| /* |
| * Copyright 2017 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkThreadedBMPDevice.h" |
| |
| #include "SkPath.h" |
| #include "SkTaskGroup.h" |
| #include "SkVertices.h" |
| |
| #include <mutex> |
| #include <vector> |
| |
| constexpr int MAX_CACHE_LINE = 64; |
| |
| // Some basic logics and data structures that are shared across the current experimental schedulers. |
| class TiledDrawSchedulerBase : public TiledDrawScheduler { |
| public: |
| TiledDrawSchedulerBase(int tiles, WorkFunc work) |
| : fTileCnt(tiles), fIsFinishing(false), fDrawCnt(0), fWork(std::move(work)) {} |
| |
| void signal() override { |
| fDrawCnt++; |
| } |
| void finish() override { |
| fIsFinishing.store(true, std::memory_order_relaxed); |
| } |
| |
| protected: |
| const int fTileCnt; |
| std::atomic<bool> fIsFinishing; |
| std::atomic<int> fDrawCnt; |
| WorkFunc fWork; |
| }; |
| |
| class TiledDrawSchedulerBySpinning : public TiledDrawSchedulerBase { |
| public: |
| TiledDrawSchedulerBySpinning(int tiles, WorkFunc work) |
| : TiledDrawSchedulerBase(tiles, std::move(work)), fScheduleData(tiles) {} |
| |
| void signal() final { this->TiledDrawSchedulerBase::signal(); } |
| void finish() final { this->TiledDrawSchedulerBase::finish(); } |
| |
| bool next(int& tileIndex) final { |
| int& drawIndex = fScheduleData[tileIndex].fDrawIndex; |
| SkASSERT(drawIndex <= fDrawCnt); |
| while (true) { |
| bool isFinishing = fIsFinishing.load(std::memory_order_relaxed); |
| if (isFinishing && drawIndex >= fDrawCnt) { |
| return false; |
| } else if (drawIndex < fDrawCnt) { |
| fWork(tileIndex, drawIndex++); |
| return true; |
| } |
| } |
| } |
| |
| private: |
| // alignas(MAX_CACHE_LINE) to avoid false sharing by cache lines |
| struct alignas(MAX_CACHE_LINE) TileScheduleData { |
| TileScheduleData() : fDrawIndex(0) {} |
| |
| int fDrawIndex; // next draw index for this tile |
| }; |
| |
| std::vector<TileScheduleData> fScheduleData; |
| }; |
| |
| class TiledDrawSchedulerFlexible : public TiledDrawSchedulerBase { |
| public: |
| TiledDrawSchedulerFlexible(int tiles, WorkFunc work) |
| : TiledDrawSchedulerBase(tiles, std::move(work)), fScheduleData(tiles) {} |
| |
| void signal() final { this->TiledDrawSchedulerBase::signal(); } |
| void finish() final { this->TiledDrawSchedulerBase::finish(); } |
| |
| bool next(int& tileIndex) final { |
| int failCnt = 0; |
| while (true) { |
| TileScheduleData& scheduleData = fScheduleData[tileIndex]; |
| bool locked = scheduleData.fMutex.try_lock(); |
| bool processed = false; |
| |
| if (locked) { |
| if (scheduleData.fDrawIndex < fDrawCnt) { |
| fWork(tileIndex, scheduleData.fDrawIndex++); |
| processed = true; |
| } else { |
| failCnt += fIsFinishing.load(std::memory_order_relaxed); |
| } |
| scheduleData.fMutex.unlock(); |
| } |
| |
| if (processed) { |
| return true; |
| } else { |
| if (failCnt >= fTileCnt) { |
| return false; |
| } |
| tileIndex = (tileIndex + 1) % fTileCnt; |
| } |
| } |
| } |
| |
| private: |
| // alignas(MAX_CACHE_LINE) to avoid false sharing by cache lines |
