[postgis-devel] topology expectations?

[Mike Toews]

On 22 March 2012 05:06, Sandro Santilli <strk at keybit.net> wrote:
> Hey, you have people willing to listen now :)
>
> Would you want to dump some ideas on the recently added page ?
> http://trac.osgeo.org/postgis/wiki/ToleranceDiscussion
>
> Looking forward to you feedback!

One idea to help solve the coordinate robustness issue that has not
been discussed on postgis-devel is to expose the GEOS
PrecisionModel[1] to the C API. Here is some previous discussion on
geos-devel [2].

You can graphically test the PrecisionModel using JTS TestBuilder,
setting Edit > Precision Model at the top menu.

However, if implemented, I'm not sure if or how a user would be able
to modify the precision model for a particular geometry/dataset. I
suppose there could be metadata for topology users to specify a
tolerance, of say 0.001 to snap all coordinates to the nearest
millimeter.

[1] http://geos.refractions.net/ro/doxygen_docs/html/classgeos_1_1geom_1_1PrecisionModel.html
[2] http://old.nabble.com/Change-GEOS-precision-model-td30954848.html

-Mike