void FEOffset::apply(Filter* filter)
{
m_in->apply(filter);
if (!m_in->resultImage())
return;
GraphicsContext* filterContext = getEffectContext();
if (!filterContext)
return;
setIsAlphaImage(m_in->isAlphaImage());
FloatRect sourceImageRect = filter->sourceImageRect();
sourceImageRect.scale(filter->filterResolution().width(), filter->filterResolution().height());
if (filter->effectBoundingBoxMode()) {
m_dx *= sourceImageRect.width();
m_dy *= sourceImageRect.height();
}
m_dx *= filter->filterResolution().width();
m_dy *= filter->filterResolution().height();
FloatRect dstRect = FloatRect(m_dx + m_in->scaledSubRegion().x() - scaledSubRegion().x(),
m_dy + m_in->scaledSubRegion().y() - scaledSubRegion().y(),
m_in->scaledSubRegion().width(),
m_in->scaledSubRegion().height());
filterContext->drawImageBuffer(m_in->resultImage(), DeviceColorSpace, dstRect);
}
GraphicsContext* FilterEffect::getEffectContext()
{
IntRect bufferRect = enclosingIntRect(scaledSubRegion());
m_effectBuffer = ImageBuffer::create(bufferRect.size(), LinearRGB);
return m_effectBuffer->context();
}
FloatRect FilterEffect::calculateDrawingRect(const FloatRect& srcRect)
{
FloatPoint startPoint = FloatPoint(srcRect.x() - scaledSubRegion().x(), srcRect.y() - scaledSubRegion().y());
FloatRect drawingRect = FloatRect(startPoint, srcRect.size());
return drawingRect;
}
IntRect FilterEffect::calculateDrawingIntRect(const FloatRect& effectRect)
{
IntPoint location = roundedIntPoint(FloatPoint(scaledSubRegion().x() - effectRect.x(),
scaledSubRegion().y() - effectRect.y()));
return IntRect(location, resultImage()->size());
}