| struct alignas(MAX_CACHE_LINE) TileScheduleData { |
| TileScheduleData() : fDrawIndex(0) {} |
| |
| int fDrawIndex; // next draw index for this tile |
| std::mutex fMutex; // the mutex for the thread to acquire |
| }; |
| |
| std::vector<TileScheduleData> fScheduleData; |
| }; |
| |
| class TiledDrawSchedulerBySemaphores : public TiledDrawSchedulerBase { |
| public: |
| TiledDrawSchedulerBySemaphores(int tiles, WorkFunc work) |
| : TiledDrawSchedulerBase(tiles, std::move(work)), fScheduleData(tiles) {} |
| |
| |
| void signal() final { |
| this->TiledDrawSchedulerBase::signal(); |
| signalRoot(); |
| } |
| |
| void finish() final { |
| this->TiledDrawSchedulerBase::finish(); |
| signalRoot(); |
| } |
| |
| bool next(int& tileIndex) final { |
| SkASSERT(tileIndex >= 0 && tileIndex < fTileCnt); |
| TileScheduleData& scheduleData = fScheduleData[tileIndex]; |
| while (true) { |
| scheduleData.fSemaphore.wait(); |
| int leftChild = (tileIndex + 1) * 2 - 1; |
| int rightChild = leftChild + 1; |
| if (leftChild < fTileCnt) { |
| fScheduleData[leftChild].fSemaphore.signal(); |
| } |
| if (rightChild < fTileCnt) { |
| fScheduleData[rightChild].fSemaphore.signal(); |
| } |
| |
| bool isFinishing = fIsFinishing.load(std::memory_order_relaxed); |
| if (isFinishing && scheduleData.fDrawIndex >= fDrawCnt) { |
| return false; |
| } else { |
| SkASSERT(scheduleData.fDrawIndex < fDrawCnt); |
| fWork(tileIndex, scheduleData.fDrawIndex++); |
| return true; |
| } |
| } |
| } |
| |
| private: |
| // alignas(MAX_CACHE_LINE) to avoid false sharing by cache lines |
| struct alignas(MAX_CACHE_LINE) TileScheduleData { |
| TileScheduleData() : fDrawIndex(0) {} |
| |
| int fDrawIndex; |
| SkSemaphore fSemaphore; |
| }; |
| |
| void signalRoot() { |
| SkASSERT(fTileCnt > 0); |
| fScheduleData[0].fSemaphore.signal(); |
| } |
| |
| std::vector<TileScheduleData> fScheduleData; |
| }; |
| |
| void SkThreadedBMPDevice::startThreads() { |
| SkASSERT(fThreadFutures.count() == 0); |
| SkASSERT(fQueueSize == 0); |
| |
| TiledDrawScheduler::WorkFunc work = [this](int tileIndex, int drawIndex){ |
| auto& element = fQueue[drawIndex]; |
| if (SkIRect::Intersects(fTileBounds[tileIndex], element.fDrawBounds)) { |
| element.fDrawFn(fTileBounds[tileIndex]); |
| } |
| }; |
| |
| // using Scheduler = TiledDrawSchedulerBySemaphores; |
| // using Scheduler = TiledDrawSchedulerBySpinning; |
| using Scheduler = TiledDrawSchedulerFlexible; |
| fScheduler.reset(new Scheduler(fTileCnt, work)); |
| for(int i = 0; i < fThreadCnt; ++i) { |
| fThreadFutures.push_back(std::async(std::launch::async, [this, i]() { |
| int tileIndex = i; |
| while (fScheduler->next(tileIndex)) {} |
| })); |
| } |
| } |
| |
| void SkThreadedBMPDevice::finishThreads() { |
| fScheduler->finish(); |
| for(auto& future : fThreadFutures) { |
| future.wait(); |
| } |
| fThreadFutures.reset(); |
| fQueueSize = 0; |
| fScheduler.reset(nullptr); |
| } |
| |
| SkThreadedBMPDevice::SkThreadedBMPDevice(const SkBitmap& bitmap, int tiles, int threads) |
| : INHERITED(bitmap) |
| , fTileCnt(tiles) |
