> Notice that change_frame_size takes lines/columns as arguments, not
> pixels, so windows can only be sized in those increments.
Right. And the proposal of the others boils down to make these pixel
arguments instead. All I tried to explain was that doing that is fairly
easy because we don't have to bother about the tool and menubars any
more.
The harder part is to handle converse routines like getting the right
window from coordinates or `pos-visible-in-window-p'. For those we
probably have to store pixel sizes within the window structure to avoid
recalculating sizes, for example, during mouse tracking. And storing
pixel sizes means we have to update them whenever we resize windows or
the minibuffer.