2.1虚拟地球坐标系。
分为地理坐标系(经纬高)和笛卡尔坐标系(x,y,z)
一般跨度度数,经度【-180,180】,纬度[-90,90]
经纬度也可以按照弧度度量,转换方式如下:
![](https://img-blog.csdnimg.cn/20210215194828704.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
![](https://img-blog.csdnimg.cn/2021021519495747.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
分为三维Geodetic3D(经纬高),
Geodetic2D(经纬度)表示表面
![](https://img-blog.csdnimg.cn/20210215195156456.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
![](https://img-blog.csdnimg.cn/2021021519524843.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
用法如下:
![](https://img-blog.csdnimg.cn/20210215195452661.png)
![](https://img-blog.csdnimg.cn/2021021519560317.png)
2.1.2wgs84坐标系。
在opengl渲染时,不能用经纬高,所以要转换成x,y,z,比如wgs84坐标系,单位是米,用double型。另外,地理坐标系中的高度也用double类型的米。
wgs84坐标系中,原点位于地球质点,x轴指向地理坐标系中的(0,0,),y轴指向(90,0),z轴指向北极点。赤道位于xy平面内。右手坐标系。x X y=z
笛卡尔坐标用Vector3Dl类表示。比如
![](https://img-blog.csdnimg.cn/20210215201140832.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
![](https://img-blog.csdnimg.cn/20210215201227368.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
![](https://img-blog.csdnimg.cn/20210215201314643.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)
![](https://img-blog.csdnimg.cn/20210215201416244.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2RpcmVjdHgzZF9iZWdpbm5lcg==,size_16,color_FFFFFF,t_70)