| , fThreadCnt(threads <= 0 ? tiles : threads) |
| { |
| // Tiling using stripes for now; we'll explore better tiling in the future. |
| int h = (bitmap.height() + fTileCnt - 1) / SkTMax(fTileCnt, 1); |
| int w = bitmap.width(); |
| int top = 0; |
| for(int tid = 0; tid < fTileCnt; ++tid, top += h) { |
| fTileBounds.push_back(SkIRect::MakeLTRB(0, top, w, top + h)); |
| } |
| fQueueSize = 0; |
| startThreads(); |
| } |
| |
| void SkThreadedBMPDevice::flush() { |
| finishThreads(); |
| startThreads(); |
| } |
| |
| // Having this captured in lambda seems to be faster than saving this in DrawElement |
| struct SkThreadedBMPDevice::DrawState { |
| SkPixmap fDst; |
| SkMatrix fMatrix; |
| SkRasterClip fRC; |
| |
| explicit DrawState(SkThreadedBMPDevice* dev) { |
| // we need fDst to be set, and if we're actually drawing, to dirty the genID |
| if (!dev->accessPixels(&fDst)) { |
| // NoDrawDevice uses us (why?) so we have to catch this case w/ no pixels |
| fDst.reset(dev->imageInfo(), nullptr, 0); |
| } |
| fMatrix = dev->ctm(); |
| fRC = dev->fRCStack.rc(); |
| } |
| |
| SkDraw getThreadDraw(SkRasterClip& threadRC, const SkIRect& threadBounds) const { |
| SkDraw draw; |
| draw.fDst = fDst; |
| draw.fMatrix = &fMatrix; |
| threadRC = fRC; |
| threadRC.op(threadBounds, SkRegion::kIntersect_Op); |
| draw.fRC = &threadRC; |
| return draw; |
| } |
| }; |
| |
| SkIRect SkThreadedBMPDevice::transformDrawBounds(const SkRect& drawBounds) const { |
| if (drawBounds.isLargest()) { |
| return SkIRect::MakeLargest(); |
| } |
| SkRect transformedBounds; |
| this->ctm().mapRect(&transformedBounds, drawBounds); |
| return transformedBounds.roundOut(); |
| } |
| |
| // The do {...} while (false) is to enforce trailing semicolon as suggested by mtklein@ |
| #define THREADED_DRAW(drawBounds, actualDrawCall) \ |
| do { \ |
| DrawState ds(this); \ |
| SkASSERT(fQueueSize < MAX_QUEUE_SIZE); \ |
| fQueue[fQueueSize++] = { \ |
| this->transformDrawBounds(drawBounds), \ |
| [=](const SkIRect& tileBounds) { \ |
| SkRasterClip tileRC; \ |
| SkDraw draw = ds.getThreadDraw(tileRC, tileBounds); \ |
| draw.actualDrawCall; \ |
| }, \ |
| }; \ |
| fScheduler->signal(); \ |
| } while (false) |
| |
| static inline SkRect get_fast_bounds(const SkRect& r, const SkPaint& p) { |
| SkRect result; |
| if (p.canComputeFastBounds()) { |
| result = p.computeFastBounds(r, &result); |
| } else { |
| result = SkRect::MakeLargest(); |
| } |
| return result; |
| } |
| |
| void SkThreadedBMPDevice::drawPaint(const SkPaint& paint) { |
| THREADED_DRAW(SkRect::MakeLargest(), drawPaint(paint)); |
| } |
| |
| void SkThreadedBMPDevice::drawPoints(SkCanvas::PointMode mode, size_t count, |
| const SkPoint pts[], const SkPaint& paint) { |
| // TODO tighter drawBounds |
| SkRect drawBounds = SkRect::MakeLargest(); |
| THREADED_DRAW(drawBounds, drawPoints(mode, count, pts, paint, nullptr)); |
| } |
| |
| void SkThreadedBMPDevice::drawRect(const SkRect& r, const SkPaint& paint) { |
| SkRect drawBounds = get_fast_bounds(r, paint); |
| THREADED_DRAW(drawBounds, drawRect(r, paint)); |
