We present efficient and accurate algorithms for interference detection among objects undergoing polynomial deformation. The scope of our algorithms include physically-based models undergoing dynamic simulation subject to non-penetration constraints, variational models, deformable models used in soft object animation, geometric models including polygonal meshes, parametric surfaces such as Bezier patches and B-splines, and solid models defined by such surfaces. Our algorithms use axis aligned bounding boxes and convex hulls of the objects to identify the object pairs in close vicinity. They use subdivision, convex hull properties and linear programming to perform surface intersection tests and loop intersection tests. Frame-to-frame coherence is utilized to achieve incremental computations. The resulting algorithms have been implemented and work well in practice. In particular we are able to compute all contacts accurately and at interactive speeds for flexible bodies undergoing second-order polynomial deformations.

Daistish is a tool that performs systematic algebraic testing similar to Gannon's DAISTS tool [2]. However, Daistish creates effective test drivers for programs in languages that use side effects to implement ADTs; this includes C++ and most other object-oriented languages. The functional approach of DAISTS does not apply directly in these cases. The approach in our work is most similar to the ASTOOT system of Doong and Frankl [1]; Daistish differs from ASTOOT by using Guttag-style algebraic specs (functional notation), by allowing aliasing of type names to tailor the application of parameters in test cases, and by retaining the abilities of DAISTS to compose new test points from existing ones. Daistish is a Perl script, and is compact and practical to apply. We describe the implementation and our experiments in both Eiffel and C++. Our work has concentrated on solving the semantics-specific issues of correctly duplicating objects for comparison; we have not worked on methods for selecting specific test cases.Daistish consists of a perl script and supporting documentation. The current distribution can be obtained via WWW at URLhttp://www.cs.unc.edu/~stotts/Daistish/

Abstract We present a methodfor simplifying the meshes produced as solutions to global illumination problems, reducing geometric complexity while retaining the perceived imagefidelity. The method has been applied to produce meshes of linearly, quadratically and cubically colour‐interpolated triangles. The goal of our work is to permit interactive rendering of more complex global illumination solutions through the application of simplification algorithms as well as the use of more powerful rendering primitives.