C++ SkSize::width方法代码示例

    void drawHere(SkCanvas* canvas, SkFilterQuality filter, SkScalar dx, SkScalar dy) {
        SkCanvas* origCanvas = canvas;
        SkAutoCanvasRestore acr(canvas, true);

        SkISize size = SkISize::Make(fImage->width(), fImage->height());

        SkAutoTUnref<SkSurface> surface;
        if (fShowFatBits) {
            // scale up so we don't clip rotations
            SkImageInfo info = SkImageInfo::MakeN32(fImage->width() * 2, fImage->height() * 2,
                                                    kOpaque_SkAlphaType);
            surface.reset(make_surface(canvas, info));
            canvas = surface->getCanvas();
            canvas->drawColor(SK_ColorWHITE);
            size.set(info.width(), info.height());
        } else {
            canvas->translate(SkScalarHalf(fCell.width() - fImage->width()),
                              SkScalarHalf(fCell.height() - fImage->height()));
        }
        this->drawTheImage(canvas, size, filter, dx, dy);

        if (surface) {
            SkAutoTUnref<SkImage> orig(surface->newImageSnapshot());
            SkAutoTUnref<SkImage> zoomed(zoom_up(orig));
            origCanvas->drawImage(zoomed,
                                  SkScalarHalf(fCell.width() - zoomed->width()),
                                  SkScalarHalf(fCell.height() - zoomed->height()));
        }
    }

    int checkOval(int* flatCount, int* buldgeCount) {
        int flatc = 0;
        int buldgec = 0;
        const SkScalar rad = SkScalarHalf(fSize.width());
        SkScalar cx = SkScalarHalf(fSize.width());
        SkScalar cy = SkScalarHalf(fSize.height());
        for (int y = 0; y < kILimit; y++) {
            for (int x = 0; x < kILimit; x++) {
                // measure from pixel centers
                SkScalar px = SkIntToScalar(x) + SK_ScalarHalf;
                SkScalar py = SkIntToScalar(y) + SK_ScalarHalf;

                SkPMColor* ptr = fBitmap.getAddr32(x, y);
                SkScalar dist = SkPoint::Length(px - cx, py - cy);
                if (dist <= rad && !*ptr) {
                    flatc++;
                    *ptr = fInsideColor;
                } else if (dist > rad && *ptr) {
                    buldgec++;
                    *ptr = fOutsideColor;
                }
            }
        }
        if (flatCount) *flatCount = flatc;
        if (buldgeCount) *buldgeCount = buldgec;
        return flatc + buldgec;
    }

SkShader* SkPictureShader::refBitmapShader(const SkMatrix& matrix, const SkMatrix* localM) const {
    SkASSERT(fPicture && fPicture->width() > 0 && fPicture->height() > 0);

    SkMatrix m;
    m.setConcat(matrix, this->getLocalMatrix());
    if (localM) {
        m.preConcat(*localM);
    }

    // Use a rotation-invariant scale
    SkPoint scale;
    if (!SkDecomposeUpper2x2(m, NULL, &scale, NULL)) {
        // Decomposition failed, use an approximation.
        scale.set(SkScalarSqrt(m.getScaleX() * m.getScaleX() + m.getSkewX() * m.getSkewX()),
                  SkScalarSqrt(m.getScaleY() * m.getScaleY() + m.getSkewY() * m.getSkewY()));
    }
    SkSize scaledSize = SkSize::Make(scale.x() * fPicture->width(), scale.y() * fPicture->height());

    SkISize tileSize = scaledSize.toRound();
    if (tileSize.isEmpty()) {
        return NULL;
    }

    // The actual scale, compensating for rounding.
    SkSize tileScale = SkSize::Make(SkIntToScalar(tileSize.width()) / fPicture->width(),
                                    SkIntToScalar(tileSize.height()) / fPicture->height());

    SkAutoMutexAcquire ama(fCachedBitmapShaderMutex);

    if (!fCachedBitmapShader || tileScale != fCachedTileScale) {
        SkBitmap bm;
        if (!bm.allocN32Pixels(tileSize.width(), tileSize.height())) {
            return NULL;
        }
        bm.eraseColor(SK_ColorTRANSPARENT);

        SkCanvas canvas(bm);
        canvas.scale(tileScale.width(), tileScale.height());
        canvas.drawPicture(fPicture);

        fCachedTileScale = tileScale;

