7 results
Search Results
Now showing 1 - 7 of 7
Item Real-Time Shape Editing using Radial Basis Functions(The Eurographics Association and Blackwell Publishing, Inc, 2005) Botsch, Mario; Kobbelt, LeifItem Young Researcher Award 2007(The Eurographics Association and Blackwell Publishing Ltd, 2007) Botsch, MarioItem An Interactive Approach to Point Cloud Triangulation(Blackwell Publishers Ltd and the Eurographics Association, 2000) Kobbelt, Leif P.; Botsch, MarioWe present an interactive system for the generation of high quality triangle meshes that allows us to handle hybrid geometry (point clouds, polygons,. . .) as input data. In order to be able to robustly process huge data sets, we exploit graphics hardware features like the raster manager and the z-buffer for specific sub-tasks in the overall procedure. By this we significantly accelerate the stitching of mesh patches and obtain an algorithm for sub-sampling the data points in linear time. The target resolution and the triangle alignment in sub-regions of the resulting mesh can be controlled by adjusting the screen resolution and viewing transformation. An intuitive user interface provides a flexible tool for application dependent optimization of the mesh.Item Resampling Feature and Blend Regions in Polygonal Meshes for Surface Anti-Aliasing(Blackwell Publishers Ltd and the Eurographics Association, 2001) Botsch, Mario; Kobbelt, LeifEfficient surface reconstruction and reverse engineering techniques are usually based on a polygonal mesh representation of the geometry: the resulting models emerge from piecewise linear interpolation of a set of sample points. The quality of the reconstruction not only depends on the number and density of the sample points but also on their alignment to sharp and rounded features of the original geometry. Bad alignment can lead to severe alias artifacts. In this paper we present a sampling pattern for feature and blend regions which minimizes these alias errors. We show how to improve the quality of a given polygonal mesh model by resampling its feature and blend regions within an interactive framework. We further demonstrate sophisticated modeling operations that can be implemented based on this resampling technique.Item Multiresolution Surface Representation Based on Displacement Volumes(Blackwell Publishers, Inc and the Eurographics Association, 2003) Botsch, Mario; Kobbelt, LeifWe propose a new representation for multiresolution models which uses volume elements enclosed between thedifferent resolution levels to encode the detail information. Keeping these displacement volumes locally constantduring a deformation of the base surface leads to a natural behaviour of the detail features. The correspondingreconstruction operator can be implemented efficiently by a hierarchical iterative relaxation scheme, providingclose to interactive response times for moderately complex models.Based on this representation we implement a multiresolution editing tool for irregular polygon meshes that allowsthe designer to freely edit the base surface of a multiresolution model without having to care about self-intersectionsin the respective detailed surface. We demonstrate the effectiveness and robustness of the reconstructionby several examples with real-world data.Item Adaptive Space Deformations Based on Rigid Cells(The Eurographics Association and Blackwell Publishing Ltd, 2007) Botsch, Mario; Pauly, Mark; Wicke, Martin; Gross, MarkusWe propose a new adaptive space deformation method for interactive shape modeling. A novel energy formulation based on elastically coupled volumetric cells yields intuitive detail preservation even under large deformations. By enforcing rigidity of the cells, we obtain an extremely robust numerical solver for the resulting nonlinear optimization problem. Scalability is achieved using an adaptive spatial discretization that is decoupled from the resolution of the embedded object. Our approach is versatile and easy to implement, supports thin-shell and solid deformations of 2D and 3D objects, and is applicable to arbitrary sample-based representations, such as meshes, triangle soups, or point clouds.Item A Finite Element Method on Convex Polyhedra(The Eurographics Association and Blackwell Publishing Ltd, 2007) Wicke, Martin; Botsch, Mario; Gross, MarkusWe present a method for animating deformable objects using a novel finite element discretization on convex polyhedra. Our finite element approach draws upon recently introduced 3D mean value coordinates to define smooth interpolants within the elements. The mathematical properties of our basis functions guarantee convergence. Our method is a natural extension to linear interpolants on tetrahedra: for tetrahedral elements, the methods are identical. For fast and robust computations, we use an elasticity model based on Cauchy strain and stiffness warping.This more flexible discretization is particularly useful for simulations that involve topological changes, such as cutting or fracture. Since splitting convex elements along a plane produces convex elements, remeshing or subdivision schemes used in simulations based on tetrahedra are not necessary, leading to less elements after such operations. We propose various operators for cutting the polyhedral discretization. Our method can handle arbitrary cut trajectories, and there is no limit on how often elements can be split.