Unable to take screenshot of Qt3D window with transparent background on Mac

[poortipant]

Hi,

I have an application that renders 3d (dae) files.
I also have a feature on my application - to take screenshots of the current scene.

I am using Qt 5.12 on a Mac 10.14.6

I implemented functionality so that the screenshot could be taken with a transparent
background. This is working fine on Windows, but for some unknown reason it does not make the background transparent on Mac.

This is the code,

Qt3DRender::QRenderCaptureReply m_renderCaptureReply;
...
...
QColor color = QColor(255, 255, 255, 0);
if (color.isValid())
	view->defaultFrameGraph()->setClearColor(color);

m_renderCaptureReply = m_renderCapture->requestCapture();
connect(m_renderCaptureReply, SIGNAL(completed()), this, SLOT(saveImageToFile()));



void My3DQtViewer::saveImageToFile()
{
    QImage image(m_renderCaptureReply->image().size(), QImage::Format_ARGB32);
    image.save(m_screenshotfilename, "PNG");
}

The image is being saved as png but with a white background.

Any ideas what's missing?

Thanks

[SGaist]

Hi,

I can't answer to that directly.

Can you provide a minimal compilable example that shows that behaviour ?