        SkMatrix shaderMatrix = this->getLocalMatrix();
        shaderMatrix.preScale(1 / tileScale.width(), 1 / tileScale.height());
        fCachedBitmapShader.reset(CreateBitmapShader(bm, fTmx, fTmy, &shaderMatrix));
    }

    // Increment the ref counter inside the mutex to ensure the returned pointer is still valid.
    // Otherwise, the pointer may have been overwritten on a different thread before the object's
    // ref count was incremented.
    fCachedBitmapShader.get()->ref();
    return fCachedBitmapShader;
}

/*
 *  Modulo internal errors, this should always succeed *if* the matrix is downscaling
 *  (in this case, we have the inverse, so it succeeds if fInvMatrix is upscaling)
 */
bool SkDefaultBitmapControllerState::processMediumRequest(const SkBitmapProvider& provider) {
    SkASSERT(fQuality <= kMedium_SkFilterQuality);
    if (fQuality != kMedium_SkFilterQuality) {
        return false;
    }

    // Our default return state is to downgrade the request to Low, w/ or w/o setting fBitmap
    // to a valid bitmap.
    fQuality = kLow_SkFilterQuality;

    SkSize invScaleSize;
    if (!fInvMatrix.decomposeScale(&invScaleSize, nullptr)) {
        return false;
    }

    // Use the largest (non-inverse) scale, to ensure anisotropic consistency.
    SkASSERT(invScaleSize.width() >= 0 && invScaleSize.height() >= 0);
    const SkScalar invScale = SkTMin(invScaleSize.width(), invScaleSize.height());

    if (invScale > SK_Scalar1) {
        fCurrMip.reset(SkMipMapCache::FindAndRef(provider.makeCacheDesc()));
        if (nullptr == fCurrMip.get()) {
            SkBitmap orig;
            if (!provider.asBitmap(&orig)) {
                return false;
            }
            fCurrMip.reset(SkMipMapCache::AddAndRef(orig));
            if (nullptr == fCurrMip.get()) {
                return false;
            }
        }
        // diagnostic for a crasher...
        if (nullptr == fCurrMip->data()) {
            sk_throw();
        }

        SkScalar levelScale = SkScalarInvert(invScale);
        SkMipMap::Level level;
        if (fCurrMip->extractLevel(levelScale, &level)) {
            const SkSize& invScaleFixup = level.fScale;
            fInvMatrix.postScale(invScaleFixup.width(), invScaleFixup.height());

            // todo: if we could wrap the fCurrMip in a pixelref, then we could just install
            //       that here, and not need to explicitly track it ourselves.
            return fResultBitmap.installPixels(level.fPixmap);
        } else {
            // failed to extract, so release the mipmap
            fCurrMip.reset(nullptr);
        }
    }
    return false;
}

static bool check_decompScale(const SkMatrix& matrix) {
    SkSize scale;
    SkMatrix remaining;

    if (!matrix.decomposeScale(&scale, &remaining)) {
        return false;
    }
    if (scale.width() <= 0 || scale.height() <= 0) {
        return false;
    }
    remaining.preScale(scale.width(), scale.height());
    return nearly_equal(matrix, remaining);
}

/*
 *  Modulo internal errors, this should always succeed *if* the matrix is downscaling
 *  (in this case, we have the inverse, so it succeeds if fInvMatrix is upscaling)
 */
bool SkDefaultBitmapControllerState::processMediumRequest(const SkBitmapProvider& provider) {
    SkASSERT(fQuality <= kMedium_SkFilterQuality);
    if (fQuality != kMedium_SkFilterQuality) {
        return false;
    }

    // Our default return state is to downgrade the request to Low, w/ or w/o setting fBitmap
    // to a valid bitmap.
    fQuality = kLow_SkFilterQuality;

    SkSize invScaleSize;
    if (!fInvMatrix.decomposeScale(&invScaleSize, nullptr)) {
        return false;
    }

