public void cairo_transform_to_window (Context cr, Widget widget, Window window)
Transforms the given cairo context
cr that from
widget-relative coordinates to
widget’s window is not an ancestor of
window, no modification will be applied.
This is the inverse to the transformation GTK applies when preparing an expose event to be emitted with the draw signal. It is intended to help porting multiwindow widgets from GTK+ 2 to the rendering architecture of GTK+ 3.
the cairo context to transform
the widget the context is currently centered for
the window to transform the context to