Undo/Redo operations in Bitmap-based Collaborative Graphic Editing Systems
Real-time collaborative graphic editors allow a group of users to view and edit the same graphic document at the same time from geographically dispersed sites connected by communication networks.Bitmap-based graphic editing systems are special collaborative editing systems,and Undo/Redo operations are intricate problems in this field.Existing solutions add extra space,thus showing low efficiency of the algorithms.In this paper,based on Multi-version strategy,we propose a new solution to solve the Undo/Redo consistency problem,and consider three possible cases: all-causal,all-independent and causal-independent-mixed operations.In addition,compared with previous collaborative algorithms,the algorithm proposed in this paper supports selective Un-do,without requiring additional space and the implementation of Undo/Redo is more flexible.
Real-time Collaboration Bitmap-based document model Graphic Editing System Multi-version Strategy Undo/Redo Selective Undo
Liping Gao Fangyu Yu Qiongqiong Fu Yuben Zhang Shanshan Wang Naixue Xiong
School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai,P.R China
国际会议
南昌
英文
1-13
2013-09-26（万方平台首次上网日期，不代表论文的发表时间）