Contents

• News
• Introduction
• Papers
• Requirements
• License
• Download
• Installation
• Documentation
• Links

News

• May 18, 2002. SOLID version 2.1.0 is available for download.
• October 18, 2000. SOLID version 2.0.2 is available for download.
• October 16, 2000. SOLID is now hosted at sourceforge.
• March 25, 2000. A GLUT version of the GJK demo is now avalable in the GJK-engine. Thanks Christophe Barbé for the GLUTification.
• May 22, 1999. A fast and robust implementation of the Gilbert-Johnson-Keerthi algorithm, which is the 'heart' of SOLID, is released as a separate library, called GJK-engine. SOLID uses the GJK algorithm for testing intersections, determining common points, and computing pairs of closest points of convex objects. An archive file containing the sources for building the library and an OpenGL demo application can be downloaded here. See the papers section for an explanation of this implementation.

 

Introduction

• Object shapes are represented by primitive shapes (box, cone, cylinder, sphere), and complexes of polytopes (line segments, convex polygons, convex polyhedra). A single shape can be used to instantiate multiple objects.

 
• Motion is specified by translations, rotations, and nonuniform scalings of the local  coordinate system of each moving object. These changes can be given absolute or relative to the previous frame. The local coordinate system can also be set according to an array of sixteen floats or doubles representing a 4x4 column-major matrix of an affine transformation, as used in OpenGL.

 
• Deformations of complex shapes can be specified using client-defined vertex arrays.

 
• Collision response is defined by the client by means of call-back functions. Response may be defined per object pair, for all pairs containing a specific object, and as default for all pairs of objects.

 
• Response call-backs can use collision data describing the configuration of a pair of colliding objects. As collision data can be used a point common to both objects, and the closest point pair of the objects from the previous frame. The latter response type can be used for approximating the collision plane in physics-based simulations.

 
• Frame coherence is exploited by maintaining a set of pairs of proximate objects (incremental sweep and prune of axis-aligned bounding boxes), and caching separating axes for these pairs.  This feature is optional and may be turned on/off at any time during a simulation.

Papers

G. van den Bergen. "Efficient Collision Detection of Complex Deformable Models using AABB Trees." Journal of Graphics Tools, 2(4):1-13 (1997), PDF (164Kb).

G. van den Bergen. "A Fast and Robust GJK Implementation for Collision Detection of Convex Objects." Journal of Graphics Tools, 4(2):7-25 (1999), PDF (79Kb).

Requirements

For fast intersection tests and distance computations between convex polyhedra, SOLID relies on the Qhull library for convex hull computations.  Qhull is a free software library and is available for most platforms. Note that a properly operating SOLID library  can be compiled without using Qhull. However, it is recommended to incorporate Qhull for a better performance when polyhedra are used.

License

Download