ST_WrapX

[strk]

Still looking for a good name, anyway the idea is to allow people to "split" a set of geometries in a table so that every component falling off a given X-value is X-shifted by a given amount. Tipical use is to make a wgs84 map visible as 0,360 rather than -180,180 or as whatever makes sense of a specific use (think pacific).

This was referred to as ST_ShiftLongitude on the mailing list  http://postgis.refractions.net/pipermail/postgis-devel/2010-February/008886.html

But the "Longitude" part is misleading as it may be useful in mercator too for example..

[strk]

longitudeWrap version

[strk]

I think ST_HWrap is a good name. Now we have a name, half work is done :)

[strk]

HWrap I still didn't like as it assumes X is horizontal. So it's now called ST_WrapX. The attached version also makes use of the new ST_Split function and calls ST_Union as the last step.

Now it seems a pretty good and complete function to let down to C.