bug#28605: 26.0.60; Part of leftmost character hidden

[martin rudalics]

> OK. The best course of action is then probably not to touch the
> existing adjustments, and not to add any similar ones for the
> horizontal case.

Lars already touched them and IIUC provoked this bug.

>>> That code was added in commit c0055ff5b03c9121ab5bf752496b09416f0f0a7d
>>> which is quite old,
>>
>> ... 2015 rather strikes me as "fairly recent" ...
>>
>
> Oops, I think I looked at the date on the wrong commit, I thought I'd
> seen 2010.

OTOH this means that the code was not tested very intensively and Jan
didn't have much time left to improve it.

>>> I suspect it did no real harm even though oldx
>>> tends to end up negative, possibly x_clear_area does some kind of
>>> clipping.
>>
>> In my experience, X silently swallows anything that happens outside the
>> frame.  GTK can be much more picky in this regard, especially when
>> trying to draw something outside a parent widget.  But the corresponding
>> error messages are usually a pain to read.
>
> Yet another reason not to disturb the status quo.

To be on the safe side, we probably should leave the non-scaling parts
alone.  For the scaling parts do whatever you consider appropriate.  If
it fixes the behavior for Ola, we should install it and wait for
complaints.

martin