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#leaflet-baidu: This plugin in no longer maintained nor enchanced#

An on-going plugin for leaflet with Baidu Map.

##Why this plugin?## Baidu map is using a different coordinate system and a different algorithm to calculate tile coordinate. Inspired by another leaflet plugin by Pavel Shramov and Bruno B. It is dedicated for Google, Bing, and Yandex map.

##Contributing to the code## I have created several tickets in the issue list with "help wanted" labels. If you have any idea, please do not hesitate leave a comment or make a pull request. All advices are appreciated.
It would be great if you create the branch accordingly: fix_number of issue.
It would also be great if you create commit message accordingly: re #number of issue: your commit message

##How Does Baidu Map Work?## Basically, there are 4 kinds of coordinate need to know: Longitude and Latitude, point coordinate, pixel coordiante, tile coordinate. In the following demostration, I will use the coordinate of Tian'an Men(116.404, 39.915) in Baidu coordinate system.

###Longitude and Latitude### The coordinate Baidu Map using is different from WGS84, which is general international standards. One layer encryption is required by the Chinese goverment, which is called GCJ-02. Moreover, Baidu Map encrypts another layer called BD-09 based on GCJ-02. Here's an interface to convert those coordinates.

###Point Coordinate### Baidu Map uses Mercator projection. The difference between Baidu Map and other maps in projection is the range of latitude. Google map will project the earth to a square, latitude is roughly from -85 to 85; whereas baidu map projects the earth from -71.988531 to 74.000022. This coordinate convertion is managed by a class called BMap from Baidu.

var projection = new BMap.MercatorProjection();
var point = projection.lngLatToPoint(new BMap.Point(116.404, 39.915));
alert(point.x + ", " + point.y);
//results: 12958175, 4825923.77

An image to show point coordinate:

###Pixel Coordinate### Formula: pixel_coordinate = |point_coordinate * 2^(zoom-18)|. If you how to make math equation in markdown feel free to make a pull request.
18 is the Max Zoom level of Baidu map. The pixel coordinate of Tian'an Men in Zoom Level 4 in Baidu Map is 790, 294.

###Tile Coordinate### Formula: tile_coordinate = |pixel_coordinate/256|
256 is the size of the tile height and width in Baidu Map. For instance, the tile coordinate of Tian'an Men in zoom level 4 is 3,1, and 50617, 18851 in zoom level 18.

###Chinese Documentation### The coordinate system is cited from Here. Here's more details in Chinese.

##Contact## My email is [email protected]. Again, all advices are appreciated.