Update, April 10th: Use of some of the mateirals processing capabilities – notably Alpha Masking and Emissive Masks – can have a significant affect on Land Impact valuse – see my week 14 SL projects update for details.
On Monday April 8th, Linden Lab released the first public cut of the Materials Processing project viewer. As the server-side of the materials processing support was deployed to the main grid earlier in the year, this release means that materials processing – with some caveats – can be experimented with by all.
These caveats are that the viewer is still very much an alpha release, and as such is both subject to change and should not be relied upon as a primary viewer for everyday use in SL. Also, as elements of the viewer may change before it reaches a release status, it is viewed as advisable by LL that people do not use the materials capabilities on MOD / NO COPY items.
So how does it all work? I provided an introduction to materials processing as it applies to Second Life back in 2012. However, the following will hopefully provide a summary for those who haven’t kept up with the news as well as providing a look at the viewer itself.
What is Materials Processing?
Materials processing is the combining of various computer graphics “maps” to significantly increase the level of detail that appears on any object or surface within a computer game. Within Second Life, textures (themselves a form of computer graphics map called a “diffuse map”) are used to add detail to in-world objects and surfaces. The new materials processing capability will introduce two further kinds of computer graphics map – normal and specular – to Second Life which can be used alongside textures to dramatically increase the detail and realism of objects and surfaces.
- Normal maps are a means of faking high levels of detail on an otherwise bland surface by means of simulating the bumps and dips that create the detail. Normal maps can be created in several ways – such as from a texture (diffuse) map using a suitable graphics application (and plugin, if required), or by producing a high-quality model (mesh) and using an overlay process to generate a normal map which can then be applied to a lower-quality model of the same object (i.e. one with a lower triangle count) to simulate the same level of detail as the high quality model, as shown below.
- In the real world, every highlight we see in an object is actually the reflection of a light source. Surfaces reflect light differently to one another, depending on a range of factors (material, lighting source point(s), etc.). Specular maps simulate this by allowing individual pixels in an object to have different levels of brightness applied to them, giving the appearance of different levels of light being reflected by different points on the object. Like normal maps, specular maps can be produced in a number of ways, both within 3D graphics modelling programs and in tools like PhotoShop.
The new capabilities in Second Life allow diffuse (texture), normal and / or specular maps to be applied to in-world objects (prims, meshes), to achieve a much greater level of realism in their appearance.
First, Create Your Maps
In order to use the new capabilities, you must obviously have the required maps. These ca be created in numerous ways, and I’m certainly not qualified enough to give a hands-on demonstration myself. As such the following are intended merely as possible pointers.
Normal maps can be readily produced directly from an associated diffuse (texture map), which may be the most common way to do so. Both Photoshop and Gimp, for example, support normal map creation in this way, each using a suitable plugin. Photoshop uses the nVidia normal map filter for example, while Gimp uses a plugin of its own. There are numerous tutorials available on YouTube explaining how to create normal maps using either Gimp or Photoshop and these plugins.
As a user of Gimp, I found the following tutorial by vscorpianc provides a sold look at getting going with normal map creation, as it covers installing the required Gimp plug-in and also offers-up various resources for image files to play with, if you don’t have anything suitable yourself.
For those working with mesh, there are also various ways in which to produce a suitable normal map – including, as mentioned above, using an overlay from a high-quality model on an identical model of lower quality. Again, as I don’t use the likes of Blender, Maya, et al, You Tube offers what appears to be some easy-to follow tutorials for those who need them.
The same is true for producing specular maps within various graphics applications as well – such as bond1TGC’s tutorial on Specular Map Creation Tutorial or Aleks Markelj’s detailed tutorial Using Photoshop to create Diffuse/Specular Maps.
Inara Pey: Living in a Modemworld 