Escape from flatland

THE third dimension is everywhere these days. Powerful computer programs allow designers to work in 3D; virtual-reality goggles immerse users in an ultra-realistic illusion in which they can walk around and pick up objects; and 3D printers are being used to make an increasing variety of things, including buildings (see page 13). But manipulating and shaping objects in 3D in a computer can be tricky, typically requiring a piece of dedicated hardware used as a pointing device, such as a mouse, stylus pad or a specialist controller operated with joysticks.