    SkDestinationSurfaceColorMode colorMode = provider.dstColorSpace()
        ? SkDestinationSurfaceColorMode::kGammaAndColorSpaceAware
        : SkDestinationSurfaceColorMode::kLegacy;
    if (invScaleSize.width() > SK_Scalar1 || invScaleSize.height() > SK_Scalar1) {
        fCurrMip.reset(SkMipMapCache::FindAndRef(provider.makeCacheDesc(), colorMode));
        if (nullptr == fCurrMip.get()) {
            SkBitmap orig;
            if (!provider.asBitmap(&orig)) {
                return false;
            }
            fCurrMip.reset(SkMipMapCache::AddAndRef(orig, colorMode));
            if (nullptr == fCurrMip.get()) {
                return false;
            }
        }
        // diagnostic for a crasher...
        SkASSERT_RELEASE(fCurrMip->data());

        const SkSize scale = SkSize::Make(SkScalarInvert(invScaleSize.width()),
                                          SkScalarInvert(invScaleSize.height()));
        SkMipMap::Level level;
        if (fCurrMip->extractLevel(scale, &level)) {
            const SkSize& invScaleFixup = level.fScale;
            fInvMatrix.postScale(invScaleFixup.width(), invScaleFixup.height());

            // todo: if we could wrap the fCurrMip in a pixelref, then we could just install
            //       that here, and not need to explicitly track it ourselves.
            return fResultBitmap.installPixels(level.fPixmap);
        } else {
            // failed to extract, so release the mipmap
            fCurrMip.reset(nullptr);
        }
    }
    return false;
}

 void draw(SkCanvas* canvas,
           const SkRect& rect,
           const SkSize& deviceSize,
           SkPaint::FilterLevel filterLevel,
           SkImageFilter* input = NULL) {
     SkRect dstRect;
     canvas->getTotalMatrix().mapRect(&dstRect, rect);
     canvas->save();
     SkScalar deviceScaleX = SkScalarDiv(deviceSize.width(), dstRect.width());
     SkScalar deviceScaleY = SkScalarDiv(deviceSize.height(), dstRect.height());
     canvas->translate(rect.x(), rect.y());
     canvas->scale(deviceScaleX, deviceScaleY);
     canvas->translate(-rect.x(), -rect.y());
     SkMatrix matrix;
     matrix.setScale(SkScalarInvert(deviceScaleX),
                     SkScalarInvert(deviceScaleY));
     SkAutoTUnref<SkImageFilter> imageFilter(
         SkMatrixImageFilter::Create(matrix, filterLevel, input));
     SkPaint filteredPaint;
     filteredPaint.setImageFilter(imageFilter.get());
     canvas->saveLayer(&rect, &filteredPaint);
     SkPaint paint;
     paint.setColor(0xFF00FF00);
     SkRect ovalRect = rect;
     ovalRect.inset(SkIntToScalar(4), SkIntToScalar(4));
     canvas->drawOval(ovalRect, paint);
     canvas->restore(); // for saveLayer
     canvas->restore();
 }

static SkVector map_sigma(const SkSize& localSigma, const SkMatrix& ctm) {
    SkVector sigma = SkVector::Make(localSigma.width(), localSigma.height());
    ctm.mapVectors(&sigma, 1);
    sigma.fX = SkMinScalar(SkScalarAbs(sigma.fX), MAX_SIGMA);
    sigma.fY = SkMinScalar(SkScalarAbs(sigma.fY), MAX_SIGMA);
    return sigma;
}

bool SkBitmapController::State::processHighRequest(const SkBitmapProvider& provider) {
    if (fQuality != kHigh_SkFilterQuality) {
        return false;
    }

    fQuality = kMedium_SkFilterQuality;

    SkScalar invScaleX = fInvMatrix.getScaleX();
    SkScalar invScaleY = fInvMatrix.getScaleY();
    if (fInvMatrix.getType() & SkMatrix::kAffine_Mask) {
        SkSize scale;
        if (!fInvMatrix.decomposeScale(&scale)) {
            return false;
        }
        invScaleX = scale.width();
        invScaleY = scale.height();
    }
    invScaleX = SkScalarAbs(invScaleX);
    invScaleY = SkScalarAbs(invScaleY);

    if (invScaleX >= 1 - SK_ScalarNearlyZero || invScaleY >= 1 - SK_ScalarNearlyZero) {
        // we're down-scaling so abort HQ
        return false;
    }

    // Confirmed that we can use HQ (w/ rasterpipeline)
    fQuality = kHigh_SkFilterQuality;
    (void)provider.asBitmap(&fResultBitmap);
    return true;
}

/*
 *  High quality is implemented by performing up-right scale-only filtering and then
 *  using bilerp for any remaining transformations.
 */
bool SkDefaultBitmapControllerState::processHQRequest(const SkBitmap& origBitmap) {
    if (fQuality != kHigh_SkFilterQuality) {
        return false;
    }
    
