The geography bits of TileStache.
 
A Projection defines the relationship between the rendered tiles and the
underlying geographic data. Generally, just one popular projection is used
for most web maps, "spherical mercator".
 
Built-in projections:
- spherical mercator
- WGS84
 
Example use projection in a layer definition:
 
    "layer-name": {
        "projection": "spherical mercator",
        ...
    }
 
You can define your own projection, with a module and object name as arguments:
 
    "layer-name": {
        ...
        "projection": "Module:Object"
    }
 
The object must include methods that convert between coordinates, points, and
locations. See the included mercator and WGS84 implementations for example.
You can also instantiate a projection class using this syntax:
 
    "layer-name": {
        ...
        "projection": "Module:Object()"
    }

Modules
		TileStache.Core

Classes
		ModestMaps.Geo.LinearProjection(ModestMaps.Geo.IProjection) WGS84 ModestMaps.Geo.MercatorProjection(ModestMaps.Geo.IProjection) SphericalMercator   class SphericalMercator(ModestMaps.Geo.MercatorProjection)     Spherical mercator projection for most commonly-used web map tile scheme.   This projection is identified by the name "spherical mercator" in the TileStache config. The simplified projection used here is described in greater detail at: http://trac.openlayers.org/wiki/SphericalMercator     Method resolution order: SphericalMercator ModestMaps.Geo.MercatorProjection ModestMaps.Geo.IProjection Methods defined here: __init__(self) coordinateProj(self, coord) Convert from Coordinate object to a Point object in EPSG:900913 locationProj(self, location) Convert from Location object to a Point object in EPSG:900913 projCoordinate(self, point) Convert from Point object in EPSG:900913 to a Coordinate object projLocation(self, point) Convert from Point object in EPSG:900913 to a Location object Data and other attributes defined here: srs = '+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lo...0 +units=m +nadgrids=@null +wktext +no_defs +over' Methods inherited from ModestMaps.Geo.MercatorProjection: rawProject(self, point) rawUnproject(self, point) Methods inherited from ModestMaps.Geo.IProjection: coordinateLocation(self, coordinate) locationCoordinate(self, location) project(self, point) unproject(self, point)   class WGS84(ModestMaps.Geo.LinearProjection)     Unprojected projection for the other commonly-used web map tile scheme.   This projection is identified by the name "WGS84" in the TileStache config.     Method resolution order: WGS84 ModestMaps.Geo.LinearProjection ModestMaps.Geo.IProjection Methods defined here: __init__(self) coordinateProj(self, coord) Convert from Coordinate object to a Point object in EPSG:4326 locationProj(self, location) Convert from Location object to a Point object in EPSG:4326 projCoordinate(self, point) Convert from Point object in EPSG:4326 to a Coordinate object projLocation(self, point) Convert from Point object in EPSG:4326 to a Location object Data and other attributes defined here: srs = '+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs' Methods inherited from ModestMaps.Geo.LinearProjection: rawProject(self, point) rawUnproject(self, point) Methods inherited from ModestMaps.Geo.IProjection: coordinateLocation(self, coordinate) locationCoordinate(self, location) project(self, point) unproject(self, point)

Functions
		getProjectionByName(name) Retrieve a projection object by name.   Raise an exception if the name doesn't work out.