The official home page for
BART: A Benchmark for Animated Ray Tracing
by Jonas Lext, Ulf Assarsson, and Tomas Möller
Department of Computer Engineering, Chalmers University of Technology, Sweden.


Contents:
Description of BART
Download BART
Projects that used BART

Test scene: Kitchen
Test scene: Robots
Test scene: Museum



Description of BART

Abstract: Due to the advent of ray tracing at interactive speeds and because there is an absence of a way to measure and compare performance and quality of ray traced scenes that are animated, we present an organized way to do this fairly and accurately in this proposal for BART: A Benchmark for Animated Ray Tracing. This is a suite of test scenes, placed in the public domain, designed to stress ray tracing algorithms, where both the camera and objects are animated parametrically. Equally important, BART is also a set of rules on how to measure performance of the rendering. We also propose how to measure and compare the error in the rendered images when some kind of approximation algorithm has been used.

Informal description: We were and still are interested in efficient algorithms for computer graphics. In this case we focused on ray tracing algorithms for animated scenes. The main reason for this is that real-time or interactive ray tracing is quite possible to do on multiprocessor computers. So, to be able to compare different acceleration schemes, we set out to compile a suite of test scenes for this. We currently have three scenes described below that we have put into the public domain. Each scene was designed to stress ray tracing algorithms in general. In order for the user of BART to make a fast implementation, we provide a simple C-parser for the file format (it takes about half a day to implement), and some animation code. The benchmark may also be used to: 1) compare algorithms using polygon rendering hardware (e.g., OpenGL), 2) compare global illumination and radiosity algorithms, 3) compare motion blur algorithms, but was not designed specifically for these areas of interest.



Test scene: Kitchen

Short description:
The Kitchen scene was designed to stress: 1) the teapot in the stadium problem (which is done by having a small car driving around in room; there are also very small, detailed objects such as door knobs, 2) cache performance (this is done by having a scene which is on the order of a magnitude larger than current L2 caches), 3) different hierarchies (this is implemented by having and hierarchically animated (using translations, rotations, and scalings) car in the scene), and 4) approximation algorithms (this is implemented by having a sequence with high frame-to-frame coherency followed by very little frame-to-frame coherency). Depending on the acceleration data structure used and how these are applied to the objects in the scene, there is also the possibility of bounding volume overlap, when the car moves under the table and around the chairs. The scene contains more than 110,000 polygons and more than 7 MB of textures.

Screenshots:


MPEGs:
400x300, 800 frames, 16 MB
800x600, 800 frames, 69 MB



Test scene: Robots

Short description:
The Robot scene was designed to include the following stresses: 1) hierarchical animation, by the 18 moving parts of each warrior robot and the corresponding hierarchical keyframe animated transforms, 2) change of distribution; the distribution of objects goes from fairly balanced at start to highly unbalanced in the end of the animation, where all robots are clustered at the center of the scene, and 3) data structure overlap; bounding volumes for parts in the arms and legs will overlap at the joints. The scene also contains the the teapot in the stadium-problem since the 10 robots each contain a lot of small details and are surrounded by large low-detailed skyscrapes.

Screenshots:


MPEGs:
400x300, 800 frames, 15 MB
800x600, 800 frames, 90 MB



Test scene: Museum

Short description:
The Museum scene was designed to stress the building of the efficiency data structures for ray tracing. The scene is a simple room in a museum with an animated abstract piece of art in the middle of the room. This object consists of a number (from 64 to 65,536 depending on the complexity level) of triangle patches (triangles with normals at each vertex). Each triangle patch has description of its vertices and normals at five different times. For a certain time t, the two triangle patches closest to t are used to create a new triangle patch by interpolation. Since each triangle patch is moving independently of each other, this forces every known (to us) acceleration scheme to rebuild its data structure for that object every frame.

Screenshots:


MPEGs:
400x300, 300 frames, 3 MB
800x600, 300 frames, 11 MB



Download BART



Acknowledgements:

Thanks to Joachim Helenklaken for modeling the kitchen scene (except the glass dragon which was modeled by Takeo Igarashi, and the animations which was done by Jonas Lext), and to Jens Larsson for modeling the robots scene (animation done by Ulf Assarsson).



Projects that have used BART:



Last update by Tomas Akenine-Möller on June 2, 2003