Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Better Shadows With New Algorithm

15.12.2003


Shadows are extremely important in making the graphics in 3D games and Virtual Reality applications seem natural. Soft shadows in real-time applications has largely been an unsolved problem, but now an algorithm is being introduced that will solve the problem and open many possibilities.



In his doctoral dissertation, Ulf Assarsson at the Department of Computer Engineering, Chalmers University of Technology in Göteborg, Sweden, presents a newly developed algorithm that can create shadows of a much higher quality than ever before for applications with limited calculation time.

What is this good for?


”Apart from the obvious fact that it enhances the feeling of presence in all sorts of games, the technique can be of great interest in other fields that apply Virtual Reality, such as the auto industry, architecture, and various Internet applications,” he says.

Here’s how it works

Sources of light that have some kind of area or volume, that is, all real sources of light, create gradual transitions on shadow edges from no shadow to full shadow. Graphics usually produce shadows with knife-sharp transitions from no-shadow to shadow - so-called “hard shadows” - since they don’t require as much time to calculate.

The larger the light source is, the more diffuse the transition becomes, and it is therefore highly desirable to be able to simulate these “soft shadows” even for real-time applications that only allow some 20 milliseconds to calculate a whole image, if the goal is to produce 50 images per second.

The algorithm solves the problem by utilizing the new programming capacity offered by the latest graphics cards, which are now available even in cheap game cards.

Research on soft shadows started in the 1970s. It has come to the fore again in the last two years.

What’s so special about your algorithm?

“What’s unique is that it can efficiently make use of the new possibility of programming graphics cards, which are now being included in cheap game cards. This makes it extremely fast. There are a few other new algorithms, but they are either way too slow or produce low quality shadows. We are also aware of a number of up and coming inventions that will strengthen our algorithm, so we believe in its potential,” says Ulf Assarsson.

The technology can also handle shadows from more advanced light sources, like the flames of a fire. The algorithm has thus far attracted the attention of players not only in the game industry like Microsoft XBox but also the film industry, where it can be used in programs for computer-generated special effects.

First in Sweden

The algorithm was introduced last summer at SIGGRAPH - the world’s largest and most important computer graphics conference - and constituted one of the first two wholly full-length articles from Sweden ever chosen for the conference.

Ulf Assarsson’s dissertation was directed by Associate Professor Tomas Akenine-Möller, who played a major role in the work.

Jorun Fahle | alfa
Further information:
http://www.chalmers.se

More articles from Information Technology:

nachricht Drones that drive
27.06.2017 | Massachusetts Institute of Technology, CSAIL

nachricht Ahead of the Curve
27.06.2017 | Institute of Science and Technology Austria

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>