Mpd Comments and Questions
- I'd prefer "crs" to "srs", the latter being out step with, for example, EPSG and OGC terminology. Ditto for "LineString" and "Line", and perhaps (although less so) "Envelope" and "Box"
- Why reference PROJ.4's EPSG tables and not the EPSG tables themselves? Do I sense a coordinate order holy war type thing going on?
- What about Multi[Point|LineString|Polygon] and GeometryCollection?
- What about Polygons with multiple rings? An earlier proposal handled this.
- How does a client determine whether the, for example, six ordinates in a Line/LineString are two x,y,z-s or three x,y-s?
- You suggested an "Authors" section, for CC reasons. Care to add one?
- Shoot. I thought SRS was in vogue and CRS is out. Great. Let's go with crs. I have no preference with linestring, etc.
- PROJ vs EPSG. PROJ is what coders will see. They may never look at EPSG. Few people will use anything other than PROJ.
- Multi Schmulti, I always say. :)
- Rings Schmings... toss 'em in.
- This is JSON, not GML, so we should (a) use commas and (b) use proper arrays and arrays of arrays.
- Drat. OK. Authors coming right up.
Mpd Response to response
- I don't understand: do you mean use PROJ.4 definition strings? How about OGC URN-s (with click-through licence)? Examples are: "urn:ogc:def:crs:OGC:1.3:CRS84" for the CRS formerly known as "EPSG:4326 with lat/lon axes order"; and "urn:ogc:def:crs:EPSG:6.3:26986" for "EPSG:26986".
- MultiPolygons and MultiLines really do exist.
- Anyone for Quoits?
- OK by me
- Clearly this system of commenting on the comments is going to break down soon.
- I mean literally taken from the file called 'epsg' which on my system installs into /Library/Frameworks/PROJ.framework/Versions/Current/Resources/proj/epsg. It looks sort of like this:
# Unknown datum based upon the Airy 1830 ellipsoid <4001> +proj=longlat +ellps=airy +no_defs <> # Unknown datum based upon the Airy Modified 1849 ellipsoid <4002> +proj=longlat +a=6377340.189 +b=6356034.447938534 +no_defs <> # Unknown datum based upon the Australian National Spheroid <4003> +proj=longlat +ellps=aust_SA +no_defs <>
From that, the codes I mean are the ones in < >. There might be a better way to phrase this rule... But it boils down to not requiring people to find, read, and understand the EPSG tables themselves.
- I believe you, let's add them. In fact, why not just say we'll allow geometries that have OGC WKT definitions. There must be a list somewhere.
- If there's an OGC WKT, Quoits are in.
- . Great.
- You're welcome. (See, the numbering broke, and I don't have the wiki-fu to fix it).