| } |
| |
| void SkThreadedBMPDevice::drawRRect(const SkRRect& rrect, const SkPaint& paint) { |
| #ifdef SK_IGNORE_BLURRED_RRECT_OPT |
| SkPath path; |
| |
| path.addRRect(rrect); |
| // call the VIRTUAL version, so any subclasses who do handle drawPath aren't |
| // required to override drawRRect. |
| this->drawPath(path, paint, nullptr, false); |
| #else |
| SkRect drawBounds = get_fast_bounds(rrect.getBounds(), paint); |
| THREADED_DRAW(drawBounds, drawRRect(rrect, paint)); |
| #endif |
| } |
| |
| void SkThreadedBMPDevice::drawPath(const SkPath& path, const SkPaint& paint, |
| const SkMatrix* prePathMatrix, bool pathIsMutable) { |
| SkRect drawBounds = path.isInverseFillType() ? SkRect::MakeLargest() |
| : get_fast_bounds(path.getBounds(), paint); |
| // For thread safety, make path imutable |
| THREADED_DRAW(drawBounds, drawPath(path, paint, prePathMatrix, false)); |
| } |
| |
| void SkThreadedBMPDevice::drawBitmap(const SkBitmap& bitmap, SkScalar x, SkScalar y, |
| const SkPaint& paint) { |
| SkMatrix matrix = SkMatrix::MakeTrans(x, y); |
| LogDrawScaleFactor(SkMatrix::Concat(this->ctm(), matrix), paint.getFilterQuality()); |
| SkRect drawBounds = SkRect::MakeWH(bitmap.width(), bitmap.height()); |
| matrix.mapRect(&drawBounds); |
| THREADED_DRAW(drawBounds, drawBitmap(bitmap, matrix, nullptr, paint)); |
| } |
| |
| void SkThreadedBMPDevice::drawSprite(const SkBitmap& bitmap, int x, int y, const SkPaint& paint) { |
| SkRect drawBounds = SkRect::MakeXYWH(x, y, bitmap.width(), bitmap.height()); |
| THREADED_DRAW(drawBounds, drawSprite(bitmap, x, y, paint)); |
| } |
| |
| void SkThreadedBMPDevice::drawText(const void* text, size_t len, SkScalar x, SkScalar y, |
| const SkPaint& paint) { |
| SkRect drawBounds = SkRect::MakeLargest(); // TODO tighter drawBounds |
| THREADED_DRAW(drawBounds, drawText((const char*)text, len, x, y, paint, &this->surfaceProps())); |
| } |
| |
| void SkThreadedBMPDevice::drawPosText(const void* text, size_t len, const SkScalar xpos[], |
| int scalarsPerPos, const SkPoint& offset, const SkPaint& paint) { |
| SkRect drawBounds = SkRect::MakeLargest(); // TODO tighter drawBounds |
| THREADED_DRAW(drawBounds, drawPosText((const char*)text, len, xpos, scalarsPerPos, offset, |
| paint, &surfaceProps())); |
| } |
| |
| void SkThreadedBMPDevice::drawVertices(const SkVertices* vertices, SkBlendMode bmode, |
| const SkPaint& paint) { |
| SkRect drawBounds = SkRect::MakeLargest(); // TODO tighter drawBounds |
| THREADED_DRAW(drawBounds, drawVertices(vertices->mode(), vertices->vertexCount(), |
| vertices->positions(), vertices->texCoords(), |
| vertices->colors(), bmode, vertices->indices(), |
| vertices->indexCount(), paint)); |
| } |
| |
| void SkThreadedBMPDevice::drawDevice(SkBaseDevice* device, int x, int y, const SkPaint& paint) { |
| SkASSERT(!paint.getImageFilter()); |
| SkRect drawBounds = SkRect::MakeXYWH(x, y, device->width(), device->height()); |
| THREADED_DRAW(drawBounds, |
| drawSprite(static_cast<SkBitmapDevice*>(device)->fBitmap, x, y, paint)); |
| } |
