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Querying GIS with Animated Spatial Sketches. Presented by Group 4. Querying GIS with Animated Spatial Sketches, Volker Haarslev; Michael Wessel In: Proceedings of the 13th IEEE Symposium on Visual Languages 1997, Sept. 23-26, Capri, Italy, IEEE Press 1997. Overview.
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Querying GIS with Animated Spatial Sketches Presented by Group 4 Querying GIS with Animated Spatial Sketches, Volker Haarslev; Michael Wessel In: Proceedings of the 13th IEEE Symposium on Visual Languages 1997, Sept. 23-26, Capri, Italy, IEEE Press 1997.
Overview • A visual query system VISCO (Vivid Spatial Constellations) for spatial information system is introduced in this paper. • VISCO is domain specific language for spatial information systems or databases, typically geographical information systems (GIS). • It is a sketch-based query language with the support of animation to define a approximate spatial constellations of objects. VISCO uses naive physics metaphor to provide a easy-to-use visual language for users. VISCO provides a way to make query to the Digital Vector Map visually by sketching.
Example • Search for three buildings aligned in parallel.
Evaluation • VISCO has strong metaphor based on naive physical properties of objects and provides high closeness of mapping to GIS. • Very good visibility and low hidden dependencies. The whole query can be represented by a single sketch sheet (WYSIWYG). • Good progressive evaluation: users can refine their query after seeing the result. On the other hand, it is highly unlikely to get the right result at the first place on a very large GIS. It is easy to make mistake, more like a try and error game. • It has terse notation, but with diffuse meaning for the combination of notations. Thus, experience is needed to achieve consistence query result. • Very low viscosity, users can make changes of their query easily by modify the sketch in the graphical query editor.