openlayers
Version:
Build tools and sources for developing OpenLayers based mapping applications
33 lines (27 loc) • 762 B
JavaScript
goog.provide('ol.proj.Units');
goog.require('ol.sphere.NORMAL');
/**
* Projection units: `'degrees'`, `'ft'`, `'m'`, `'pixels'`, `'tile-pixels'` or
* `'us-ft'`.
* @enum {string}
*/
ol.proj.Units = {
DEGREES: 'degrees',
FEET: 'ft',
METERS: 'm',
PIXELS: 'pixels',
TILE_PIXELS: 'tile-pixels',
USFEET: 'us-ft'
};
/**
* Meters per unit lookup table.
* @const
* @type {Object.<ol.proj.Units, number>}
* @api stable
*/
ol.proj.Units.METERS_PER_UNIT = {};
ol.proj.Units.METERS_PER_UNIT[ol.proj.Units.DEGREES] =
2 * Math.PI * ol.sphere.NORMAL.radius / 360;
ol.proj.Units.METERS_PER_UNIT[ol.proj.Units.FEET] = 0.3048;
ol.proj.Units.METERS_PER_UNIT[ol.proj.Units.METERS] = 1;
ol.proj.Units.METERS_PER_UNIT[ol.proj.Units.USFEET] = 1200 / 3937;