Thanks for the clarification and news of the up-coming additions. This
issue will not impede me for the moment.
Oh, and by the way - the pragma compile_options sql command is still not
including geopoly in the return list. (using 3.25.3)
Graham
On 18-11-2018 3:57 pm, Richard Hipp wrote:
On 11/17/18, Richard Damon <rich...@damon-family.org> wrote:
On 11/17/18 8:37 PM, Graham Hardman wrote:
My question then is, is it really necessary to ensure a
counterclockwise
order when a polygon shape is entered for the first time in the
table.
My guess would be that SOME operations will need the vertices in the
right order, and others will work regardless of order.
Yeah. For example, the geopoly_area() routine returns a negative
number if the vertexes rotate iCW instead of CCW (which is also a
convenient way to figure out of the order is incorrect). I'm not sure
what other routines malfunction, but I suspect most of them will.
There is a new routine on trunk (and soon to be in 3.26.0) named
geopoly_ccw() that puts the vertexes in the correct CCW order if they
are not already so. This routine was added because I discovered that
many legacy GeoJSON files do not follow the rules and put polygon
vertexes in CW order. I suppose it can also be used after
geopoly_xform() to make sure that the vertexes are in the correct
order there, too.
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