CoWebDraw: a real-time collaborative graphical editing system supporting multi-clients based on HTML5

Real-time collaborative graphical editing system allows a group of users simultaneously to view and edit the shared graphical documents from geographically dispersed sites connected by networks. The strategy of consistency maintenance is the key technique to ensure correctness in this editing system. This paper maps the two-dimensional drawing area into the linear structure in the real-time collaborative graphical editing system in the Web environment, and transforms the two-dimensional graphical operations to the linear operations. Based on the above, this paper improves the ABST algorithm to be suitable for this new environment. In order to verify the correctness and feasibility of the algorithm, this paper develops the real-time collaborative graphical editing system CoWebDraw based on Web, which adopts the HTML5 WebSocket protocol to achieve the real-time transformation of the information. In this system, geographically dispersed users can edit the shared graphical documents through web browsers. In the mobile internet era, the CoWebDraw system supports the concurrent editing of the same documents by multi-clients.