Color BitmapImage::singlePixelSolidColor()
{
// If the image size is not available yet or if the image will be animating don't use the solid color optimization.
if (frameCount() != 1)
return Color();
if (m_solidColor)
return m_solidColor.value();
// If the frame image is not loaded, first use the decoder to get the size of the image.
if (!haveFrameImageAtIndex(0) && m_source.frameSizeAtIndex(0, 0) != IntSize(1, 1)) {
m_solidColor = Color();
return m_solidColor.value();
}
// Cache the frame image. The size will be calculated from the NativeImagePtr.
if (!ensureFrameIsCached(0))
return Color();
ASSERT(m_frames.size());
m_solidColor = NativeImage::singlePixelSolidColor(m_frames[0].m_image.get());
ASSERT(m_solidColor);
return m_solidColor.value();
}
void BitmapImage::checkForSolidColor()
{
m_checkedForSolidColor = true;
m_isSolidColor = false;
if (frameCount() > 1)
return;
if (!haveFrameImageAtIndex(0)) {
IntSize size = m_source.frameSizeAtIndex(0, 0);
if (size.width() != 1 || size.height() != 1)
return;
if (!ensureFrameIsCached(0))
return;
}
CGImageRef image = nullptr;
if (m_frames.size())
image = m_frames[0].m_image.get();
if (!image)
return;
// Currently we only check for solid color in the important special case of a 1x1 image.
if (CGImageGetWidth(image) == 1 && CGImageGetHeight(image) == 1) {
unsigned char pixel[4]; // RGBA
RetainPtr<CGContextRef> bitmapContext = adoptCF(CGBitmapContextCreate(pixel, 1, 1, 8, sizeof(pixel), sRGBColorSpaceRef(),
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big));
if (!bitmapContext)
return;
GraphicsContext(bitmapContext.get()).setCompositeOperation(CompositeCopy);
CGRect destinationRect = CGRectMake(0, 0, 1, 1);
CGContextDrawImage(bitmapContext.get(), destinationRect, image);
if (!pixel[3])
m_solidColor = Color(0, 0, 0, 0);
else
m_solidColor = Color(pixel[0] * 255 / pixel[3], pixel[1] * 255 / pixel[3], pixel[2] * 255 / pixel[3], pixel[3]);
m_isSolidColor = true;
}
}
