Combustion.(Discreet's desktop compositor)(Software Review)(Evaluation)

High-end desktop compositing from Discreet

Discreet's Combustion is a robust 3D compositing package for Windows NT and the Macintosh that supports compositing, painting, motion tracking, and keying, all in one package. It's like a little sibling to Discreet's popular Flame, Flint, and Inferno SGI-based digital-effects toolsets that brings true high-end compositing to the desktop.

Combustion supports Adobe Premiere and After Effects plug-ins, which you can copy to Combustion's plug-in directory after you install the program. Navigating the software's interface is fairly straightforward, with ports for viewing footage at the top of the screen, playback controls in the middle, and user controls toward the bottom.

Bringing footage into the package is easy. Combustion supports about 20 standard image file formats, including TIF, Targa, QuickTime, AVI, and Cineon (for film work). The two most interesting formats are RLA and RPF, both of which can encode 3D data in an image file. This allows Combustion to extract such data as the Z depth of each pixel, as well as geometry, motion, and camera data, thereby simplifying the compositing process and making your results more accurate.

When loaded, images are stored in the program's Workspace, which can contain one or more composites that can be layered together to create more complex scenes. Interaction is fast. Discreet has included a RAM player for faster previews, as well as a draft mode that degrades the quality of the image so that effects render quickly, enabling you to work faster.

Most compositing packages work in 2D space, whereby each element is simply layered on top of the next. Combustion can work well in this way, but its real strength is that it's a true 3D compositor. You can position each element along not only the X and Y axes, but also the Z axis to provide true depth. This is a much more flexible way of working because it enables you to easily animate elements from front to back in an image. Because each element has depth, it is easy in Combustion to simulate real-world effects such as perspective, as well as perform any number of cool 3D tricks, such as spinning elements in space. Combustion also includes lights and cameras. The cameras provide a way to view your work from different angles, and you can use them to simulate real-world camera effects such as rack focus. The lights work much as they do in 3D packages, and they can be used to cast shadows through one bitmap onto ...