What is the Procedural Generation of Textures ( Maps)

In 3D Modelling, 3D Texturing, Art by Christian Justamante Jacobs

In the world of computer graphics, game development, etc a texture is when you represent the appearance of the surface digitally. Nowadays, the advances in technology allow the generation of these textures to use mathematical parameters instead of the traditional method of placing those textures manually by the coders.

So, what are procedural textures?

Basically, are textures, also called maps, generated in an algorithmic way by employing mathematical descriptions instead of relying on some stored data.

The process by which this digital representation is done is referred to as a procedural generation. To explain simply, the word procedural is defined as the process that computes or brings about a particular function or activity.

Granted, there are sets of parameters given to work with in procedural texture generators that enable the computer to anticipate the kind of result the user is expecting. Nonetheless, it is also possible for a user to design a generator from ground up; needless to say that the process may be cumbersome –requiring time and vast knowledge in coding. It saves you time when you find a generator created by another user online as long as you are taken up to speed with relevant information regarding how to use it.

At the mention of the word ‘texture’ –as most people think –what comes to their mind is an image used to ‘paint’ a certain surface or object in order to give it a unique appearance. This is often called bitmapped textures mainly as a result of the texture being made of pixels that emanate from a real bitmap image.

Understanding Bitmap textures

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Note that the resulting image mostly appears to be ‘real’ –more likely–when captured from photographs of real surfaces. Whilst this is the case; do have it in mind that there is a major restriction that applies to all bitmapped textures and this is the underlying truth that bitmapped texture has a firm or fixed amount of detail. To this end, it is literally impossible to scale larger without appearing softer. What this means is that it won’t yield any further detail other than what is initially captured in the pixels.

As it is today, it does seem that procedural textures are a whole new game in itself as it takes an entirely different approach. Now instead of putting out an image by creating a big; fixed block of pixels –procedurals build up the texture from scratch. This process explains how the term ‘procedural’ came about. The texture is defined mainly by the required procedure to form it. By virtue of this; a relatively simple formula is all you might need to input in your computer instead of some huge block of pixels. The formula would enable the computer to build the texture at any scale based on preferred orientation and it could stretch as far as you want.

Procedural Texture: The Journey so far

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It cannot be denied that the world seems to have moved into a new age for procedural texturing. We are now in an era where these digital techniques are –not only –fascinating to those who have theoretical interest in it or those who engage with it such as 3D artists. The interest in procedural texturing has cut across a wide range of audiences. It has moved beyond those who first gave this digital representation technique a home; the highend game development studios, animation, and VFX.

As the gear hits higher, the use of procedural algorithms to create textures –considering its current acceptability and presence –are only going to grow by leaps and bounds in the coming years.

Procedural techniques can be easy to use. It is considered to be relatively simple to apply; reason being that it does not require mapping in a ‘special’ way. Nonetheless, this does not suggest -out-rightly –that procedural texturing cannot become complex.

Procedural texturing may not be better explained without drawing a link with texture mapping.

What is Texture mapping?

Texture mapping, in computer graphics or game development, is a design process that allows two-dimensional surfaces –also known as –texture map to be wrapped around or buried in a three-dimensional object. This process enables the 3-D object to birth a surface texture in the likelihood of the 2-D surface but enhanced.

Now when you think of applying a veneer, paint or wallpaper to an actual object; texture mapping offers you the electronic equivalent of that activity. It should go without saying that when you map a 2-D surface directly on a 3-D rendition, the process alters the shapes and sizes of the image elements.

Some of the obvious differences between a 2-D procedural texture and 3-D’s are noticed in the color information. You would discover in 2-D texture that the color information is defined by two dimensions whereas the one for 3-D texture is exemplified by its three dimensions’ manifestation. The nature of the color information in three dimensions is what makes 3D texture to be particularly effective; especially in situations where the texture needs to add color to irregular shapes vis-à-vis 3 D volumes. You can think of these examples; rocks, smoke, rubble etc. [basically] objects with obvious gaps and/or objects with irregular shapes.

On the other hand, this may be impossible with 2-D reason being that it has no 3-D information; this means the color information will stay unchanged in the face of 3-D rendition. However, the process usually results in stripped surfaces that are perpendicular to the direction of the projected 2-D texture; eventually looking like an overstretched texture across the surface.

In addition, the properties of a 3-D textures can be doctored in such a way that it alters the appearance of the texture. This may be impossible in 2-D procedural textures. One could easily say that the foremost reason why 3-D procedural textures are used for more complex materials is that its settings are found to also contain texture information.

Benefits of Procedural Textures

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Below might not necessarily be an all-encompassing list but should be good enough to let you have an incline into some of its pros and perceived cons.

The most obvious benefit is having the computer do on your behalf all the difficult job on textures making. It makes it totally easy! It should be noted that there is no fixed or permanent texture size, this suggests that users are allowed to make resolution changes to whatever they need. This is considered useful especially when a user is generating a high-resolution rendition that will be expanded on a billboard and/or used in many other mediums and platforms.

Procedural textures are particularly good for creating noise maps at random. Randomized noise map. This enables users to easily generate rough surfaces when needed by applying reflective and bump maps in their projects. Most of the contemporary 3 D packages offer the ability to create these non-complex procedural maps; which then suggest how easy they are to access.

Procedural textures can allow –in a timely fashion –a faster workflow duplication. Though, we should recon with the initial cost of generation; referring to the process of material creation after which iteration becomes faster.

Granted, procedural texture appears to be flexible. It gives room for users to modify texture being created. The aftermath of this is that it offers you the chance to generate entirely different images.

On the other hand, there are a few things regarding procedural textures that may be perceived as drawbacks for some users. These include:

1. It would seem like creating procedural textures at the start, though understandably, take a longer time than it is when loading them.

2. Also noted is the fact that it does appear to be difficult to design a formula that’d offer you the actual appearance you desire. Ultimately, it might just be easier to have an artist generate the texture.

3. Creating procedural textures with mastery can gulp some huge number of instructions, particularly ‘shader program’s’. And when faced with an option to pick from pre-made textures, without doubt, building from the ground up will almost always be time-consuming.

In a Nutshell

Procedural texturing is a very common digital technique application that is used to add details or enhance the surface of a material or an object. It could be said to be a method of defining the surface properties at every point whilst having in mind the desire to give the ‘outlook’ of the surface some added details that might not be present in the actual surface.

Meanwhile, implicit procedural methods –in the texturing space –are believed to be the best for textures; particularly those evaluated during rendition. Likewise, texture samples –in both depth buffer renderers and ray tracers –must be evaluated in an array/order chosen by the renderer and not, as the case may be, by the texture procedure.

Ultimately, procedural textures are a great addition to the three-dimensional workflow because they make texturing regular surfaces and objects a walk in the pack; also enabling automation to relatively save time.

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About the author: Christian Justamante is a professional 3d artist working in Elite3D creating characters and assets for the video game industry. His knowledge in 3D makes him an expert in 3DSMax, Maya, Zbrush, Substance Painter, Marvelous Designer, and other similar programs.