javascript 将像素位置转换为纬度/经度，反之亦然
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/7019101/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Convert pixel location to latitude/longitude & vise versa
提问by Tyler Egeto
I need to convert latitude longitude values into pixel positions as well as do the opposite. I've found many solutions to go from lat/lng->pixel, but can't find anything on the reverse.
我需要将纬度经度值转换为像素位置以及做相反的事情。我找到了许多从 lat/lng->pixel 开始的解决方案，但在相反方向上找不到任何解决方案。
A couple of notes:
一些注意事项：
- The map is a fixed size, no zooming, no tiles.
- I don't need anything super accurate, its not important.
- Preferably mercator projection, but not required. I'm not actually display the result. (Any 2D projection)
- I can't rely on any web based API's, ie: no Google Maps
- 地图是固定大小的，没有缩放，没有瓦片。
- 我不需要任何超级准确的东西，这并不重要。
- 最好是墨卡托投影，但不是必需的。我实际上并没有显示结果。（任何二维投影）
- 我不能依赖任何基于网络的 API，即：没有谷歌地图
A solution in almost any programming language would be fine, as long as it doesn't rely on any platform specific APIs.
几乎任何编程语言的解决方案都可以，只要它不依赖于任何特定于平台的 API。
This is an example of going from lat/lng->pixel:
这是一个从 lat/lng->pixel 开始的例子：
var y = Math.round(((-1 * lat) + 90) * (this.MAP_HEIGHT / 180));
var x = Math.round((lng + 180) * (this.MAP_WIDTH / 360));
采纳答案by Markcf
var y = Math.round(((-1 * lat) + 90) * (this.MAP_HEIGHT / 180));
var x = Math.round((lng + 180) * (this.MAP_WIDTH / 360));
Use some algebra and I came out with:
使用一些代数，我得出了：
var lat=(y/(this.MAP_HEIGHT/180)-90)/-1
var lng = x/(this.MAP_WIDTH/360)-180
Not completely confident in that math since it was done in my head, but those should work, just make sure to test them first.
对那个数学不是完全有信心，因为它是在我的脑海中完成的，但那些应该有效，只要确保先测试它们。
