361354 - Consider not using get_inner_gdk_window to determine drag target widget

Status: NEW

(Core :: Widget: Gtk, enhancement)

Description

[Boris Zbarsky [:bzbarsky]]

Right now, the code in nsWindow::OnDragMotionEvent (gtk2 version) does:

2317     returnWindow = get_inner_gdk_window(thisWindow, aX, aY,
2318                                         &retx, &rety);
2319     nsWindow *innerMostWidget = NULL;
2320     innerMostWidget = get_window_for_gdk_window(returnWindow);
2321 
2322     if (!innerMostWidget)
2323         innerMostWidget = this;

The call to get_window_for_gdk_window takes up quite some profile time and more importantly hits the X server over and over getting widget geometries.

Wouldn't it make more sense to walk our child tree and thus determine which widget the point falls in?