    // Our default return state is to downgrade the request to Medium, w/ or w/o setting fBitmap
    // to a valid bitmap. If we succeed, we will set this to Low instead.
    fQuality = kMedium_SkFilterQuality;
    
    if (kN32_SkColorType != origBitmap.colorType() || !cache_size_okay(origBitmap, fInvMatrix) ||
        fInvMatrix.hasPerspective())
    {
        return false; // can't handle the reqeust
    }
    
    SkScalar invScaleX = fInvMatrix.getScaleX();
    SkScalar invScaleY = fInvMatrix.getScaleY();
    if (fInvMatrix.getType() & SkMatrix::kAffine_Mask) {
        SkSize scale;
        if (!fInvMatrix.decomposeScale(&scale)) {
            return false;
        }
        invScaleX = scale.width();
        invScaleY = scale.height();
    }
    if (SkScalarNearlyEqual(invScaleX, 1) && SkScalarNearlyEqual(invScaleY, 1)) {
        return false; // no need for HQ
    }
    
    SkScalar trueDestWidth  = origBitmap.width() / invScaleX;
    SkScalar trueDestHeight = origBitmap.height() / invScaleY;
    SkScalar roundedDestWidth = SkScalarRoundToScalar(trueDestWidth);
    SkScalar roundedDestHeight = SkScalarRoundToScalar(trueDestHeight);
    
    if (!SkBitmapCache::Find(origBitmap, roundedDestWidth, roundedDestHeight, &fResultBitmap)) {
        SkAutoPixmapUnlock src;
        if (!origBitmap.requestLock(&src)) {
            return false;
        }
        if (!SkBitmapScaler::Resize(&fResultBitmap, src.pixmap(), SkBitmapScaler::RESIZE_BEST,
                                    roundedDestWidth, roundedDestHeight,
                                    SkResourceCache::GetAllocator())) {
            return false; // we failed to create fScaledBitmap
        }
        
        SkASSERT(fResultBitmap.getPixels());
        fResultBitmap.setImmutable();
        SkBitmapCache::Add(origBitmap, roundedDestWidth, roundedDestHeight, fResultBitmap);
    }
    
    SkASSERT(fResultBitmap.getPixels());
    
    fInvMatrix.postScale(roundedDestWidth / origBitmap.width(),
                         roundedDestHeight / origBitmap.height());
    fQuality = kLow_SkFilterQuality;
    return true;
}

bool SkMipMap::extractLevel(const SkSize& scaleSize, Level* levelPtr) const {
    if (nullptr == fLevels) {
        return false;
    }

    SkASSERT(scaleSize.width() >= 0 && scaleSize.height() >= 0);

#ifndef SK_SUPPORT_LEGACY_ANISOTROPIC_MIPMAP_SCALE
    // Use the smallest scale to match the GPU impl.
    const SkScalar scale = SkTMin(scaleSize.width(), scaleSize.height());
#else
    // Ideally we'd pick the smaller scale, to match Ganesh.  But ignoring one of the
    // scales can produce some atrocious results, so for now we use the geometric mean.
    // (https://bugs.chromium.org/p/skia/issues/detail?id=4863)
    const SkScalar scale = SkScalarSqrt(scaleSize.width() * scaleSize.height());
#endif

    if (scale >= SK_Scalar1 || scale <= 0 || !SkScalarIsFinite(scale)) {
        return false;
    }

    SkScalar L = -SkScalarLog2(scale);
    if (!SkScalarIsFinite(L)) {
        return false;
    }
    SkASSERT(L >= 0);
    int level = SkScalarFloorToInt(L);

    SkASSERT(level >= 0);
    if (level <= 0) {
        return false;
    }

    if (level > fCount) {
        level = fCount;
    }
    if (levelPtr) {
        *levelPtr = fLevels[level - 1];
        // need to augment with our colorspace
        levelPtr->fPixmap.setColorSpace(fCS);
    }
    return true;
}

    void drawBorders(SkCanvas* canvas) {
        SkPaint p;
        p.setStyle(SkPaint::kStroke_Style);
        p.setColor(SK_ColorBLUE);

        SkRect r = SkRect::MakeWH(fCell.width() * 2, fCell.height() * 2);
        r.inset(SK_ScalarHalf, SK_ScalarHalf);
        canvas->drawRect(r, p);
        canvas->drawLine(r.left(), r.centerY(), r.right(), r.centerY(), p);
        canvas->drawLine(r.centerX(), r.top(), r.centerX(), r.bottom(), p);
    }

    void onDrawContent(SkCanvas* canvas) override {
        fCell.set(this->height() / 2, this->height() / 2);

