map::slippy(3tcl) Mapping utilities map::slippy(3tcl)______________________________________________________________________________NAME
map::slippy - Common code for slippy based map packages
SYNOPSIS
package require Tcl 8.4
package require Tk 8.4
package require map::slippy ?0.2?
::map::slippy length level
::map::slippy tiles level
::map::slippy tile size
::map::slippy tile valid tile levels ?msgvar?
::map::slippy geo 2tile geo
::map::slippy geo 2point geo
::map::slippy tile 2geo tile
::map::slippy tile 2point tile
::map::slippy point 2geo point
::map::slippy point 2tile point
_________________________________________________________________DESCRIPTION
This package provides a number of methods doing things needed by all
types of slippy-based map packages.
API
::map::slippy length level
This method returns the width/height of a slippy-based map at
the specified zoom level, in pixels. This is, in essence, the
result of
expr { [tiles $level] * [tile size] }
::map::slippy tiles level
This method returns the width/height of a slippy-based map at
the specified zoom level, in tiles.
::map::slippy tile size
This method returns the width/height of a tile in a slippy-based
map, in pixels.
::map::slippy tile valid tile levels ?msgvar?
This method checks whether tile described a valid tile in a
slippy-based map containing that many zoom levels. The result is
a boolean value, true if the tile is valid, and false otherwise.
For the latter a message is left in the variable named by msg‐
var, should it be specified.
A tile identifier as stored in tile is a list containing zoom
level, tile row, and tile column, in this order. The command
essentially checks this, i.e. the syntax, that the zoom level is
between 0 and "levels-1", and that the row/col information is
within the boundaries for the zoom level, i.e. 0 ... "[tiles
$zoom]-1".
::map::slippy geo 2tile geo
Converts a geographical location at a zoom level (geo, a list
containing zoom level, latitude, and longitude, in this order)
to a tile identifier (list containing zoom level, row, and col‐
umn) at that level.
::map::slippy geo 2point geo
Converts a geographical location at a zoom level (geo, a list
containing zoom level, latitude, and longitude, in this order)
to a pixel position (list containing zoom level, y, and x) at
that level.
::map::slippy tile 2geo tile
Converts a tile identifier at a zoom level (tile, list contain‐
ing zoom level, row, and column) to a geographical location
(list containing zoom level, latitude, and longitude, in this
order) at that level.
::map::slippy tile 2point tile
Converts a tile identifier at a zoom level (tile, a list con‐
taining zoom level, row, and column, in this order) to a pixel
position (list containing zoom level, y, and x) at that level.
::map::slippy point 2geo point
Converts a pixel position at a zoom level (point, list contain‐
ing zoom level, y, and x) to a geographical location (list con‐
taining zoom level, latitude, and longitude, in this order) at
that level.
::map::slippy point 2tile point
Converts a pixel position at a zoom level (point, a list con‐
taining zoom level, y, and x, in this order) to a tile identi‐
fier (list containing zoom level, row, and column) at that
level.
REFERENCES
[1] http://wiki.openstreetmap.org/wiki/Main_Page
KEYWORDS
geodesy, geography, latitute, location, longitude, map, slippy, zoom
map 0.2 map::slippy(3tcl)
