perdrix
3rd July 2020, 11:25
In the OnMouseMove() mf of a Win32 custom control which I am re-writing for Qt, there is some code that looks like this:
//----- Get the original erase area -----//
getMarkerRgn(&oldrgn);
//----- Draw the markers -----//
:
:
getMarkerRgn(&newrgn);
erasergn.CreateRectRgn(0,0,0,0); //Dummy rgn
erasergn.CombineRgn(&oldrgn, &newrgn, RGN_DIFF);
dc.FillRgn(&erasergn, &brush); // Background colour brush
The idea being to erase the previously drawn markers after the new ones are drawn
What should I be doing in Qt?
PS is there any Qt equivalent of the Windows OnEraseBackGround() ?
PPS only three weeks Qt experience so far so please be gentle!
Many thanks
David
//----- Get the original erase area -----//
getMarkerRgn(&oldrgn);
//----- Draw the markers -----//
:
:
getMarkerRgn(&newrgn);
erasergn.CreateRectRgn(0,0,0,0); //Dummy rgn
erasergn.CombineRgn(&oldrgn, &newrgn, RGN_DIFF);
dc.FillRgn(&erasergn, &brush); // Background colour brush
The idea being to erase the previously drawn markers after the new ones are drawn
What should I be doing in Qt?
PS is there any Qt equivalent of the Windows OnEraseBackGround() ?
PPS only three weeks Qt experience so far so please be gentle!
Many thanks
David