No projection warnings.

This commit is contained in:
Tim Schaub
2012-06-19 15:43:09 +02:00
parent efcecc4c5f
commit 6f3b47709a
2 changed files with 248 additions and 26 deletions

View File

@@ -1,34 +1,261 @@
goog.provide('ol.Projection');
/**
* @constructor
* @param {string} code Projection identifier.
*/
ol.Projection = function() {
ol.Projection = function(code) {
/**
* @private
* @type {string}
*/
this.code_ = code;
/**
* @private
* @type {string|undefined}
*/
this.code_ = undefined;
this.units_ = undefined;
/**
* @private
* @type {Object|undefined}
*/
this.proj_ = undefined;
};
/**
* @return {string|undefined} Code.
* @return {string} Code.
*/
ol.Projection.prototype.getCode = function() {
return this.code_;
};
/**
* @param {string|undefined} code Code.
* @param {string} code Code.
* @return {ol.Projection} This.
*/
ol.Projection.prototype.setCode = function(code) {
this.code_ = code;
return this;
};
/**
* @export
* @param {string=} opt_code Code.
* @return {ol.Projection|string} Result.
*/
ol.Projection.prototype.code = function(opt_code){
if (goog.isDef(opt_code)) {
return this.setCode(opt_code);
}
else {
return this.getCode();
}
};
/**
* @return {string|undefined} Code.
*/
ol.Projection.prototype.getUnits = function() {
return this.units_;
};
/**
* @param {string|undefined} units Units abbreviation.
* @return {ol.Projection} This.
*/
ol.Projection.prototype.setUnits = function(units) {
this.units_ = units;
return this;
};
/**
* @export
* @param {string=} opt_units Units abbreviation.
* @return {undefined|ol.Projection|string} Result.
*/
ol.Projection.prototype.units = function(opt_units){
if (goog.isDef(opt_units)) {
return this.setUnits(opt_units);
}
else {
return this.getUnits();
}
};
/**
* Transforms is an object, with from properties, each of which may
* have a to property. This allows you to define projections without
* requiring support for proj4js to be included.
*
* This object has keys which correspond to a 'source' projection object. The
* keys should be strings, corresponding to the projection.getCode() value.
* Each source projection object should have a set of destination projection
* keys included in the object.
*
* Each value in the destination object should be a transformation function,
* where the function is expected to be passed an object with a .x and a .y
* property. The function should return the object, with the .x and .y
* transformed according to the transformation function.
*
* Note - Properties on this object should not be set directly. To add a
* transform method to this object, use the <addTransform> method. For an
* example of usage, see the OpenLayers.Layer.SphericalMercator file.
*
* @type {Object}
*/
ol.Projection.transforms = {};
/**
* APIProperty: defaults
* {Object} Defaults for the SRS codes known to OpenLayers (currently
* EPSG:4326, CRS:84, urn:ogc:def:crs:EPSG:6.6:4326, EPSG:900913, EPSG:3857,
* EPSG:102113 and EPSG:102100). Keys are the SRS code, values are units,
* maxExtent (the validity extent for the SRS) and yx (true if this SRS is
* known to have a reverse axis order).
*/
ol.Projection.defaults = {
"EPSG:4326": {
units: "degrees",
maxExtent: [-180, -90, 180, 90],
yx: true
},
"CRS:84": {
units: "degrees",
maxExtent: [-180, -90, 180, 90]
},
"EPSG:900913": {
units: "m",
maxExtent: [-20037508.34, -20037508.34, 20037508.34, 20037508.34]
}
};
/**
* APIMethod: addTransform
* Set a custom transform method between two projections. Use this method in
* cases where the proj4js lib is not available or where custom projections
* need to be handled.
*
* Parameters:
* from - {String} The code for the source projection
