Re: split-window-preferred-function

[martin rudalics]

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>>When the right window is wide enough to be split horizontally, and
>>point is in the left window, what is the best to do here?
>>
>>1. display a buffer in the right window without splitting it;
>>2. split the wide right window horizontally and display a buffer
>>   in a new window;
>>3. split the left window vertically (this option is preferable
>>   for some buffers, e.g. for calendar)
>
>
> By default I'd say the splitting functions only check if the current
> window is wide/high enough.  So I the case above if horizontal splitting
> is preferred and split-width-threshold is more than 40, the horizontal
> splitting function would not be applicable and return nil.  The vertical
> splitting function is the next and checks if the left window is higher
> than split-height-threshold (the default should be changed to something
> like 40).  If it is, then option 3 would be done.  If not, then it would
> return nil, too.  In that case display-buffer would reuse the LRU window
> which is the right one.
>
> I think that's a sensible default.  Users are free to add other
> functions.  For example the splitting functions could be extended to
> search through all windows of the current frame to find one that's large
> enough for a horizontal/vertical split.

Sounds reasonable.  Currently, `display-buffer' searches for the largest
window and tries to split it regardless of which window is selected.  It
usually doesn't because the default value of `split-height-threshold'
prevents splitting.