Petr Kristan schrieb:
In the beginning of Grid paint is Canvas.GetClipRect called to obtain area
which wee must redraw. This function directly calls WidgetSet.GetClipBox.
I find out difference betwen Win32 and gtk2 bahaviour of this func.
In gtk2 TGtk2WidgetSet.GetClipBox returns previously Invalidated area
(through DC.PaintRectangle = PS.rcPaint retrieved in BeginPaint)
But in win32 directly calls Windows.GetClipBox, but this func returns
whole grid area. Do not takes account on invalidated area retrieved in
BeginPaint.
It may be a bug in the Win32 widgetset, invalidating the entire control
area instead of only the affected cell, *or* some special handling of
invalidated areas by Windows. I remember that Windows used to extend the
UpdateRect to include *all* invalidated parts of the DC. This can lead
to a big update area, when a single bit at the top left and at the
bottom right of the DC was invalidated. This may have changed in the
meantime, though.
DoDi
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