void PDFDocumentImage::updateCachedImageIfNeeded(GraphicsContext* context, const FloatRect& dstRect, const FloatRect& srcRect)
{
// If we have an existing image, reuse it if we're doing a low-quality paint, even if cache parameters don't match;
// we'll rerender when we do the subsequent high-quality paint.
InterpolationQuality interpolationQuality = context->imageInterpolationQuality();
bool useLowQualityInterpolation = interpolationQuality == InterpolationNone || interpolationQuality == InterpolationLow;
if (!m_cachedImageBuffer || (!cacheParametersMatch(context, dstRect, srcRect) && !useLowQualityInterpolation)) {
m_cachedImageBuffer = context->createCompatibleBuffer(enclosingIntRect(dstRect).size());
if (!m_cachedImageBuffer)
return;
GraphicsContext* bufferContext = m_cachedImageBuffer->context();
if (!bufferContext) {
m_cachedImageBuffer = nullptr;
return;
}
transformContextForPainting(bufferContext, dstRect, srcRect);
drawPDFPage(bufferContext);
m_cachedTransform = context->getCTM(GraphicsContext::DefinitelyIncludeDeviceScale);
m_cachedDestinationSize = dstRect.size();
m_cachedSourceRect = srcRect;
IntSize internalSize = m_cachedImageBuffer->internalSize();
size_t oldCachedBytes = m_cachedBytes;
m_cachedBytes = internalSize.width() * internalSize.height() * 4;
if (imageObserver())
imageObserver()->decodedSizeChanged(this, safeCast<int>(m_cachedBytes) - safeCast<int>(oldCachedBytes));
}
}
void PDFDocumentImage::updateCachedImageIfNeeded(GraphicsContext& context, const FloatRect& dstRect, const FloatRect& srcRect)
{
#if PLATFORM(IOS)
// On iOS, if the physical memory is less than 1GB, do not allocate more than 16MB for the PDF cachedImage.
const size_t memoryThreshold = WTF::GB;
const size_t maxArea = 16 * WTF::MB / 4; // 16 MB maximum size, divided by a rough cost of 4 bytes per pixel of area.
if (ramSize() <= memoryThreshold && ImageBuffer::compatibleBufferSize(dstRect.size(), context).area() >= maxArea) {
m_cachedImageBuffer = nullptr;
return;
}
// On iOS, some clients use low-quality image interpolation always, which throws off this optimization,
// as we never get the subsequent high-quality paint. Since live resize is rare on iOS, disable the optimization.
// FIXME (136593): It's also possible to do the wrong thing here if CSS specifies low-quality interpolation via the "image-rendering"
// property, on all platforms. We should only do this optimization if we're actually in a ImageQualityController live resize,
// and are guaranteed to do a high-quality paint later.
bool repaintIfNecessary = true;
#else
// If we have an existing image, reuse it if we're doing a low-quality paint, even if cache parameters don't match;
// we'll rerender when we do the subsequent high-quality paint.
InterpolationQuality interpolationQuality = context.imageInterpolationQuality();
bool repaintIfNecessary = interpolationQuality != InterpolationNone && interpolationQuality != InterpolationLow;
#endif
if (m_cachedImageBuffer && (!repaintIfNecessary || cacheParametersMatch(context, dstRect, srcRect)))
return;
m_cachedImageBuffer = ImageBuffer::createCompatibleBuffer(FloatRect(enclosingIntRect(dstRect)).size(), context);
if (!m_cachedImageBuffer)
return;
auto& bufferContext = m_cachedImageBuffer->context();
transformContextForPainting(bufferContext, dstRect, srcRect);
drawPDFPage(bufferContext);
m_cachedTransform = context.getCTM(GraphicsContext::DefinitelyIncludeDeviceScale);
m_cachedDestinationSize = dstRect.size();
m_cachedSourceRect = srcRect;
IntSize internalSize = m_cachedImageBuffer->internalSize();
size_t oldCachedBytes = m_cachedBytes;
m_cachedBytes = safeCast<size_t>(internalSize.width()) * internalSize.height() * 4;
if (imageObserver())
imageObserver()->decodedSizeChanged(this, safeCast<int>(m_cachedBytes) - safeCast<int>(oldCachedBytes));
}
void PDFDocumentImage::draw(GraphicsContext& context, const FloatRect& dstRect, const FloatRect& srcRect, CompositeOperator op, BlendMode, ImageOrientationDescription)
{
if (!m_document || !m_hasPage)
return;
updateCachedImageIfNeeded(context, dstRect, srcRect);
{
GraphicsContextStateSaver stateSaver(context);
context.setCompositeOperation(op);
if (m_cachedImageBuffer)
context.drawImageBuffer(*m_cachedImageBuffer, dstRect);
else {
transformContextForPainting(context, dstRect, srcRect);
drawPDFPage(context);
}
}
if (imageObserver())
imageObserver()->didDraw(this);
}