I’m a keen advocate of seamless bitmap textures. These play an essential role in the production of 3D models, as I described last month, but are just as useful in 2D work – applying a simple tiled bitmap can instantly bring a flat image to life. Nothing beats texturing for maximum impact with minimal effort, so long as you have the appropriate one to hand. But that’s the problem: you can build a library of naturalistic and abstract bitmaps downloaded from the web or provided with applications (I’d download the free trials of Piranesi, SketchUp and Real-Draw PRO just for the samples), but however many you have it’s never enough.
Say you want to apply wood texture to a rectangular plane to create a realistic floor: if you’re very lucky, you might have the perfect one ready to wear, but more often it won’t be quite what you require. It might just need the colours tweaking, which you could do in a bitmap editor, but there’s more to realistic wood texture than just colour – different grains, knots, densities and so on – and if you’re talking floorboards or parquet there’s length, width, depth and placement, too. Worse still, you might have the perfect image but at a fixed resolution that’s wrong for the job in hand. Use it too close to the camera in a 3D image, or in too large a 2D print, and that blurred or pixelated wood texture will degrade your image and highlight its artificiality.
The solution is to create texture tiles yourself, which lets you choose the desired resolution from the start and take complete control of the end result. So how do you go about creating a bitmap texture? I’ve looked at this subject in previous columns, where I uncovered two real software gems, but both of these now offer so much more functionality that they’re well worth a fresh look.
The first of these gems is Texture Maker (free trial on this month’s cover disc, or download from www.texturemaker.com). When you first click on File | New in Texture Maker, you’ll be invited to define your tile’s final resolution, so make sure it’s more than enough for your intended use, but not so excessive it wastes memory and processing time. In most bitmap applications, once you’ve created a canvas you’d start applying paint, but in Texture Maker you instead apply a “function” – a formula that mathematically determines the value of every pixel in the bitmap.
It makes sense to start with the simplest functions, which are provided in the Basic category of Texture Maker’s Function Selection panel. For example, with the simplest Solid function selected, you can choose a shape from the Masks panel and apply a flat colour to it. Things soon become more powerful and more complicated, though. Select the Glow Fill preset and you’ll see that various changes have been made to the numerous panel parameters. The colour has been set to “white”, the mask mode to “fill”, the mixing mode to “add” and the modify procedure to “invert if > 0”. If you now click on that coloured shape you just made, it will be given a white border that fades so as to give a bevelled glow effect. Other presets with very different effects include Drop Shadow, Darken Binary, Fire Ellipse, Colorize and Structurize, and that’s all for the simplest Basic | Solid function! Texture Maker’s real power is to be found in its more advanced functions, of which there are 130.
Thankfully, all these functions are clearly divided into categories, and most come with presets (over 700 in total) that quickly give you an idea of what effects are possible. So how would you produce the wooden floor texture I mentioned earlier? Most textures start life as one of Texture Maker’s vast array of Generator functions, which include textures as diverse as Blobs, Bricks, Flagstones, Grid, Marble, Scales, Star Field, Veins and Water. There are two separate Wood functions, both of which use a customisable noise and gradient mapper to create the desired ring-based grain. Both functions also employ a seed value that by default changes randomly, so every time you reapply the function it automatically creates a new variation.