Hi Till, I'm not a "GIS-guy" but I used JTS to do simple geospatial operations (mainly point-in-polygon). I know JTS is under LGPL and their specification AFAIK is mapped to http://geojson.org/geojson-spec.html which under some standard format: https://en.wikipedia.org/wiki/DE-9IM#Standards
On Sun, Aug 9, 2015 at 3:19 AM, Mike Carey <[email protected]> wrote: > I like the proposal that - for the "simple JSON" - everything has a single > string format. > > > On 8/8/15 12:13 AM, Chris Hillery wrote: > >> Ok, sounds like the consensus is that we want to keep circle. That's fine >> with me. To bring the conversation full circle (narf!), now the question >> goes back to how best to represent that type in JSON, given that the >> obvious options don't support it... but, that conversation should continue >> on the original thread. >> >> Thanks! >> Ceej >> aka Chris Hillery >> >> On Fri, Aug 7, 2015 at 10:41 PM, Chen Li <[email protected]> wrote: >> >> I second Ted's argument. The reason on >>> http://forums.mysql.com/read.php?23,148162,152625#msg-152625 is very >>> weak, since following that logic there will be no 100% lines or >>> rectangles on the surface of the earth. But these shapes are very >>> useful. >>> >>> I am sure there are use cases for circles, such as the Apple's new >>> headquarters. A related question is: what's the overhead of >>> implementing and maintaining this type? >>> >>> Chen >>> >>> On Fri, Aug 7, 2015 at 2:04 PM, Ted Dunning <[email protected]> >>> wrote: >>> >>>> There you go. >>>> >>>> Another application. >>>> >>>> >>>> >>>> On Fri, Aug 7, 2015 at 1:43 PM, Mike Carey <[email protected]> wrote: >>>> >>>> AND: What if NASA wants to use us to store its database of crop >>>>> >>>> circles? >>> >>>> :-) >>>>> >>>>> On 8/7/15 11:47 AM, Ted Dunning wrote: >>>>> >>>>> On Fri, Aug 7, 2015 at 3:23 AM, Chris Hillery <[email protected]> >>>>>> wrote: >>>>>> >>>>>> I've noticed that several geospatial serialization formats (at least >>>>>> >>>>>>> "well-known text" and GeoJSON) omit "circle" from their list of basic >>>>>>> geometric forms, even when they have numerous more complex types such >>>>>>> >>>>>> as >>> >>>> multi-curves. This led me to here: >>>>>>> http://forums.mysql.com/read.php?23,148162,152625#msg-152625 >>>>>>> >>>>>>> which offers a reasonably compelling argument for why "circle" is not >>>>>>> >>>>>> a >>> >>>> reasonable shape to discuss in geospatial contexts (loosely, because >>>>>>> there's no consistent way to map that to a spherical coordinate >>>>>>> >>>>>> system). >>> >>>> Actually, that argument is super-weak. It also implies that you >>>>>>> >>>>>> shouldn't >>>>>> have lines (they aren't straight after projection) or squares (they >>>>>> >>>>> aren't >>> >>>> square after projection). But lines and squares both before and after >>>>>> projection are very handy. >>>>>> >>>>>> Circles are useful in many contexts. Drawing the visible horizon for a >>>>>> particular observer is a great example. The flight range of an >>>>>> >>>>> airplane >>> >>>> is >>>>>> another case. Positional error bounds with Gaussian errors is >>>>>> another. >>>>>> >>>>>> Yes. You can approximate it using splines or polygons. But you can >>>>>> approximate anything that way. >>>>>> >>>>>> >>>>>> > -- *Regards,* Wail Alkowaileet
