The emergence of mobile head-mounted displays with robust "inside-out" markerless tracking and video-passthrough permits the creation of novel mixed reality (MR) experiences in which architectural spaces of arbitrary size can be transformed into immersive multi-user visualisation arenas. Here we outline ViewR, an open-source framework for rapidly constructing and deploying architectural-scale multi-user MR experiences. ViewR includes tools for rapid alignment of real and virtual worlds, tracking loss detection and recovery, user trajectory visualisation and world state synchronisation between users with persistence across sessions. ViewR also provides control over the blending of the real and the virtual, specification of site-specific blending zones, and video-passthrough avatars, allowing users to see and interact with one another directly. Using ViewR, we explore the transformation of large architectural structures into immersive arenas by creating a range of experiences in various locations, with a particular focus on architectural affordances such as mezzanines, stairs, gangways and elevators. Our tests reveal that ViewR allows for experiences that would not be possible with pure virtual reality, and indicate that, with certain strategies for recovering from tracking errors, it is possible to construct large scale multi-user MR experiences using contemporary consumer virtual reality head-mounted displays.

In this paper, we present Dynascape, an immersive approach to the composition and playback of dynamic real-world scenes in mixed and virtual reality. We use spatially tracked RGB-D cameras to capture point cloud representations of arbitrary dynamic real-world scenes. Dynascape provides a suite of tools for spatial and temporal editing and composition of such scenes, as well as fine control over their visual appearance. We also explore strategies for spatiotemporal navigation and different tools for the in situ authoring and viewing of mixed and virtual reality scenes. Dynascape is intended as a research platform for exploring the creative potential of dynamic point clouds captured with mobile, tracked RGB-D cameras. We believe our work represents a first attempt to author and playback spatially tracked RGB-D video in an immersive environment, and opens up new possibilities for involving dynamic 3D scenes in virtual space.