[postgis-devel] Looking for a good ST_ChangeEdgeGeom semantic

[Andrea Peri]

Perhaps an acceptable simplification should be
allow a edge change that don't change the
id of leftface and rightface as available on the edges.

This mean to allow a change of edge geometry only if the result is always
between the same two faces.

This mean also that it could move to another set of start/end nodes but
only if always inside the same two faces.
But see-ing the iso specs is no really clear to me if the start-node and
the end_node  must be always the same or can change.

So for example:

If the starting situation was this:  (were 'o' are node not vertex)

    o--------------o
    |              |
    o------E1------o
    |              |
    |              |
    |              |
    o              o
    |              |
    |              |
    |              |
    o--------------o


this other should be allowed with a ST_ChangeEdgeGeom ?

    o--------------o
    |              |
    o              o
    |              |
    |              |
    |              |
    o-----E1-------o
    |              |
    |              |
    |              |
    o--------------o


It will leave the same two faces for the edge E1.

or not?

I guess no.


-- 
-----------------
Andrea Peri
. . . . . . . . .
qwerty àèìòù
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