// FIXME: Is it possible to merge getWindowsContext and createWindowsBitmap into a single API
// suitable for all clients?
void GraphicsContext::releaseWindowsContext(HDC hdc, const IntRect& dstRect, bool supportAlphaBlend, bool mayCreateBitmap)
{
bool createdBitmap = mayCreateBitmap && (!m_data->m_hdc || isInTransparencyLayer());
if (!createdBitmap) {
m_data->restore();
return;
}
if (dstRect.isEmpty())
return;
OwnPtr<HBITMAP> bitmap = adoptPtr(static_cast<HBITMAP>(GetCurrentObject(hdc, OBJ_BITMAP)));
DIBPixelData pixelData(bitmap.get());
ASSERT(pixelData.bitsPerPixel() == 32);
CGContextRef bitmapContext = CGBitmapContextCreate(pixelData.buffer(), pixelData.size().width(), pixelData.size().height(), 8,
pixelData.bytesPerRow(), deviceRGBColorSpaceRef(), kCGBitmapByteOrder32Little |
(supportAlphaBlend ? kCGImageAlphaPremultipliedFirst : kCGImageAlphaNoneSkipFirst));
CGImageRef image = CGBitmapContextCreateImage(bitmapContext);
CGContextDrawImage(m_data->m_cgContext.get(), dstRect, image);
// Delete all our junk.
CGImageRelease(image);
CGContextRelease(bitmapContext);
::DeleteDC(hdc);
}
void GraphicsContext::releaseWindowsContext(HDC hdc, const IntRect& dstRect, bool supportAlphaBlend, bool mayCreateBitmap)
{
bool createdBitmap = mayCreateBitmap && (!m_data->m_hdc || isInTransparencyLayer());
if (!hdc || !createdBitmap) {
m_data->restore();
return;
}
if (dstRect.isEmpty())
return;
OwnPtr<HBITMAP> bitmap = adoptPtr(static_cast<HBITMAP>(GetCurrentObject(hdc, OBJ_BITMAP)));
DIBPixelData pixelData(bitmap.get());
ASSERT(pixelData.bitsPerPixel() == 32);
// If this context does not support alpha blending, then it may have
// been drawn with GDI functions which always set the alpha channel
// to zero. We need to manually set the bitmap to be fully opaque.
unsigned char* bytes = reinterpret_cast<unsigned char*>(pixelData.buffer());
if (!supportAlphaBlend)
setRGBABitmapAlpha(bytes, pixelData.size().height() * pixelData.bytesPerRow(), 255);
drawBitmapToContext(m_data, platformContext()->cr(), pixelData, IntSize(dstRect.x(), dstRect.height() + dstRect.y()));
::DeleteDC(hdc);
}
HDC GraphicsContext::getWindowsContext(const IntRect& dstRect, bool supportAlphaBlend, bool mayCreateBitmap)
{
// FIXME: Should a bitmap be created also when a shadow is set?
if (mayCreateBitmap && (!m_data->m_hdc || isInTransparencyLayer())) {
if (dstRect.isEmpty())
return 0;
// Create a bitmap DC in which to draw.
BitmapInfo bitmapInfo = BitmapInfo::create(dstRect.size());
void* pixels = 0;
HBITMAP bitmap = ::CreateDIBSection(NULL, &bitmapInfo, DIB_RGB_COLORS, &pixels, 0, 0);
if (!bitmap)
return 0;
auto bitmapDC = adoptGDIObject(::CreateCompatibleDC(m_data->m_hdc));
::SelectObject(bitmapDC.get(), bitmap);
// Fill our buffer with clear if we're going to alpha blend.
if (supportAlphaBlend)
fillWithClearColor(bitmap);
// Make sure we can do world transforms.
::SetGraphicsMode(bitmapDC.get(), GM_ADVANCED);
// Apply a translation to our context so that the drawing done will be at (0,0) of the bitmap.
XFORM xform = TransformationMatrix().translate(-dstRect.x(), -dstRect.y());
::SetWorldTransform(bitmapDC.get(), &xform);
return bitmapDC.leak();
}
m_data->flush();
m_data->save();
return m_data->m_hdc;
}
