In virtual environments, terrain is generally modeled by heightfield, a 2D structure. To be able to create desired terrain geometry, software editors for this specific task have been developed. The graphics hardware, data structures and rendering techniques are developing fast to open up new possibilities to the user and terrain editor functionalities are following such improvements (such as real-time lighting updates during editing operations and multi-texture blending). Yet, current terrain editors mostly fail to give the user feedback about their actions and also fail to help the users understand and undo the editing operations on the terrain. The aim of this study is to investigate the 3d-widget based visualization of possible editing (sculpturing) actions on terrain and to help user undo previous operations. © 2009 IEEE.