XPLMWorldToLocal
From X-Plane SDK
XPLMWorldToLocal
XPLM_API void XPLMWorldToLocal( double inLatitude, double inLongitude, double inAltitude, double * outX, double * outY, double * outZ);This routine translates coordinates from latitude, longitude, and altitude to local scene coordinates. Latitude and longitude are in decimal degrees, and altitude is in meters MSL (mean sea level). The XYZ coordinates are in meters in the local OpenGL coordinate system.
The altitude for XPLMWorldToLocal is meters MSL (mean sea level). The XYZ coordinates are all in meters in "OpenGL" coordinates - see MovingThePlane for more info.