On 8/17/10 7:14 PM, Phil Scadden wrote: > >> How do you know that the line (179 0, -179 0) is meant to cross the date >> line? >> > You cant as far as I know. And how would you unambiguously specify it?
Please don't try to bake in any assumptions about heading in a line segment. Our geometry model is based on coordinates on a plane. My opinion is that "crossing the dateline" is application logic. Geometries should be split when the user tries to draw beyond the domain of the coordinate system. > We generally store everything in arcSDE in WGS84 lat/long and depend on > client mapping to sort it out. When you have no unambiguous way of > specify which way the line goes, the obvious convention is take the > shortest distance. ship track/air track are overwhelming source of data > in this catagory while I cant really think of a mapping application > where you would want 179,0, -179,0 to be circle the globe. -- Tim Schaub OpenGeo - http://opengeo.org Expert service straight from the developers. _______________________________________________ Dev mailing list Dev@openlayers.org http://openlayers.org/mailman/listinfo/dev