OpenLayers投影 [英] OpenLayers Projections

问题描述

我可以成功地执行：

  point.transform（new OpenLayers.Projection（EPSG：900913），新的OpenLayers .Projection（ EPSG：4326））; 
  

对于谷歌格式（以米为单位），但是当我想要反向：

  point.transform（new OpenLayers.Projection（EPSG：4326），新的OpenLayers.Projection（EPSG： 900913\" ））; 
  

到一个4326（普通的lat / lon格式）的点，我有一些问题。

当我进行转换时，任何负值似乎都变成NaN（不是数字）。有没有关于转换的东西，我不明白？

编辑：更糟糕的是，当我没有负值时，坐标似乎关闭。我通过在屏幕上绘制一个正方形来获取坐标，然后将这些坐标保存到数据库并稍后加载。我可以在非洲尖端附近画一个正方形（正坐标），然后当它加载它在非洲大陆的顶部附近时，在大西洋。我肯定做错了...

编辑：这是我的代码：

  var navControl = new OpenLayers.Control.Navigation（）; 
 map = new OpenLayers.Map（'map'，{
 
 // restrictedExtent：bounds.clone（），
 
 
}）; 
 //实际绘制地图
 layerMapnik = new OpenLayers.Layer.OSM.Mapnik（Mapnik，{
 displayOutsideMaxExtent：false，
 wrapDateLine：true 
 / / numZoomLevels：10 
}）; 
  

解决方案

啊，我想出了：

在我的代码中有一点，我困惑了经纬度，它把所有的东西都弄乱了。

I can succesfully do:

point.transform(new OpenLayers.Projection("EPSG:900913"), new OpenLayers.Projection("EPSG:4326"));

To a point that is in the google format (in meters), but when I want to do the reverse:

point.transform(new OpenLayers.Projection("EPSG:4326"), new OpenLayers.Projection("EPSG:900913"));

to a point that is in 4326 (regular lat/lon format), I am having some issues.

Any negative value seems to become NaN (not a number) when I do the transformation. Is there something about the transformation in reverse that I don't understand?

Edit: Even worse, when I have no negative values, the coordinates seem off. I am getting the coordinates by drawing a square on the screen, then saving those coordinates to a database and loading them later. I can draw a square near the tip of africa (positive coordinates), and then when it loads it's near the top of africa, in the atlantic ocean. I'm definitely doing something wrong....

Edit: Here's my code: http://pastie.org/911524

Specifically: this is how I initialize my map:

 var navControl = new OpenLayers.Control.Navigation();
                 map = new OpenLayers.Map('map', {

                // restrictedExtent: bounds.clone(),


                 }); 
       //actually draws the map 
        layerMapnik = new OpenLayers.Layer.OSM.Mapnik("Mapnik", {
        displayOutsideMaxExtent: false,
        wrapDateLine: true
        //numZoomLevels: 10
        });

解决方案

Ah, I figured it out:

At one point in my code I confused latitude and longitude it was messing everything up.

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