information about object types

README.md

@@ -11,6 +11,7 @@ Tile38 is an open source (MIT licensed), in-memory geolocation data store, spati
 - Spatial index with [search](#searching) methods such as Nearby, Within, and Intersects.
 - Realtime [geofencing](#geofencing).
 - Variety of client protocols, including [http](#http) (curl), [websockets](#websockets), [telnet](#telnet), and a [native interface](#native-interface).
+- Multiple object types including [lat/lon point](#latlon-point), [bounding box](#bounding-box), [Geohash](#geohash), [GeoJSON](#geojson), [QuadKey](#quadkey), and [XYZ tile](#xyz-tile).
 - Server responses are in json.
 - Full [command line interface](#cli).
 - Leader / follower [replication](#replication).
@@ -160,6 +161,50 @@ The `detect` may be `enter | exit | cross`.
 - `exit` is when an object that **was** previously in the fence has exited the area.
 - `cross` is when an object that **was not** previously in the fence has entered and exited the area.
 
+## Object types
+
+All object types except for XYZ Tiles and QuadKeys can be stored in a collection. XYZ Tiles and QuadKeys are reserved for the SEARCH keyword only.
+
+### Lat/lon point
+The most basic object type is a point that is composed of a latitude and a longitude. There is an optional `z` member that may be used for auxilary data such as elevation or a timestamp.
+```
+set fleet truck1 point 33.5123 -112.2693     # plain lat/lon
+set fleet truck1 point 33.5123 -112.2693 225 # lat/lon with z member
+```
+
+### Bounding box
+A bounding box consists of two points. The first being the southwestern most point and the second is the northeastern most point.
+```
+set fleet truck1 bounds 30 -110 40 -100
+```
+### Geohash
+A [geohash](https://en.wikipedia.org/wiki/Geohash) is a string respresentation of a point. With the length of the string indicating the precision of the point. 
+```
+set fleet truck1 hash 9tbnthxzr # this would be equivlent to 'point 33.5123 -112.2693'
+```
+
+### GeoJSON
+[GeoJSON](http://geojson.org/) is an industry standard format for representing a variety of object types including a point, multipoint, linestring, multilinestring, polygon, multipolygon, geometrycollection, feature, and featurecollection. Tile38 supports all of the standards with these exceptions.
+
+1. The `crs` member is not supported and will be ignored. The CRS84/WGS84 projection is assumed.
+2. Any member that is not recognized (including `crs`) will be ignored.
+3. All coordinates can be 2 or 3 axes. Less than 2 axes or more than 3 will result in a parsing error.
+
+<i>* All ignored members will not persist.</i>
+
+**Important to note that all coordinates are in Longitude, Latitude order.**
+
+```
+set city tempe object {"type":"Polygon","coordinates":[[[0,0],[10,10],[10,0],[0,0]]]}
+```
+
+### XYZ Tile
+An XYZ tile is rectangle bounding area on earth that is represented by an X, Y coordinate and a Z (zoom) level.
+Check out [maptiler.org](http://www.maptiler.org/google-maps-coordinates-tile-bounds-projection/) for an interactive example.
+
+### QuadKey Tile
+A QuadKey used the same coordinate system as an XYZ tile except that the string representation is a string characters composed of 0, 1, 2, or 3. For a detailed explanation checkout [The Bing Maps Tile System](https://msdn.microsoft.com/en-us/library/bb259689.aspx).
+
 
 ## Network protocols