BlenderVR is an open-source project framework for interactive and immersive applications based on an extension of the Blender Game Engine to Virtual Reality applications. BlenderVR is a generalization of the BlenderCAVE project, accounting for alternate platforms (e.g., HMD, video-walls). The goal is to provide a flexible and easy to use framework for the creation of VR applications for various platforms, making use of the existing power of the BGE's graphics rendering and physics engine. Compatible with 3 major Operating Systems, BlenderVR has been developed by VR researchers with support from the Blender Community. BlenderVR currently handles multi-screen/multi-user tracked stereoscopic rendering through efficient low-level master/slave synchronization process with multimodal interactions via OSC and VRPN protocols.

6DoF navigation in a virtual world can usually be implemented by two types of navigation techniques: joystick-based input devices and steering metaphors based on movements of the user's body, e.g. head-controlled paradigms. These two different types of 6DoF navigation techniques provide users with the same level of control, but the latter introduces the user's physical movements in the navigation, which we believe will improve the navigation experience in immersive virtual environments. In this paper, we compare these two types of 6DoF navigation techniques in an immersive context, through an experiment using both objective and subjective measurements to assess user performance, the occurrence of cybersickness symptoms and the level of presence, when using either of these navigation paradigms.

Many applications using Virtual Reality (VR) require free hand navigation control. This forbids the use of devices such as Joystick, 3D mouse, ... That is generally because hand-based gesture interaction must be dedicated to specific tasks: sculpting or grasping the objects, which compose a virtual scene. With this aim, we present a polyvalent display approach, which allows the system to determine the desired focus and the moving intention of the user for virtual navigations. After we point out the limits of the classical solutions used to control virtual navigations, we describe the conceptual and mathematical implementation of our approach. Some of our considerations depend on physiological and ergonomic constraints. We conclude on the first applications of our fully head tracking navigation controller.