[geos-devel] Support for M values

Mike Toews mwtoews at gmail.com
Thu Mar 26 18:11:01 PDT 2015

On 27 March 2015 at 01:35, Sandro Santilli <strk at keybit.net> wrote:
> The problem of supporting M is that even 2D geometries will
> grow by 1/4 of each Coordinate, which is a concrete (non-virtual)
> class. I've no idea how would a virtual Coordinate affect performances,
> it would need to be tested.

I've wondered if it is possible to have two kinds of geometry classes:
2D and 4D. A 2D class would implement only 2D logic, and would be
lightweight for the majority of use-cases for GIS work. Then if Z
and/or M support is required, 4D classes could be used, which have
four values per coordinate.

However, I'm not a C++ developer, so I'm not sure if this is possible,
or if there would be any possibility to maintain compatibility.


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