottom, uirenderer::CanvasPropertyPrimitive* rx,
723        uirenderer::CanvasPropertyPrimitive* ry, uirenderer::CanvasPropertyPaint* paint) {
724    sk_sp<AnimatedRoundRect> drawable(
725            new AnimatedRoundRect(left, top, right, bottom, rx, ry, paint));
726    mCanvas->drawDrawable(drawable.get());
727}
728
729void SkiaCanvas::drawCircle(uirenderer::CanvasPropertyPrimitive* x, uirenderer::CanvasPropertyPrimitive* y,
730        uirenderer::CanvasPropertyPrimitive* radius, uirenderer::CanvasPropertyPaint* paint) {
731    sk_sp<AnimatedCircle> drawable(new AnimatedCircle(x, y, radius, paint));
732    mCanvas->drawDrawable(drawable.get());
733}
734
735// ----------------------------------------------------------------------------
736// Canvas draw operations: View System
737// ----------------------------------------------------------------------------
738
739void SkiaCanvas::drawLayer(uirenderer::DeferredLayerUpdater* layer) {
740    LOG_ALWAYS_FATAL("SkiaCanvas can't directly draw Layers");
741}
742
743void SkiaCanvas::drawRenderNode(uirenderer::RenderNode* renderNode) {
744    LOG_ALWAYS_FATAL("SkiaCanvas can't directly draw RenderNodes");
745}
746
747void SkiaCanvas::callDrawGLFunction(Functor* functor,
748        uirenderer::GlFunctorLifecycleListener* listener) {
749    LOG_ALWAYS_FATAL("SkiaCanvas can't directly draw GL Content");
750}
751
752} // namespace android
753