Hi, Matthias Julius wrote: > IMHO, all those calculations should ideally be done using great > circles.
I agree, but having implemented things like the (initial version of) the "make rectangular" function, which was difficult enough the way it is, I believe it will take a proper mathematician to do this if you want to introduce spherical angle calculations etc. - it is definitely not a matter of simply replacing a few variables here and there. > For most practical purposes using linear approximation with > latlon directly is probably good enough Definitely not. If you make a circle or a square using latlon values, it will only look right within a few degrees of the Equator. > Using Mercator for this might give better results. It does, but then that's what we do now, is it not? > Whatever the model is, I think the same one should be used for all > calculations. Ah, you mean that these calculations should always be based on a Mercator transformation even if you have something else selected. Could probably be done, but would perhaps then require an explanatory note: "You have used the make circle function while using another projection than Mercator. The circle might not look like a real circle on your screen but believe us it is a circle!" ;-) Bye Frederik _______________________________________________ josm-dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/josm-dev
