XPLMSetWindowGeometryVR

XPLMSetWindowGeometryVR

XPLM_API void       XPLMSetWindowGeometryVR(
                         XPLMWindowID         inWindowID,    
                         int                  widthBoxels,    
                         int                  heightBoxels);    

This routine allows you to set the size, in boxels, of a window in VR (that is, a window whose positioning mode is xplm_WindowVR).

Note that you are responsible for ensuring your window is in VR (using XPLMWindowIsInVR()).