Selection and arrangement of graphic elements are two fundamental tasks in many text and graphic editing scenarios. Traditional interactive techniques such as lasso selection, snapping and arrangement commands are provided by most graphic editors to aid the users in accomplishing these tasks. However, these techniques often ignore the underlying patterns of the elements, requiring the users to perform explicit and tedious operations to achieve the goal of the manipulation. It is expected that the amount of user interaction can be reduced by exploiting the patterns of the elements. Nevertheless, designing effective pattern-aware interaction tools is challenging due to the ambiguities in the patterns presented by the elements and the operations issued by the user.

This thesis f...[ Read more ]

Selection and arrangement of graphic elements are two fundamental tasks in many text and graphic editing scenarios. Traditional interactive techniques such as lasso selection, snapping and arrangement commands are provided by most graphic editors to aid the users in accomplishing these tasks. However, these techniques often ignore the underlying patterns of the elements, requiring the users to perform explicit and tedious operations to achieve the goal of the manipulation. It is expected that the amount of user interaction can be reduced by exploiting the patterns of the elements. Nevertheless, designing effective pattern-aware interaction tools is challenging due to the ambiguities in the patterns presented by the elements and the operations issued by the user.

This thesis focuses on developing effective pattern-aware interactive techniques to aid the users in the selection and arrangement of elements. In particular, we propose three interactive techniques which adopt different strategies to resolve the ambiguities that may arise during manipulation.

First, we introduce a selection tool called Lazy Selection. It is a scribble-based tool for quick selection of one or more desired shape elements by roughly stroking through the elements. Our algorithm automatically refines the selection and reveals the user’s intention. It first extracts selection candidates from the scribble-covered elements by examining the underlying patterns and then ranks them based on their location and shape with respect to the user-sketched scribble. Such a design makes this tool tolerant to imprecise input systems and applicable to touch systems without suffering from the fat finger problem.

Second, we present GACA, a group-aware command-based arrangement tool. Compared with the traditional command-based arrangement tools, it reduces the number of selection operations and command invocations. The key idea is that an issued arrangement command is in fact very informative, instructing the tool how to automatically decompose a 2D layout into multiple 1D groups, each one being compatible with the command. The tool uses a parameter-free, command-driven grouping approach so that users can easily predict our grouping results. We also designed a simple user interface to enable explicit control of grouping and arrangement.

Third, we present a framework for automatic global beautification of layouts. To facilitate ambiguity resolution in layout beautification, we include a novel user interface for visualizing and editing inferred relationships. Our interface provides a preview of the beautified layout with inferred constraints, without directly modifying the input layout. In this way, the user can easily keep refining beautification results by interactively repositioning and/or resizing elements in the input layout. In addition, we present a gestural interface for editing automatically inferred constraints by directly interacting with the visualized constraints via simple gestures.