T2Viewer

T2Viewer

What is it about

Keywords: Computational Geometry, Dynamic Visualization, Oriented Projective Plane

In order to benefit from the extension of CGAL to the oriented projective plane in the context of the classroom, the need for visualization arose. So, we developed a dynamic visualization system, T²Viewer, which can be seen in action in the videos on this site. T²Viewer can display the planar as well as the spherical models of the Oriented Projective Plane, and allows for interaction with extended CGAL applications, providing means for output display and input generation -- user created elements as well as user selection of objects previously generated by other applications.

T²Viewer was developed in C++, following CGAL's programming guidelines, relies on OpenGL for fast dynamic visualization of the three dimensional models and uses Qt-Designer as its framework. Similar to modifications done to the kernel and the basic_library of CGAL for its extension to the Oriented Projective Plane, the development of T²Viewer required modifications to CGAL's support_library.

Key Benefits

	simultaneous display of both models which allows the viewer the benefit of choosing the most convenient one in each given situation;
	opacity adjustment for either model, allowing for the visualization of one side only, or both at once;
	zoom out and zoom in (all the way to the center of the spherical model -- the origin of the projections);
	broadening and narrowing of the field of view;
	scaling the homogeneous coordinate which permits focusing on details near the origin or on the behavior of objects near infinity;
	some ability to produce algorithm animation.

References

You may read about T²Viewer our Dynamic Visualization System for CGAL's extension to T² in:

This thesis: F. P. Selmi-Dei. Um Visualizador para uma Extensão de CGAL ao Plano Projetivo Orientado. Master's thesis, UNICAMP, 2005.
This short paper: A. G. Oliveira, P. J. de Rezende, F. P. Selmi-Dei. An Extension of CGAL to the Oriented Projective Plane T² and its Dynamic Visualization System. 21st Annual ACM Symp. on Computational Geometry, Pisa, Italy, 2005.

What is available

You may download the source code for the Dynamic Visualization System T²Viewer.

License Terms

Open Source License

T²Viewer is available under an Open Source license. More exactly, it is under the GPL License. If you intend to modify or write your own software based on components of this T²Viewer, make sure you read the GPL license and abide by the terms therein.

Download

The Source code of T²Viewer is available here: README, INSTALL, Source Code=tar.gz

Contact Information

If you have questions not answered in these pages, feel free to contact us. However, we should point out that all the documentation we have available is posted here as well as all the sources we have.

People involved: Fábio P. Selmi-Dei

Pedro J. de Rezende
Electronic mail: General Information:
Postal address: Institute of Computing, UNICAMP, Campinas SP, Brazil
Telephone: +55 19 3521-5860
FAX: +55 19 3521-5847