Worth testing:

#include <CtrlLib/CtrlLib.h>

using namespace Upp;

GUI_APP_MAIN
{
	DDUMP(GetDeviceCaps(GetDC(NULL), SHADEBLENDCAPS) & SB_PIXEL_ALPHA);
}

This should detect whether AlphaBlend is HW accelerated on the platform.... It is 0 on my computer with RX580...

It would also be interesting to test how SW emulation fares, simply by changing

	if(0 && fnAlphaBlend() && IsNull(c) && !ImageFallBack &&

In general, I think it might be a good idea to "reactivate" SetSurface, but maybe we can do that with some Image hinting system? I do not really like the idea of GetKind anymore, it is from old days when 1024x768 bitmap was considered huge...

gtk3: Have you tested:

static Size sz = Ctrl::GetPrimaryScreenArea().GetSize();

?

Mirek