Issue: Volume: 22 Issue: 11 (November1999)

Spotlight: Polygons-to-NURBS Products Proliferate

A new family of computer graphics products has emerged this year--software programs that create NURBS models from polygonal versions. Scanning is the most obvious application for this technology. Physical objects, including human beings, can be digitized and the resulting images converted to high-density NURBS models for use in manufacturing or animation. But other possibilities include the conversion of pre-existing polygonal files. Game developers, for example, maintain libraries of polygonal game characters, says Peter Ryce, director of product management, entertainment applications, for the software company Paraform. When these characters are needed to grace the covers of boxes, magazines, or marketing materials, Paraform can be used to create print-quality NURBS models. In the past, says Ryce, "These companies had to farm out the NURBS work to third parties, who might not even represent the characters correctly."
Image courtesy of Paraform

Paraform is just one of the new breed of polygons-to-NURBS programs. Others include geomagic Studio from Raindrop Geomagic, CySlice 2.0 from the Australian company headus, and EM 3.0 from InSpeck, a maker of optical digitizers. Each of these products has an emphasis and capabilities slightly different from the other--Studio`s main area is CAD, while Paraform, CySlice, and EM target the entertainment industries. But the goal of each program is the same: to make NURBS models quicker and easier to produce.

Geomagic Studio is a $19,995 program suite (consisting of the company`s Wrap and Shape applications) that stands out for its speedy and automatic NURBS model creation. Users do not have to create cross-sections or patches, because Shape does it for them. In addition, the Wrap program automatically converts point-cloud data from scans to polygonal models. In a non-scanning application, Raindrop Geomagic recently teamed with Sensable Technologies (Cambridge, MA) to create a NURBS model of an alien`s head (above) that was sculpted on-screen in Sensable`s Freeform modeling system, then converted to NURBS using Shape.

A recent addition to the entertainment arena is the $15,000 Paraform program, which debuted at Siggraph this year, though it underwent extensive field tests beforehand. (Paraform was used, for example, to create the giant crocodile in the movie Lake Placid.) Though not automatic like geomagic Studio, Paraform`s manually defined path layout and parametrization control offer users a high level of choice--a plus for experienced NURBS modelers who may wish to assign different levels of detail to their models.

In comparing the two programs, California-based industry analyst Wanda Meloni says, "Paraform`s manual process allows users a great deal of flexibility. Raindrop Geomagic`s Shape is quick and easy to use because it`s automatic. It`s a real time-saver."

At $4000, CySlice 2.0 is a cost-effective polygons-to-NURBS solution from headus, a software developer and service bureau for Cyberware (Monterey, CA) scanners. Six years ago, headus began to develop programs to edit and produce NURBS models from Cyberware scans. Today, CySlice is a stand-alone product that can be used with any polygonal data, whether from scans or libraries. According to headus principal Jill Smith, CySlice`s surfacing tools have been designed for animators. That said, "We also have many customers who use the tools in CySlice to help them build surfaces in CAD packages."

Polygons-to-NURBS products can also be found as editing tools sold with high-end digitizers, similar to the way CySlice began. One example is EM 3.0 from InSpeck. This 3D package allows users to create models by merging the different views captured by the company`s digitizers. A recent addition to the product is the ability to generate a single-patch or multi-patch textured NURBS surface.

EM is sold bundled with InSpeck`s optical digitizers or as a $6000 stand-alone. It requires Windows 95/98/NT and 64mb of RAM. geomagic Studio requires Windows/95/98/NT and 128mb of RAM. An SGI IRIX version is also available. Paraform runs under Windows NT and requires 256mb of RAM; an SGI IRIX version is under development. CySlice runs under NT or SGI IRIX and requires 128mb of RAM.

Santa Clara, CA

Research Triangle Park, NC

Perth, Australia

Quebec City, Canada