Consumer, Home and Recreat~on Terrain Simulation

elow is a view of Planet Earth from on the delicate balance among those forces. orbit. It is a frame from the 42-minute A highlight of the film is a 100- Imax film Blue Planet, which has been second computer-generated animation of Bseen by more than eight million pee a flight and earthquake simulation along ple at giant screen Imax theatres. Produced California's San Andreas Fault. This by Imax Space Technology, Inc., a subsidiary sequence, created by the Visualization and of Trax Corporation, Toronto, Ontario, Blue Earth Sciences Application (VESA) Group of Planet is presented by the Smithsonian Jet Propulsion Laboratory (JPL),employed Institution's National Air and Space Museum new three-dimensional perspective render- and Lockheed Corporation in cooperation ing (3DPR) techniques, a technology in with NASA. development at JPL since 1985. The Bhe Much of Blue Planet features breath- Planet sequence marked a milestone in taking views of Earth filmed in orbit on five transferring 3DPR technology to the private Space Shuttle flights by astronauts trained to sector; it had been employed in earlier films, operate the IMAX@cameras, which produce but never on the scale demanded by the an image three times larger than standard San Andreas simulation. 70-millimeter motion picture film. The film, The accompanying images are sam- says Imax, "gives audiences worldwide a view ple frames from the computer-animated of their global home that is as close to being sequence, developed from data sent from in orbit as one can possibly get." orbit by the Landsat Earth resources moni- Blue Planet, however, is more than an toring satellites. At top right is a view of orbital travelogue; it is a film with a message, California looking northwest over the Salton a depiction of the powerful forces that affect Sea with San Diego at far left and a portion Earth from within and without, and the of the Colorado River at far right. The effects of natural and man-made influences lower right photo is centered on San Francisco with Mt. Shasta on the horizon at left photo and the Sierra Nevada Range at center and right. The 3DPR work at JPL is part of a broader program of scientific visualization, a field devoted to exploring new ways of pre- senting voluminous data to scientists, allow- ing experts in various fields to understand large volumes of data quickly and easily. One such technique is terrain rendering, a type of scientific visualization employed by scientists as an effective means of recognizing patterns in remotely sensed data. Terrain rendering involves superim- posing image data on digital elevation maps to produce a three-dimensional simulation of the actual terrain. When image and eleva- create 2,160 frames, which were sent on tapes to Imax and there transferred to film. Development and use of an tion data are thus combined, the topography advanced pyramidal terrain rendering tech- and imagery become much dearer and may nique reduced what would have taken close suggest further information, for example, to a year of computer time by earlier meth- what is beneath the surface. ods to about 50 days. The Blue Planet task required devel- In addition to the commercial spin- opment of new technology to make possible off, the new techniques have provided NASA terrain rendering of very large digital images an important payback. Large mosaics of within the short period allowed by the film Venus were assembled from the data sup company's schedule. The data that made plied by the Magellan spacecraft. The the animation possible was an image mosaic visualization group at JPL and the Magellan of California constructed from Landsat science team were able to produce high- Multispectral Scanner scenes, combined resolution terrain animations of Venus from with more detailed Landsat Thematic these mosaics. JPL continues to develop Mapper data for the San Francisco area. new perspective rendering technologies as a Elevation data for terrain mapping was means of coping with the vastly increased obtained from the U.S. Geological Survey. volume of remote sensor data expected in To create the San Andreas fight the coming decade. simulation, the VESA Group used 727 @IMAXis a registered wademark of Imax Corporation, megabytes of image and elevation data to Toronto, Ontario.