@INPROCEEDINGS{wjhbgs-rdgtvpc-07,
  author = {Michael Wand and Philipp Jenke and Qi-Xing Huang and Martin Bokeloh and Leonidas Guibas and Andreas Schilling},
  title = {Reconstruction of Deforming Geometry from Time-Varying Point Clouds},
  booktitle = {Proc. Eurographis Symp. on Geometry Processing (SGP) 2007},
  pages = {49--58},
  year = {2007}
}

@INPROCEEDINGS{haw-bsrisaop-07,
  author = {Qi-Xing Huang and Bart Adams and Michael Wand},
  title = {Bayesian Surface Reconstruction via Iterative Scan Alignment to an Optimized Prototype},
  booktitle = {Proc. Eurographis Symp. on Geometry Processing (SGP) 2007},
  year = {2007}
}

@INPROCEEDINGS{jwbss-bpcr-06,
  author = {Philipp Jenke and Michael Wand and Martin Bokeloh and Andreas Schilling and Wolfgang Strasser},
  title = {Bayesian Point Cloud Reconstruction},
  booktitle = {Proc. Eurographics 2006},
  year = {2006},
}

@INPROCEEDINGS{bw-hamrgs-06,
  author = {Martin Bokeloh and Michael Wand},
  title = {Hardware Accelerated Multi-Resolution Geometry Synthesis},
  booktitle = {Proc. Symp. Interactive 3D Graphics and Games},
  year = {2006},
  copyright = {(c) ACM, 2006. This is the author�s version 
   of the work. It is posted here by permission of ACM for
   your personal use. Not for redistribution. The definitive 
   version will be published in the Proceedings of the 
   Symposium on Interactive 3D Graphics
   and Games 2006.},
}

@INPROCEEDINGS{wskw-hamrvr-05,
   AUTHOR = {Wetekam, Gregor and Staneker, Dirk and Kanus, Urs and Wand, Michael},
   TITLE = {A Hardware Architecture for Multi-Resolution Volume Rendering},
   BOOKTITLE = {Proc. of Eurographics/SIGGRAPH Workshop on Graphics Hardware},
   YEAR = {2005},
   KEYWORDS = {Hardware}
}

@INPROCEEDINGS{bfwss-femp-05,
   AUTHOR = {Peter Biber and Sven Fleck and Michael Wand and Dirk Staneker and Wolfgang Stra{\ss}er},
   TITLE = {First Experiences with a Mobile Platform for Flexible 3D Model Acquisition in Indoor and Outdoor Environments -- The W\"{a}gele},
   BOOKTITLE = {3D-ARCH'2005: 3D Virtual Reconstruction and Visualization of Complex Architectures},
   INSTITUTION = {Wilhelm Schickard Institute for Computer Science, Graphical-Interactive Systems (WSI/GRIS), University of T�bingen},
   YEAR = {2005},
   KEYWORDS = {GRIS, W�gele, 3DTV, 3D model acquisition, 3D reconstruction},
   ABSTRACT = {Efficient and comfortable acquisition of large 3D scenes is an important topic for many current and future applications like cultural heritage, web applications and 3DTV and therefore it is a hot research topic. In this paper we present a new mobile 3D model acquisition platform. The platform uses 2D laser range scanners for both self localization by scan matching and geometry acquisition and a digital panorama camera. 3D models are acquired just by moving the platform around. Thereby, geometry is acquired continuously and color images are taken in regular intervals. After matching, the geometry is represented as unstructured point cloud which can then be rendered in several ways, for example using splatting with view dependent texturing. The work presented here is still ?in progress?, but we are able to present some first reconstruction results of indoor and outdoor scenes.}
}

