Real-time online interaction is the norm today. Tabletops and other dedicated interactive surface devices with direct input and tangible interaction can enhance remote collaboration, and open up new interaction scenarios based on mixed physical/virtual components. However, they are only available to a small subset of users, as they usually require identical bespoke hardware for every participant, are complex to setup, and need custom scenario-specific applications.

We present SurfaceCast, a software toolkit designed to merge multiple distributed, heterogeneous end-user devices into a single, shared mixed-reality surface. Supported devices include regular desktop and laptop computers, tablets, and mixed-reality headsets, as well as projector-camera setups and dedicated interactive tabletop systems.
This device-agnostic approach provides a fundamental building block for exploration of a far wider range of usage scenarios than previously feasible, including future clients using our provided API.

In this paper, we discuss the software architecture of SurfaceCast, present a formative user study and a quantitative performance analysis of our framework, and introduce five example application scenarios which we enhance through the multi-user and multi-device features of the framework.
Our results show that the hardware- and content-agnostic architecture of SurfaceCast can run on a wide variety of devices with sufficient performance and fidelity for real-time interaction.