Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer Science Fog Machine Improves Computer Graphics

18.04.2008
UC San Diego computer scientists have created a fog and smoke machine for computer graphics that cuts the computational cost of making realistic smoky and foggy 3-D images, such as beams of light from a lighthouse piercing thick fog.

By cutting the computing cost for creating highly realistic imagery from scratch, the UCSD computer scientists are helping to pull cutting edge graphics techniques out of research labs and into movies and eventually video games and beyond. The findings are being presented this week at Europe’s premier computer graphics conference, Eurographics 2008 in Crete, Greece on April 17.

This new work is part of a shift in the computer graphics, film, animation and video game industries toward greater realism through the use of “ray tracing algorithms.” Much of the realism in ray tracing technologies comes from calculating how the light in computer generated images would behave if it were set loose in the real world and followed the laws of nature.

At the heart of the new UCSD advance are computationally slimmed “photon mapping” algorithms, which are a subset of the ray tracing algorithms. The computer scientists found a way to collect all of the pertinent lighting information in computer generated scenes at once, which made the new photon mapping approach more lightweight than conventional photon mapping. This technique is especially good for creating smoky, foggy or cloudy scenes and producing images that do not have much unwanted visual noise.

“We took an algorithm that is already great and made it more efficient,” said Wojciech Jarosz, the first author on the new Eurographics paper and a Ph.D. candidate from the Department of Computer Science and Engineering at UCSD’s Jacobs School of Engineering.

This approach is an improvement upon the Academy Award winning photon mapping technique first developed by UCSD computer science professor Henrik Wann Jensen during his doctoral studies. Jensen is a co-author on this new Eurographics paper, along with UCSD computer science professor Matthias Zwicker.

To date, ray tracing algorithms are primarily used in settings where ultimate realism is required and where heavy computation can be tolerated – such as offline environments that do not require real-time image rendering. An ice-cube-filled drink in the animated movie Final Fantasy is one example of photon mapping in the movies.

Computational constraints, however, have limited the use of photon mapping and other ray tracing approaches in places where speed and lightweight computation are crucial – such as video games. These domains have embraced an approach called rasterization, which is faster, but unable to easily simulate advanced lighting effects.

The new photon mapping approach from UCSD, and related advances, are poised to increase the reach of ray tracing algorithms – perhaps even into the domain of 3-D animation software for the general public and video games. The Larrabee chip that Intel is working on is just one indication that ray tracing technologies may play an increasing important role in consumer oriented graphics of the future.

Computerized Fog Costs

Much of the richness in images created with photon mapping algorithms comes from precise accounting for the amount of light is in a scene and where that light is. Photon mapping algorithms provide a way to follow the light around the scene, as it bounces off various objects and lands on other objects. Photon mapping can also determine how light will interact with fog, smoke or other “participating media” that absorb, reflect and scatter some portion of the light – a task that has been traditionally quite computationally costly to perform because it requires sampling the light at many locations in order to make sure that nearly all the light is accounted for.

“Instead of computing the light at thousands of discrete points along the ray between the camera and the object, which is the conventional approach, we compute the lighting along the whole length of the ray all at once,” said Jarosz.

To Movies, Then Milk

This more efficient approach to photon mapping could be extended well beyond foggy and smoky scenes, because many materials, including skin, milk and plants, behave like fog or smoke, but on a more limited basis.

“Most natural materials behave like really dense fog because light penetrates them to a limited extent, so this work has a lot of potential future applications,” said Jensen, who published work in 2007 at SIGGRAPH on a graphics model capable of generating realistic milk images based on the fat and protein content. This research is pushing the field of computer graphics into the realms of diagnostic medicine, food safety and atmospheric science.

While photon mapping and other ray tracing algorithms that more closely mimic the natural world are making their way into movie special effects and animated films, Jarosz does not expect movies and video games to strictly follow the laws of nature.

“In live action movies, the lighting is incredibly controlled. If a character walks into a shadow, they will add light to the face even if you would never get that kind of light in a real shadow. The composition on the screen must tell the story and not distract the viewer. Realism doesn’t always matter. It’s the movies.”

Eurographics 2008 Paper: “The Beam Radiance Estimate for Volumetric Photon Mapping,” by Wojciech Jarosz, Matthias Zwicker and Henrik Wann Jensen at the Computer Science and Engineering Department, University of California, San Diego’s Jacobs School of Engineering.

Daniel Kane | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Information Technology:

nachricht Researchers achieve HD video streaming at 10,000 times lower power
20.04.2018 | University of Washington

nachricht An AI that makes road maps from aerial images
18.04.2018 | Massachusetts Institute of Technology, CSAIL

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>