        SkScalar trans[2];
        fTrans.timeToValues(fCurrTime, trans);

        for (int y = 0; y < 2; ++y) {
            for (int x = 0; x < 2; ++x) {
                int index = y * 2 + x;
                SkAutoCanvasRestore acr(canvas, true);
                canvas->translate(fCell.width() * x, fCell.height() * y);
                SkRect r = SkRect::MakeWH(fCell.width(), fCell.height());
                r.inset(4, 4);
                canvas->clipRect(r);
                this->drawHere(canvas, SkFilterQuality(index), trans[0], trans[1]);
            }
        }

        this->drawBorders(canvas);

        const SkScalar textX = fCell.width() * 2 + 30;

        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setTextSize(36);
        SkString str;
        str.appendScalar(fScale);
        canvas->drawText(str.c_str(), str.size(), textX, 100, paint);
        str.reset(); str.appendScalar(fAngle);
        canvas->drawText(str.c_str(), str.size(), textX, 150, paint);

        str.reset(); str.appendScalar(trans[0]);
        canvas->drawText(str.c_str(), str.size(), textX, 200, paint);
        str.reset(); str.appendScalar(trans[1]);
        canvas->drawText(str.c_str(), str.size(), textX, 250, paint);
    }

/*
 *  Modulo internal errors, this should always succeed *if* the matrix is downscaling
 *  (in this case, we have the inverse, so it succeeds if fInvMatrix is upscaling)
 */
bool SkDefaultBitmapControllerState::processMediumRequest(const SkBitmap& origBitmap) {
    SkASSERT(fQuality <= kMedium_SkFilterQuality);
    if (fQuality != kMedium_SkFilterQuality) {
        return false;
    }
    
    // Our default return state is to downgrade the request to Low, w/ or w/o setting fBitmap
    // to a valid bitmap.
    fQuality = kLow_SkFilterQuality;
    
    SkSize invScaleSize;
    if (!fInvMatrix.decomposeScale(&invScaleSize, NULL)) {
        return false;
    }
    SkScalar invScale = SkScalarSqrt(invScaleSize.width() * invScaleSize.height());
    
    if (invScale > SK_Scalar1) {
        fCurrMip.reset(SkMipMapCache::FindAndRef(origBitmap));
        if (NULL == fCurrMip.get()) {
            fCurrMip.reset(SkMipMapCache::AddAndRef(origBitmap));
            if (NULL == fCurrMip.get()) {
                return false;
            }
        }
        // diagnostic for a crasher...
        if (NULL == fCurrMip->data()) {
            sk_throw();
        }
        
        SkScalar levelScale = SkScalarInvert(invScale);
        SkMipMap::Level level;
        if (fCurrMip->extractLevel(levelScale, &level)) {
            SkScalar invScaleFixup = level.fScale;
            fInvMatrix.postScale(invScaleFixup, invScaleFixup);
            
            const SkImageInfo info = origBitmap.info().makeWH(level.fWidth, level.fHeight);
            // todo: if we could wrap the fCurrMip in a pixelref, then we could just install
            //       that here, and not need to explicitly track it ourselves.
            return fResultBitmap.installPixels(info, level.fPixels, level.fRowBytes);
        } else {
            // failed to extract, so release the mipmap
            fCurrMip.reset(NULL);
        }
    }
    return false;
}

// Here is an example of using Skia’s PDF backend (SkPDF) via the SkDocument
// and SkCanvas APIs.
void WritePDF(SkWStream* outputStream,
              const char* documentTitle,
              void (*writePage)(SkCanvas*, int page),
              int numberOfPages,
              SkSize pageSize) {
    SkPDF::Metadata metadata;
    metadata.fTitle = documentTitle;
    metadata.fCreator = "Example WritePDF() Function";
    metadata.fCreation = {0, 2019, 1, 4, 31, 12, 34, 56};
    metadata.fModified = {0, 2019, 1, 4, 31, 12, 34, 56};
    auto pdfDocument = SkPDF::MakeDocument(outputStream, metadata);
    SkASSERT(pdfDocument);
    for (int page = 0; page < numberOfPages; ++page) {
        SkCanvas* pageCanvas = pdfDocument->beginPage(pageSize.width(),
                                                      pageSize.height());
        writePage(pageCanvas, page);
        pdfDocument->endPage();
    }
    pdfDocument->close();
}