@INPROCEEDINGS{bfbwds-3dmie-05,
   AUTHOR = {Biber,Peter and Fleck,Sven and Busch, Florian and Wand, Michael and Duckett, Tom and Stra{\ss}er, Wolfgang},
   TITLE = {3D Modeling of Indoor Environments by a mobile Platform With a Laser Scanner And Panoramic Camera},
   BOOKTITLE = {13th European Signal Processing Conference (EUSIPCO 2005)},
   MONTH = {September 4-8},
   YEAR = {2005}
}

@PHDTHESIS{w-pbmrr-04,
   AUTHOR = {Michael Wand},
   TITLE = {Point-Based Multi-Resolution Rendering},
   SCHOOL = {Department of computer science and cognitive science, University of T{\"u}bingen}
   INSTITUTION = {Wilhelm Schickard Institute for Computer Science, Graphical-Interactive Systems (WSI/GRIS), University of T{\"u}bingen},
   YEAR = {2004},
   KEYWORDS = {GRIS},
   ABSTRACT = {This thesis describes a new rendering paradigm for handling complex scenes, point-based multi-resolution rendering. The basic idea is to approximate the appearance of complex scenes using a small set of surface sample points. Using hierarchical data structures, the sampling process can be performed in time mostly independent of the scene complexity. This allows an efficient display of highly complex scenes. The thesis proposes different variants of sampling data structures that are useful in different application scenarios, including a variant for handling animated scenes (general keyframe animations). Two different rendering approaches are described: The first approach is a real-time forward mapping algorithm, being a point-based generalization of z-buffer rendering. In contrast to conventional z-buffer rendering, the point-based multi-resolution algorithm can render scenes consisting of trillions of primitives at real-time frame rates while maintaining a comparable rendering quality. The second approach is a backward mapping (i. e. raytracing) algorithm that aims at offline rendering. It is able to compute shadows, reflections, and refractions. It uses a hierarchy of prefiltered sample points to provide efficient antialiasing. Additionally, classic distributed raytracing effects such as soft shadows, depth-of-field, or blurry reflections can be approximated efficiently. In comparison with classic stochastic raytracing techniques, the new algorithm provides noise-free renderings at lower costs than stochastic oversampling for scenes of high variance. The image quality is roughly comparable to that of the classic approach; only a small bias is observed. The thesis provides a theoretical analysis of the sampling and rendering process. Upper bounds for the rendering time are established. For the randomized components of some of the algorithms, analytical lower bounds for the failure probability are derived, showing that arbitrarily high confidence probabilities can be achieved at a small increase of computational costs. An analysis of oversampling properties of different sampling and stratification strategies allows a quantitative comparison, needed to choose the best technique for a certain application. A prototype implementation is presented. The influence of different algorithmic parameters is evaluated empirically and compared to theoretical predictions. Practical applications of the proposed algorithms comprise real-time walkthroughs of highly complex static scenes as well as real-time visualizations of large crowd animations such as a herd of animals or a football stadium with ten thousands of animated football fans. In addition, dynamic modifications of the data structure as needed for interactive editing is examined. Finally, extensions to volume rendering, out-of-core rendering, sound rendering, and simulation of caustics from area light sources are discussed briefly. Overall, the presented techniques extend the possibilities for rendering of highly complex scenes to areas that could not be treated before with comparable efficiency.}
}

@INPROCEEDINGS{ws-mrsr-04,
   AUTHOR = {Michael Wand and Wolfgang Stra{\ss}er},
   TITLE = {Multi-Resolution Sound Rendering},
   BOOKTITLE = {Proc. Symp. Point-Based Graphics 2004},
   YEAR = {2004},
   ABSTRACT = {Point-based multi-resolution representations have been used successfully for rendering highly complex three dimensional scenes in real-time. In this paper, we apply this paradigm to sound rendering: A hierarchy of stochastic sample sound sources is used to approximate complex sound environments (containing a large number of sound sources, such as a football stadium), allowing for interactive real-time walkthroughs. Additionally, the proposed technique can be used for observer-dependent auralizations of simple approximations of global sound propagation. Typical applications of the technique are in virtual reality and computer games, especially to complement established output-sensitive algorithms for rendering visual content.}
}

