2.5D Clip-Surfaces for Technical Visualization

The concept of clipping planes is well known in computer graphics and can be used to create cut-away views. But clipping against just analytical defined planes is not always suitable for communicating every aspect of such visualization. For example, in hand-drawn technical illustrations, artists tend to communicate the difference between a cut and a model feature by using non-regular, sketchy cut lines instead of straight ones. To enable this functionality in computer graphics, this paper presents a technique for applying 2.5D clip-surfaces in real-time. Therefore, the clip plane equation is extended with an additional offset map, which can be represented by a texture map that contains height values. Clipping is then performed by varying the clip plane equation with respect to such an offset map. Further, a capping technique is proposed that enables the rendering of caps onto the clipped area to convey the impression of solid material. It avoids a re-meshing of a solid polygonal mesh after clipping is performed. Our approach is pixel precise, applicable in real-time, and takes fully advantage of graphics accelerators.

[1]  Takafumi Saito,et al.  Comprehensible rendering of 3-D shapes , 1990, SIGGRAPH.

[2]  Adam Finkelstein,et al.  Adaptive cutaways for comprehensible rendering of polygonal scenes , 2008, SIGGRAPH 2008.

[3]  Eugene Lapidous,et al.  Optimal depth buffer for low-cost graphics hardware , 1999, Workshop on Graphics Hardware.

[4]  Jean-Bernard Martens,et al.  Tangible user interfaces for 3D clipping plane interaction with volumetric data: a case study , 2005, ICMI '05.

[5]  Tobias Isenberg,et al.  Use of Hybrid Rendering Styles for Presentation , 2003, WSCG.

[6]  Jürgen Döllner,et al.  Edge-Enhancement - An Algorithm for Real-Time Non-Photorealistic Rendering , 2003, WSCG.

[7]  David Salesin,et al.  Automated generation of interactive 3D exploded view diagrams , 2008, SIGGRAPH 2008.

[8]  Tom McREYNOLDS,et al.  Programming with OpenGL: Advanced Rendering , 1996 .

[9]  Martin Hachet,et al.  Interactive Generation and Modification of Cutaway Illustrations for Polygonal Models , 2009, Smart Graphics.

[10]  Richard Szeliski,et al.  Layered depth images , 1998, SIGGRAPH.

[11]  William E. Lorensen,et al.  Geometric clipping using Boolean textures , 1993, Proceedings Visualization '93.

[12]  David Salesin,et al.  Interactive cutaway illustrations of complex 3D models , 2007, SIGGRAPH 2007.

[13]  Elaine Cohen,et al.  A non-photorealistic lighting model for automatic technical illustration , 1998, SIGGRAPH.

[14]  Jürgen Döllner,et al.  OpenCSG: A Library for Image-Based CSG Rendering , 2005, USENIX Annual Technical Conference, FREENIX Track.

[15]  Thomas Ertl,et al.  Interactive Clipping Techniques for Texture-Based Volume Visualization and Volume Shading , 2003, IEEE Trans. Vis. Comput. Graph..

[16]  Jürgen Döllner,et al.  Illustrating design and spatial assembly of interactive CSG , 2006, AFRIGRAPH '06.

[17]  Günther Greiner,et al.  Efficient clipping of arbitrary polygons , 1998, TOGS.

[18]  Tobias Höllerer,et al.  Interactive Perspective Cut-away Views for General 3D Scenes , 2006, 3D User Interfaces (3DUI'06).

[19]  Steven K. Feiner,et al.  Computer graphics: principles and practice (2nd ed.) , 1990 .

[20]  Alex T. Pang,et al.  Cutting planes and beyond , 1997, Comput. Graph..

[21]  Wilmot Li,et al.  Exploded View Diagrams of Mathematical Surfaces , 2010, IEEE Transactions on Visualization and Computer Graphics.

[22]  Ivan Viola,et al.  Illustrative Membrane Clipping , 2012, Comput. Graph. Forum.

[23]  Aaron E. Lefohn,et al.  Multi-fragment effects on the GPU using the k-buffer , 2007, SI3D.

[24]  Manuel Menezes de Oliveira Neto,et al.  Real-time relief mapping on arbitrary polygonal surfaces , 2005, I3D '05.

[25]  Oliver Deussen,et al.  Image enhancement by unsharp masking the depth buffer , 2006, SIGGRAPH 2006.

[26]  Tamy Boubekeur,et al.  Generic mesh refinement on GPU , 2005, HWWS '05.

[27]  Cass W. Everitt,et al.  Interactive Order-Independent Transparency , 2001 .

[28]  Dani Lischinski,et al.  Solid texture synthesis from 2D exemplars , 2007, ACM Trans. Graph..

[29]  Thomas Ertl,et al.  Smart Hardware-Accelerated Volume Rendering , 2003, VisSym.

[30]  Thomas Ertl,et al.  Volume clipping via per-fragment operations in texture-based volume visualization , 2002, IEEE Visualization, 2002. VIS 2002..

[31]  Matthias Trapp,et al.  Real-Time Volumetric Tests Using Layered Depth Images , 2008, Eurographics.

[32]  Tony DeRose,et al.  Feature-adaptive GPU rendering of Catmull-Clark subdivision surfaces , 2012, TOGS.