* to - {String} the code for the destination projection
* method - {Function} A function that takes a point as an argument and
* transforms that point from the source to the destination projection
* in place. The original point should be modified.
*/
ol.Projection.addTransform = function(from, to, method) {
if (method === ol.Projection.nullTransform) {
var defaults = ol.Projection.defaults[from];
if (defaults && !ol.Projection.defaults[to]) {
ol.Projection.defaults[to] = defaults;
}
}
if(!ol.Projection.transforms[from]) {
ol.Projection.transforms[from] = {};
}
ol.Projection.transforms[from][to] = method;
};
/**
* Transform a point coordinate from one projection to another.
*
* @param {Object} point Object with x and y properties.
* @param {!string|!ol.Projection} source Source projection.
* @param {!string|!ol.Projection} dest Destination projection.
* @returns {Object} Object with x and y properties.
*/
ol.Projection.transform = function(point, source, dest) {
if (!(source instanceof ol.Projection)) {
source = new ol.Projection(source);
}
if (!(dest instanceof ol.Projection)) {
dest = new ol.Projection(dest);
}
if (source.proj_ && dest.proj_) {
// point = Proj4js.transform(source.proj, dest.proj, point);
} else {
var sourceCode = source.getCode();
var destCode = dest.getCode();
var transforms = ol.Projection.transforms;
if (transforms[sourceCode] && transforms[sourceCode][destCode]) {
transforms[sourceCode][destCode](point);
}
}
return point;
};
/**
* APIFunction: nullTransform
* A null transformation - useful for defining projection aliases when
* proj4js is not available:
*
* (code)
* ol.Projection.addTransform("EPSG:3857", "EPSG:900913",
* ol.Projection.nullTransform);
* ol.Projection.addTransform("EPSG:900913", "EPSG:3857",
* ol.Projection.nullTransform);
* (end)
*/
ol.Projection.nullTransform = function(point) {
return point;
};
/**
* Note: Transforms for web mercator <-> geographic
* OpenLayers recognizes EPSG:3857, EPSG:900913, EPSG:102113 and EPSG:102100.
* OpenLayers originally started referring to EPSG:900913 as web mercator.
* The EPSG has declared EPSG:3857 to be web mercator.
* ArcGIS 10 recognizes the EPSG:3857, EPSG:102113, and EPSG:102100 as
* equivalent. See http://blogs.esri.com/Dev/blogs/arcgisserver/archive/2009/11/20/ArcGIS-Online-moving-to-Google-_2F00_-Bing-tiling-scheme_3A00_-What-does-this-mean-for-you_3F00_.aspx#12084.
* For geographic, OpenLayers recognizes EPSG:4326, CRS:84 and
* urn:ogc:def:crs:EPSG:6.6:4326. OpenLayers also knows about the reverse axis
* order for EPSG:4326.
*/
(function() {
var pole = 20037508.34;
function inverseMercator(xy) {
xy.x = 180 * xy.x / pole;
xy.y = 180 / Math.PI * (2 * Math.atan(Math.exp((xy.y / pole) * Math.PI)) - Math.PI / 2);
return xy;
}
function forwardMercator(xy) {
xy.x = xy.x * pole / 180;
xy.y = Math.log(Math.tan((90 + xy.y) * Math.PI / 360)) / Math.PI * pole;
return xy;
}
function map(base, codes) {
var add = ol.Projection.addTransform;
var same = ol.Projection.nullTransform;
var i, len, code, other, j;
for (i=0, len=codes.length; i<len; ++i) {
code = codes[i];
add(base, code, forwardMercator);
add(code, base, inverseMercator);
for (j=i+1; j<len; ++j) {
other = codes[j];
add(code, other, same);
add(other, code, same);
}
}
}
// list of equivalent codes for web mercator
var mercator = ["EPSG:900913", "EPSG:3857", "EPSG:102113", "EPSG:102100"],
geographic = ["CRS:84", "urn:ogc:def:crs:EPSG:6.6:4326", "EPSG:4326"],
i;
for (i=mercator.length-1; i>=0; --i) {
map(mercator[i], geographic);
}
for (i=geographic.length-1; i>=0; --i) {
map(geographic[i], mercator);
}
})();