XPLM_API XPLMObjectRef XPLMLoadObject( const char * inPath);
This routine loads an OBJ file and returns a handle to it. If X-plane has already loaded the object, the handle to the existing object is returned. Do not assume you will get the same handle back twice, but do make sure to call unload once for every load to avoid "leaking" objects. The object will be purged from memory when no plugins and no scenery are using it.
The path for the object must be relative to the X-System base folder. If the path is in the root of the X-System folder you may need to prepend ./ to it; loading objects in the root of the X-System folder is STRONGLY discouraged - your plugin should not dump art resources in the root folder!
XPLMLoadObject will return NULL if the object cannot be loaded (either because it is not found or the file is misformatted). This routine will load any object that can be used in the X-Plane scenery system.
It is important that the datarefs an object uses for animation already be loaded before you load the object. For this reason it may be necessary to defer object loading until the sim has fully started.
A known bug: in X-Plane 9.00 this routine requires that the path use /, not : or \. See KnownBugs.