@ARTICLE{kkfwwm-rst-04,
   AUTHOR = {Jan Klein and Jens Krokowski and Matthias Fischer and Michael Wand and Rolf Wanka and Friedhelm Meyer auf der Heide},
   TITLE = {The Randomized Sample Tree: A Data Structure for Externally Stored Virtual Environments},
   JOURNAL = {Presence},
   VOLUME = {13},
   NUMBER = {6},
   MONTH = December,
   YEAR = {2004}
}

@INPROCEEDINGS{ws-rtc-03,
   AUTHOR = {Michael Wand and Wolfgang Stra{\ss}er},
   TITLE = {Real-Time Caustics},
   EDITOR = {P. Brunet and D. Fellner},
   BOOKTITLE = {Computer Graphics Forum},
   VOLUME = {22(3)},
   YEAR = {2003},
   ABSTRACT = {We present a new algorithm to render caustics. The algorithm discretizes the specular surfaces into sample points. Each of the sample points is treated as a pinhole camera that projects an image of the incoming light onto the diffuse receiver surfaces. Anti-aliasing is performed by considering the local surface curvature at the sample points to filter the projected images. The algorithm can be implemented using programmable texture mapping hardware. It allows to render caustics in fully dynamic scenes in real-time on current PC hardware.}
}

@INPROCEEDINGS{ws-mrpsr-03,
   AUTHOR = {Michael Wand and Wolfgang Stra{\ss}er},
   TITLE = {Multi-Resolution Point-Sample Raytracing},
   BOOKTITLE = {Graphics Interface 2003 Conference Proceedings},
   INSTITUTION = {Wilhelm Schickard Institute for Computer Science, Graphical-Interactive Systems (WSI/GRIS), University of Tübingen},
   YEAR = {2003},
} 

@INPROCEEDINGS{abdws-nahsppr-03,
   AUTHOR = {M. Amor and M. B\'oo and A. del R\'{\i}o and M. Wand and W. Stra{\ss}er},
   TITLE = {A New Algorithm for High-Speed Projection in Point Rendering Applications},
   BOOKTITLE = {DSD-Euromicro Conference. IEEE Computer Society},
   CONFERENCE = {DSD-Euromicro},
   YEAR = {2003},
   KEYWORDS = {Hardware}
}

@TECHREPORT{Wand-2003-ARealTime,
   AUTHOR = {Michael Wand and Wolfgang Stra{\ss}er},
   TITLE = {A Real-Time Sound Rendering Algorithm for Complex Scenes},
   NUMBER = {WSI-2003-5},
   ISSN = {0946-3852},
   INSTITUTION = {Wilhelm Schickard Institute for Computer Science, Graphical-Interactive Systems (WSI/GRIS), University of Tuebingen},
   MONTH = July,
   YEAR = {2003},
   KEYWORDS = {GRIS}
}

	@INPROCEEDINGS{gwgs-irlvds-02,
   AUTHOR = {Stefan Guthe and Michael Wand and Julius Gonser and Wolfgang Stra{\ss}er},
   TITLE = {Interactive Rendering of Large Volume Data Sets},
   BOOKTITLE = {IEEE Visualization 2002},
   YEAR = {2002},
   KEYWORDS = {Visualisation}
}

@ARTICLE{kkfwwm-rst-02,
   AUTHOR = {Jan Klein and Jens Krokowski and Matthias Fischer and Michael Wand and Rolf Wanka and Friedhelm Meyer auf der Heide},
   TITLE = {The Randomized Sample Tree: A Data Structure for Interactive Walkthroughs in Externally Stored Virtual Environments},
   JOURNAL = {Proceedings of ACM Symposium on Virtual Reality Software and Technology (VRST)},
   YEAR = {2002}
}

