@article{SemmoTrappKyprianidisetal.2012,
  author    = {Semmo, Amir and Trapp, Matthias and Kyprianidis, Jan Eric and D{\"o}llner, J{\"u}rgen Roland Friedrich},
  title     = {Interactive visualization of generalized virtual 3D city models using level-of-abstraction transitions},
  series = {Computer graphics forum : journal of the European Association for Computer Graphics},
  volume    = {31},
  journal   = {Computer graphics forum : journal of the European Association for Computer Graphics},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0167-7055},
  doi       = {10.1111/j.1467-8659.2012.03081.x},
  pages     = {885 -- 894},
  year      = {2012},
  abstract  = {Virtual 3D city models play an important role in the communication of complex geospatial information in a growing number of applications, such as urban planning, navigation, tourist information, and disaster management. In general, homogeneous graphic styles are used for visualization. For instance, photorealism is suitable for detailed presentations, and non-photorealism or abstract stylization is used to facilitate guidance of a viewer's gaze to prioritized information. However, to adapt visualization to different contexts and contents and to support saliency-guided visualization based on user interaction or dynamically changing thematic information, a combination of different graphic styles is necessary. Design and implementation of such combined graphic styles pose a number of challenges, specifically from the perspective of real-time 3D visualization. In this paper, the authors present a concept and an implementation of a system that enables different presentation styles, their seamless integration within a single view, and parametrized transitions between them, which are defined according to tasks, camera view, and image resolution. The paper outlines potential usage scenarios and application fields together with a performance evaluation of the implementation.},
  language  = {en}
}
@article{SemmoHildebrandtTrappetal.2012,
  author    = {Semmo, Amir and Hildebrandt, Dieter and Trapp, Matthias and D{\"o}llner, J{\"u}rgen Roland Friedrich},
  title     = {Concepts for cartography-oriented visualization of virtual 3D city models},
  series = {Photogrammetrie, Fernerkundung, Geoinformation},
  journal   = {Photogrammetrie, Fernerkundung, Geoinformation},
  number    = {4},
  publisher = {Schweizerbart},
  address   = {Stuttgart},
  issn      = {1432-8364},
  doi       = {10.1127/1432-8364/2012/0131},
  pages     = {455 -- 465},
  year      = {2012},
  abstract  = {Virtual 3D city models serve as an effective medium with manifold applications in geoinformation systems and services. To date, most 3D city models are visualized using photorealistic graphics. But an effective communication of geoinformation significantly depends on how important information is designed and cognitively processed in the given application context. One possibility to visually emphasize important information is based on non-photorealistic rendering, which comprehends artistic depiction styles and is characterized by its expressiveness and communication aspects. However, a direct application of non-photorealistic rendering techniques primarily results in monotonic visualization that lacks cartographic design aspects. In this work, we present concepts for cartography-oriented visualization of virtual 3D city models. These are based on coupling non-photorealistic rendering techniques and semantics-based information for a user, context, and media-dependent representation of thematic information. This work highlights challenges for cartography-oriented visualization of 3D geovirtual environments, presents stylization techniques and discusses their applications and ideas for a standardized visualization. In particular, the presented concepts enable a real-time and dynamic visualization of thematic geoinformation.},
  language  = {en}
}