Re: Gets vertical skylines from grob stencils (issue 5626052)

[David Kastrup]

"address@hidden" <address@hidden> writes:

> Hey all,
>
> I've uploaded a first-pass attempt at implementing the suggestion that
> Joe talked about (using buildings directly in the skylines).
> This saves a lot of time in the calculation of skyline distance (time
> spent in Axis_group_interface::skyline_spacing can go from 2 to 0.2
> seconds for scores with lots of beams and hairpins).
>
> However, the global time takes a huge hike with this patchset because
> skylines are constantly being rebuilt with padding added on.

It would appear to me that one would want to implement padding
operations working on whole readily-built skylines.  That should be more
efficient than padding the individual elements.

I would consider it perfectly tenable if we needed to rethink our
padding specifications to better work in the context of full skyline
interaction.  So if a particular kind of padding hack we implemented in
the context of rectangular skylines does not map well to more accurate
skylines, it is perfectly valid to replace it by different padding kinds
that are a better match to what we actually do.  For example, some
horizontal skyline padding was designed to prevent excessive
interlocking.  If the skylines are no longer rectilinear, strictly
horizontal padding makes only very limited sense.

-- 
David Kastrup