@ARTICLE{ws-mrrcas-02,
   AUTHOR = {Wand, Michael and Stra{\ss}er, Wolfgang},
   TITLE = {Multi-Resolution Rendering of Complex Animated Scenes},
   JOURNAL = {Computer Graphics Forum},
   VOLUME = {21},
   NUMBER = {3},
   YEAR = {2002},
   NOTE = {Eurographics 2002},
   ABSTRACT = {We present a novel multi-resolution point sample rendering algorithm for keyframe animations. The algorithm accepts triangle meshes of arbitrary topology as input which are animated by specifying different sets of vertices at keyframe positions. A multi-resolution representation consisting of prefiltered point samples and triangles is built to represent the animated mesh at different levels of detail. We introduce a novel sampling and stratification algorithm to efficiently generate suitable point sample sets for moving triangle meshes. Experimental results demonstrate that the new data structure can be used to render highly complex keyframe animations like crowd scenes in real-time.}
}

@INPROCEEDINGS{wfpms-rzb-01,
   AUTHOR = {Michael Wand and Matthias Fischer and Ingmar Peter and Friedhelm Meyer auf der Heide and Wolfgang Stra{\ss}er},
   TITLE = {The Randomized z-Buffer Algorithm: Interactive Rendering of Highly Complex Scenes},
   BOOKTITLE = {SIGGRAPH 2001},
   YEAR = {2001},
   ABSTRACT = {We present a new output-sensitive rendering algorithm, the randomized z-buffer algorithm. It renders an image of an arbitrary three-dimensional scene consisting of triangular primitives by reconstruction from a dynamically chosen set of random surface sample points. This approach is independent of mesh connectivity and topology. The resulting rendering time grows only logarithmically with the numbers of triangles in the scene. We were able to render walkthroughs of scenes of up to 1E14 triangles at interactive frame rates. Automatic identification of low detail scene components ensures that the rendering speed of the randomized z-buffer cannot drop below that of conventional z-buffer rendering. Experimental and analytical evidence is given that the image quality is comparable to that of common approaches like z-buffer rendering. The precomputed data structures employed by the randomized z-buffer allow for interactive dynamic updates of the scene. Their memory requirements grow only linearly with the number of triangles and allow for a scene graph based instantiation scheme to further reduce memory consumption.}
}

@TECHREPORT{wfm-rps-00,
   AUTHOR = {Wand, Michael and Fischer, Matthias and Meyer auf der Heide, Friedhelm},
   TITLE = {Randomized Point Sampling for Output-Sensitive Rendering of Complex Dynamic Scenes},
   NUMBER = {WSI-2000-20},
   ISSN = {0946-3852},
   INSTITUTION = {Wilhelm Schickard Institute for Computer Science, Graphical-Interactive Systems (WSI/GRIS), University of T{\"u}bingen},
   MONTH = November,
   YEAR = {2000},
   KEYWORDS = {I.3.3 [Computer Graphics]: Picture / Image Generation - Display Algorithms; I.3.6 [Computer Graphics]: Methodology and Techniques - Graphics data structures and data types; G.3 [Mathematics of Computing]: Probability and Statistics - Probabilistic algorithms.} ,
   ABSTRACT = {We present a new output-sensitive rendering algorithm, the randomized z-buffer algorithm. It renders an image of a three dimensional scene of triangular primitives by reconstruction from a random sample of surface points which are chosen with a probability proportional to the projected area of the objects. The approach is independent of mesh connectivity and topology. It leads to a rendering time that grows only logarithmically with the numbers of triangles in the scene and to linear memory consumption, thus allowing walkthroughs of scenes of extreme complexity. We consider different methods for image reconstruction which aim at correctness, rendering speed and image quality and we develop an efficient data structure for sample extraction in output-sensitive time which allows for efficient dynamic updates of the scene. Experiments confirm that scenes consisting of some hundred billion triangles can be rendered within seconds with an image quality comparable to a conventional z-buffer rendering; in special cases, realtime performance can be achieved.}
}