void RasterShapeIntervals::appendInterval(int y, int x1, int x2)
{
ASSERT(y >= 0 && y < size() && x1 >= 0 && x2 > x1 && (m_intervalLists[y].isEmpty() || x1 > m_intervalLists[y].last().x2()));
m_bounds.unite(IntRect(x1, y, x2 - x1, 1));
m_intervalLists[y].append(IntShapeInterval(x1, x2));
}
bool RasterShapeIntervals::contains(const IntRect& rect) const
{
if (!bounds().contains(rect))
return false;
const IntShapeInterval& rectInterval = IntShapeInterval(rect.x(), rect.maxX());
for (int y = rect.y(); y < rect.maxY(); y++) {
if (!shapeIntervalsContain(intervalsAt(y), rectInterval))
return false;
}
return true;
}
PassOwnPtr<Shape> Shape::createRasterShape(Image* image, float threshold, const LayoutRect& imageR, const LayoutRect& marginR, WritingMode writingMode, float margin)
{
IntRect imageRect = pixelSnappedIntRect(imageR);
IntRect marginRect = pixelSnappedIntRect(marginR);
OwnPtr<RasterShapeIntervals> intervals = adoptPtr(new RasterShapeIntervals(marginRect.height(), -marginRect.y()));
OwnPtr<ImageBuffer> imageBuffer = ImageBuffer::create(imageRect.size());
if (image && imageBuffer) {
// FIXME: This is not totally correct but it is needed to prevent shapes
// that loads SVG Images during paint invalidations to mark layoutObjects for
// layout, which is not allowed. See https://crbug.com/429346
ImageObserverDisabler disabler(image);
SkPaint paint;
IntRect imageSourceRect(IntPoint(), image->size());
IntRect imageDestRect(IntPoint(), imageRect.size());
image->draw(imageBuffer->canvas(), paint, imageDestRect, imageSourceRect, DoNotRespectImageOrientation, Image::DoNotClampImageToSourceRect);
WTF::ArrayBufferContents contents;
imageBuffer->getImageData(Unmultiplied, IntRect(IntPoint(), imageRect.size()), contents);
RefPtr<DOMArrayBuffer> arrayBuffer = DOMArrayBuffer::create(contents);
RefPtr<DOMUint8ClampedArray> pixelArray = DOMUint8ClampedArray::create(arrayBuffer, 0, arrayBuffer->byteLength());
unsigned pixelArrayOffset = 3; // Each pixel is four bytes: RGBA.
uint8_t alphaPixelThreshold = threshold * 255;
ASSERT(static_cast<unsigned>(imageRect.width() * imageRect.height() * 4) == pixelArray->length());
int minBufferY = std::max(0, marginRect.y() - imageRect.y());
int maxBufferY = std::min(imageRect.height(), marginRect.maxY() - imageRect.y());
for (int y = minBufferY; y < maxBufferY; ++y) {
int startX = -1;
for (int x = 0; x < imageRect.width(); ++x, pixelArrayOffset += 4) {
uint8_t alpha = pixelArray->item(pixelArrayOffset);
bool alphaAboveThreshold = alpha > alphaPixelThreshold;
if (startX == -1 && alphaAboveThreshold) {
startX = x;
} else if (startX != -1 && (!alphaAboveThreshold || x == imageRect.width() - 1)) {
int endX = alphaAboveThreshold ? x + 1 : x;
intervals->intervalAt(y + imageRect.y()).unite(IntShapeInterval(startX + imageRect.x(), endX + imageRect.x()));
startX = -1;
}
}
}
}
OwnPtr<RasterShape> rasterShape = adoptPtr(new RasterShape(intervals.release(), marginRect.size()));
rasterShape->m_writingMode = writingMode;
rasterShape->m_margin = margin;
return rasterShape.release();
}
std::unique_ptr<Shape> Shape::createRasterShape(Image* image, float threshold, const LayoutRect& imageR, const LayoutRect& marginR, WritingMode writingMode, float margin)
{
IntRect imageRect = pixelSnappedIntRect(imageR);
IntRect marginRect = pixelSnappedIntRect(marginR);
auto intervals = std::make_unique<RasterShapeIntervals>(marginRect.height(), -marginRect.y());
std::unique_ptr<ImageBuffer> imageBuffer = ImageBuffer::create(imageRect.size());
if (imageBuffer) {
GraphicsContext* graphicsContext = imageBuffer->context();
graphicsContext->drawImage(image, ColorSpaceDeviceRGB, IntRect(IntPoint(), imageRect.size()));
RefPtr<Uint8ClampedArray> pixelArray = imageBuffer->getUnmultipliedImageData(IntRect(IntPoint(), imageRect.size()));
unsigned pixelArrayLength = pixelArray->length();
unsigned pixelArrayOffset = 3; // Each pixel is four bytes: RGBA.
uint8_t alphaPixelThreshold = threshold * 255;
int minBufferY = std::max(0, marginRect.y() - imageRect.y());
int maxBufferY = std::min(imageRect.height(), marginRect.maxY() - imageRect.y());
if (static_cast<unsigned>(imageRect.width() * imageRect.height() * 4) == pixelArrayLength) {
for (int y = minBufferY; y < maxBufferY; ++y) {
int startX = -1;
for (int x = 0; x < imageRect.width(); ++x, pixelArrayOffset += 4) {
uint8_t alpha = pixelArray->item(pixelArrayOffset);
bool alphaAboveThreshold = alpha > alphaPixelThreshold;
if (startX == -1 && alphaAboveThreshold) {
startX = x;
} else if (startX != -1 && (!alphaAboveThreshold || x == imageRect.width() - 1)) {
// We're creating "end-point exclusive" intervals here. The value of an interval's x1 is
// the first index of an above-threshold pixel for y, and the value of x2 is 1+ the index
// of the last above-threshold pixel.
int endX = alphaAboveThreshold ? x + 1 : x;
intervals->intervalAt(y + imageRect.y()).unite(IntShapeInterval(startX + imageRect.x(), endX + imageRect.x()));
startX = -1;
}
}
}
}
}
auto rasterShape = std::make_unique<RasterShape>(WTF::move(intervals), marginRect.size());
rasterShape->m_writingMode = writingMode;
rasterShape->m_margin = margin;
return WTF::move(rasterShape);
}
IntShapeInterval MarginIntervalGenerator::intervalAt(int y) const
{
unsigned xInterceptsIndex = abs(y - m_y);
int dx = (xInterceptsIndex >= m_xIntercepts.size()) ? 0 : m_xIntercepts[xInterceptsIndex];
return IntShapeInterval(m_x1 - dx, m_x2 + dx);
}
void RasterShapeIntervals::appendInterval(int y, int x1, int x2)
{
ASSERT(x2 > x1 && (intervalsAt(y).isEmpty() || x1 > intervalsAt(y).last().x2()));
m_bounds.unite(IntRect(x1, y, x2 - x1, 1));
intervalsAt(y).append(IntShapeInterval(x1, x2));
}
