One of the most useful features in Mudbox is how it handles layers. Each layer can be used to experiment or add variants to previously approved models. All images © Skymatter.

This past summer, the computer graphics industry continued the annual tradition of parading the latest and greatest software at SIGGRAPH. Absent from the proceedings was the then still embryonic, 3D brush-based, high resolution modeling app, Mudbox. Expectations were that Mudbox would be released in time for the show, but Skymatter, the software developer behind Mudbox, elected to continue to polish the feature set rather than release a piece of software they were not fully confident in. Fast forward to November, and Skymatter is ready to share their creation with the masses, almost. Rather than offer a wide release to any interested artist with cash in hand, Skymatter has instead chosen to offer a sort of pre-release to the folks who have been beta testing Mudbox over the past months. This is an interesting strategic move, as it gets the program out there and in use on real projects, while still allowing the development team to further refine features before a wide release opens the floodgates of feedback. Inevitably, this feedback will contain as much positive goodwill as it does bug fixing for the developers. Nevertheless, Skymatter hopes to offer the final release to the general public sometime this winter.

In simple terms, this release translates to digital sculptors as "freedom to choose." Up until now, these artists had to suffer through the minutiae of learning vertex and polygons-based modeling methods or learn an all-new modeling paradigm with ZBrush. Either option was capable of producing impressive results but usually meant late nights or extended schedules for the most detailed work. Mudbox changes all that with its brush-based, full 3D approach. In addition, the tool also makes smart use of layers, all while allowing artists to easily create effective normal and displacement maps.

When users first launch the Mudbox app, they find a clean, uncluttered UI layout. The app uses standard windows color schemes and drop down lists; certainly not a "back of the box" feature but a good sign that the developers are focusing their efforts on things of more importance at this early stage in the life of the software. Just below there are two tabs: one labeled "3D View" and the other "Image Browser." The 3D View tab is the main work window, where users sculpt and otherwise create. Directly below this 3D View window is the toolbar, which contains an array of brushes, as well as the three mainstay tools of any 3D app: translate, rotate and scale. On the right side of the screen the app displays three distinct areas, each with a variety of tabs. The first tab contains the Layers palette backed by the Object List tab. Below is the Properties tab, where users can change the properties of the currently selected tool. Finally, on the bottom right corner of the screen are the Falloff, Stamp and Stencil tabs, which will be more fully described later.

Character work is one obvious use for local subdivisions. By setting the face up to use many more subdivisions than the upper torso, an artist can create both the head and torso within a single model.

The design philosophy behind Mudbox seems to inform every decision the developers have made, sticking to a "keep it simple" approach wherever possible. This is readily apparent when new users launch the app for the first app with a goal in mind of producing something interesting with minimal effort. Once the app is up, a user can either create a basic mesh, from the handy "mesh" drop down list or they can import a variety of 3D file format flavors, including the universal .OBJ format, directly into Mudbox. Getting started with an app this powerful is unusual, to say the least.

Once the basic mesh is imported user can begin sculpting without any further preparation, although this is a great time to make that first iterative save. Users have the option, at anytime, to subdivide their mesh to allow for greater detail. Beginning with a default Mudbox Sphere users can use the brush-based tools to push and pull the geometry until it is in the rough form they desire. A quick subdivision at this point makes it so that the artist can put in the next level of shaping and begin to suggest features such as eyes and cheekbones. Continuing along, subdividing, followed by a detailing pass, is not only smart workflow but it also follows traditional sculpting methods of getting the overall form right first and then focusing on details. Within just a few minutes of sculpting in Mudbox, an artist can have a highly detailed mesh that would have taken hours to produce with other 3D tools.

In its assortment of brush-based sculpting tools, Mudbox contains several options to suit a wide variety of needs. The most useful tool in the app is likely the Soft brush. This brush can paint everything from detail to large-scale geometry shifts. Users have the option of manipulating both brush scale and strength with single "click and hold" hotkeys. This style of hotkey works especially well when using a graphics tablet, which should go without saying is a must for Mudbox. The other brush tools range from niche use, to tools such as "Pinch," which at first may not seem very useful but pays off when you need to accomplish something like a wrinkle in flesh. This tool allows artists to pull two sections of geometry together, creating a fold or wrinkle.