by Vanessa Trepanier
There are a few ways to make normal maps: Maya, zBrush, and programs like Crazy Bump for instance. While you can always let these programs do their stuff, adjusting a few settings here and there, you can always paint your very own normal maps from scratch with Photoshop and the nDo plug-in.
The nDo plug-in (which can be found here: http://cgted.com/) is an Action in Photoshop that can convert your texture map into a normal map, using the information you’ve painted in to create bumps, scratches, and hard surfaces. If you have a layer that’s full of a rocky texture for example, nDo will quickly turn that into a bumpy surface for your model at the click of a button. It also allows you to adjust a number of settings, from the depth of the cracks in the rock, to beveling and embossing, and the smoothness of it. It gives you a lot of control, allowing you to create the exact look you’re going for. And of course it’s entirely adjustable, allowing you to continue to refine once you’ve already started.
Now if you have a flat texture, something like metal or plastic, and you want to add some lines for detail, nDo has you covered there too. You can activate nDo on a blank layer and paint symbols or lines, then convert that into normal map information. It’s a very advanced tool that even a novice can use.
What’s especially great about nDo is that it’s completely free, which is very useful for students, indie companies, or even portfolio work. I used it myself on personal models for my portfolio. In the example image, I converted a stone texture into a normal map with nDo for a few NOS tanks on a sci-fi gun I designed. The texture gave a rusty metal band a worn, weathered look. The painted bolt above the tanks was given detail with nDo as well.