In order for HAR to become widely accepted, the users must be able to create AR contents by positioning virtual objects in the real environment [7,8]. Furthermore, the potential HAR users want to create AR contents in various indoor and outdoor environments [9]. The basic 3D manipulation [10] of virtual objects is fundamental in HAR content creation and 3D positioning is the first subtask of virtual object manipulation.
HAR systems often utilize AR markers to track the environment, but the use of markers can be impractical or restricted in many use environments. Markerless tracking technologies, such as SLAM, track the environment without the need for adding any physical objects to the environment. In order to enable the 3D positioning of virtual objects, the markerless tracking based HAR system needs to reconstruct a 3D map of the environment. However, due to the insufficient processing capabilities of modern handheld devices and the vast amount of possible use environments, the correct 3D mapping of the environment might not