194 citations · 543 across the 38 of their papers we have counts for
21 papers · 1 filter
Line-Torus Intersection for Ray Tracing: Alternative Formulations
Vaclav Skala
Intersection algorithms are very important in computation of geometrical problems. Algorithms for a line intersection with linear or quadratic surfaces are quite efficient. However…
A Comparison of Fundamental Methods for Iso-surface Extraction
Jan Patera, Vaclav Skala
In this paper four fundamental methods for an iso-surface extraction are compared, based on cell decomposition to tetrahedra. The methods are compared both on mathematically genera…
Robust Surface Reconstruction from Orthogonal Slices
Radek Svitak, Vaclav Skala
The surface reconstruction problem from sets of planar parallel slices representing cross sections through 3D objects is presented. The final result of surface reconstruction is al…
HS-Patch: A New Hermite Smart Bicubic Patch Modification
Vaclav Skala, Michal Smolik, Lukas Karlicek
Bicubic four-sided patches are widely used in computer graphics, CAD/CAM systems etc. Their flexibility is high and enables to compress a surface description before final rendering…
BS-Patch: Constrained Bezier Parametric Patch
Vaclav Skala, Vit Ondracka
Bezier parametric patches are used in engineering practice quite often, especially in CAD/CAM systems oriented to mechanical design. In many cases quadrilateral meshes are used for…
S-patch: Modification of the Hermite parametric patch
Vaclav Skala, Vit Ondracka
A new modification of the Hermite cubic rectangular patch is proposed: the S-Patch, which is based on the requirement that diagonal curves must be of degree 3 instead of degree 6 a…
New Geometric Continuity Solution of Parametric Surfaces
Vaclav Skala
This paper presents a new approach to computation of geometric continuity for parametric bi-cubic patches, based on a simple mathematical reformulation which leads to simple additi…
A New Approach to Line-Sphere and Line-Quadrics Intersection Detection and Computation
Vaclav Skala
Line intersection with convex and un-convex polygons or polyhedron algorithms are well known as line clipping algorithms and very often used in computer graphics. Rendering of geom…
Point-in-Convex Polygon and Point-in-Convex Polyhedron Algorithms with O(1) Complexity using Space Subdivision
Vaclav Skala
There are many space subdivision and space partitioning techniques used in many algorithms to speed up computations. They mostly rely on orthogonal space subdivision, resp. using h…
A New Robust Algorithm for Computation of a Triangle Circumscribed Sphere in E3 and a Hypersphere Simplex
Vaclav Skala
There are many applications in which a bounding sphere containing the given triangle E3 is needed, e.g. fast collision detection, ray-triangle intersecting in raytracing etc. This…
Projective Geometry, Duality and Plucker Coordinates for Geometric Computations with Determinants on GPUs
Vaclav Skala
Many algorithms used are based on geometrical computation. There are several criteria in selecting appropriate algorithm from already known. Recently, the fastest algorithms have b…
Clipping and Intersection Algorithms: Short Survey and References
Vaclav Skala
This contribution presents a brief survey of clipping and intersection algorithms in E2 and E3 with a nearly complete list of relevant references. Some algorithms use the projectiv…
Two Methods for Iso-Surface Extraction from Volumetric Data and Their Comparison
Vaclav Skala, Alex Brusi
There are various methods for extracting iso-surfaces from volumetric data. Marching cubes or tetrahedra or raytracing methods are mostly used. There are many specific techniques t…
A New Radial Basis Function Approximation with Reproduction
Zuzana Majdisova, Vaclav Skala
Approximation of scattered geometric data is often a task in many engineering problems. The Radial Basis Function (RBF) approximation is appropriate for large scattered (unordered)…
Least Square Error Method Robustness of Computation: What is not usually considered and taught
Vaclav Skala
There are many practical applications based on the Least Square Error (LSE) approximation. It is based on a square error minimization 'on a vertical' axis. The LSE method is simple…
O(lgN) Line Clipping Algorithm in E2
Vaclav Skala
A new O(lg N) line clipping algorithm in E2 against a convex window is presented. The main advantage of the presented algorithm is the principal acceleration of the line clipping p…
A Fast Algorithm for Line Clipping by Convex Polyhedron in E3
Vaclav Skala
A new algorithm for line clipping against convex polyhedron is given. The suggested algorithm is faster for higher number of facets of the given polyhedron than the traditional Cyr…
A Comparative Study of LOWESS and RBF Approximations for Visualization
Michal Smolik, Vaclav Skala, Ondrej Nedved
Approximation methods are widely used in many fields and many techniques have been published already. This comparative study presents a comparison of LOWESS (Locally weighted scatt…
A two-level approach to implicit surface modeling with compactly supported radial basis functions
Rongjiang Pan, Vaclav Skala
We describe a two-level method for computing a function whose zero-level set is the surface reconstructed from given points scattered over the surface and associated with surface n…
Fractions, Projective Representation, Duality, Linear Algebra and Geometry
Vaclav Skala
This contribution describes relationship between fractions, projective representation, duality, linear algebra and geometry. Many problems lead to a system of linear equations. Thi…
Continuous Global Optimization in Surface Reconstruction from an Oriented Point Cloud
Rongjiang Pan, Vaclav Skala
We introduce a continuous global optimization method to the field of surface reconstruction from discrete noisy cloud of points with weak information on orientation. The proposed m…