ZBrush 2 review

Forget everything you know.

Everything you know about 3D modelling and 2D painting, that is. Because if you approach Pixologic's incredible ZBrush 2 painting and modelling software with any preconceptions, you're in for a tough time. We know. We did, and we were.

So what is ZBrush exactly - a paint program? A 3D modeller? Well it's both. And neither. At the heart of ZBrush lies the idea of the 'Pixol' or '2.5D paint'. Normal pixels contain information about colour and position, and maybe even alpha information. Pixols also contain information about scene depth, rotation and material properties, and can pick up information about lighting and shade. There's actually a real-time 3D rendering engine responsible for the display of the Pixol paint.

ZBrush's interface contains a small canvas (640 x 480 by default) surrounded by a lot of interface. ZBrush eschews menus in favour of palettes: these are drop-down dialog boxes accessed from ZBrush's menu bar (the Mac menu bar is just used to load interfaces and Zscripts). These palettes can be docked to either side of the canvas and you can create custom floating palettes. Customisable interfaces are de rigeur at the moment (no bad thing) and ZBrush's is one of the most malleable out there. However, it can be pretty bewildering to new users, as it takes a while to work out where everything is. There's a reduced Starter interface if you just can't cope, though.

The basic 'atom' of ZBrush is the tool. These can be brushes (Standard, Paint Roller, Fibre, Hook and 3D elements) and primitives such as planes, spheres, cubes, spirals and so on. You can paint these onto the canvas, apply materials to them, and move, scale and rotate them. Unlike standard 3D programs, you can only apply the Transform modes to a tool before the next tool is selected: after that, they're dropped onto the canvas and become uneditable, although you can still paint 'depth' onto them. This takes some getting used to, but is really no different to standard 2D paint behaviour. You can paint complex materials onto elements using effects brushes (such as the Fibre brush to simulate vegetation) and you have great control over the materials interface, which enables you to paint fully rendered materials directly onto the canvas in real time.

This was where it ended in version 1, but this new version boasts some pretty amazing 3D capabilities. The ZSphere tool enables you to block out a 3D form by using ZSpheres' live metaball-like capabilities. Once you achieve a proxy form, you can 'skin' the ZSpheres into a rough mesh. This is where things get really interesting. Meshes in ZBrush can be increased or decreased interactively in resolution through eight levels of subdivision. Normal 3D modelling workflow has you working at ever-increasing and ever-smaller levels of detail. ZBrush enables you to work at the highest resolution available and then drop back to a rough cage to make changes in bulk form - even back to the ZSpheres themselves. The freedom this gives to modelling is quite outstanding. Our only reservation is that sometimes we got the spinning beachball for around 10 seconds when changing resolutions.

The other breathtaking feature of ZBrush is the way you apply its painting tools to 3D modelling. In other programs, you add surface detail by moving vertices around, but ZBrush lets you paint surface detail, from muscle definition, down to spots, scales and scratches. Most of these effects can be applied using just the Move and Draw tools. The Move tool shifts vertices around, but the Draw tool adds (or subtracts) mass to the model, offering some amazing sculpting possibilities. To produce realistic results, you need to have a good feeling for what the brush parameters do. Those in ZBrush are Draw Size, Z Intensity and Focal Shift, but the rest of the world knows them better as Radius, Flow and Edge Softness. After a bit of practice, it's possible to produce some quite amazing organic forms just with a pen and graphics tablet.