Sculpting and modeling in CGI have both been around for a while, but generally we see modeling more often than digital sculpting. Digital sculpting is also gaining in popularity these days. But which is better to use? Is there one that’s better to use? Does it depend? The argument is actually quite interesting.
There are many people out there who will swear by digital sculpting and generally use digital sculpting for most things. There’s also the opposite camp who believe in solely using modeling programs like Maya for everything. Then there’s the one’s in between who use both for different things. I started off my CGI work using a program called 3D Canvas and then moved on to Autodesk Maya. Most of what I’ve done has been primarily modeling work. I myself only recently started using ZBrush to dabble in digital sculpting. It was also the first time I had to use a tablet and pen for working with CGI. What I made with ZBrush was the following:
What I found really interesting about sculpting is how intuitive it is, especially with the pen and tablet set up. I have generally found modeling characters and organic things to be fairly difficult. As most will tell you, modeling living things in something like Maya is fairly demanding. It’s certainly not impossible, but it does push the skill level with Maya. I’ve had to model a character in Maya as well. Here’s what he looked like:
Try not to look too closely to the texturing. Instead, look at the geometry of the characters (which admittedly is tough, since much of Raktabija is covered in armor and the shot is in a dark background). What’s interesting to note is that Raktabija is the first time I modeled a character ever (and consequently the first time I modeled a character in Maya), while the Naga is the first time I ever did digital sculpting. You’ll immediately notice that the Naga has far more geometric details than Raktabija. Now to be fair, I did have a much better idea of form when I did my ZBrush sculpt than when I did the Maya character model, but even then, notice that the Naga is a more complicated form than Raktabija. Raktabija is basically just a human character. The Naga is a 4 armed, fanged, half man, half snake creature.
Where am I trying to go with this? The point is that ZBrush was by far easier for me to use to create the character/creature than Maya was. ZBrush is an excellent program, developed by Pixologic, that allows for very easy sculpting. Sculpting in general lends itself very much to creating creatures and organic forms. It’s very easy to cheat out a shape out of a sphere, or a cube in digital sculpture, and very easy to make it inherently look organic. The reason for this is also what will lead me to the downsides of digital sculpting. Digital sculpting focuses on allowing the user to sculpt, as if he/she were using clay. In order to achieve this, the subdivisions of the geometry tend to exponentially increase as more detail is added. The result is that the final topology, or the way the polygons are laid out on the mesh, is not under your control as much. The thing is that most organic forms, like humans, creatures, etc., are also very complicated, meaning that to represent them in detail in 3d space usually means using a ton of polygons. The downside of a ton of polygons is obvious: computational time for rendering will shoot up. This especially matters for game engines, which don’t tolerate high poly count models. Modeling, while much tougher to do since it’s not nearly as intuitive, does afford much greater control over things like topology, edge flow, and where the subdivisions are. So while it can take much more time to create the organic form, it’s also going to be an inherently lower poly-count than a digital sculpture will. It is also entirely possible to create a high detail organic model in programs like Maya, but again, it’s not as straightforward as it would be in programs like ZBrush. Then there’s also considering exporting your model to other programs for things like texturing, rigging, and animation. Again, most programs have a really tough time dealing with the gigantic poly counts that digital sculpting generates. So it’s another potential downside.
Now to be fair, programs like ZBrush have an excellent set of retopologizing tools that will reduce poly count and also redistribute polygons more evenly over the mesh. It is entirely possible also to create a texture map for the details on a low poly version of the sculpt and export that to other programs like Maya for a render. Blizzard uses this pipeline for many of its game projects. And with increasing computational power, it’s becoming easier to do and deal with as well. For projects like CG movies or single images, the poly count isn’t as important, since the final image is what really matters, not the render time. And for these reasons, digital sculpting, in my opinion, has a very bright future ahead, even in the game industry.
But is digital sculpting great for everything? In my experience, no. Digital sculpting is great for building the organic forms, but if you’re doing hard surface modeling, you’d be far better off using something like Maya. I sculpted the belt for the Naga in ZBrush and my experience from that is that while you can certainly sculpt hard surfaces in ZBrush, it’s a lot harder since sculpting inherently lends itself more to organic forms. It’s much easier to make some organic looking with something like clay than to make it look like a hard surface. Again, there are many people who do everything in ZBrush, but the hard surfaces do take more time than in something like Maya. If you want to, sure, you could certainly display your skill by sculpting everything, and my hats off to you for doing it, but I prefer using tools to ease my work, so generally I stick with hard surface modeling in Maya rather than ZBrush.