Quote:Original post by Ignifex
Often enough, graphics programmers overlook the importance of a realistic and artistically correct scene to show off their rendering techniques. I'm sure you're also familiar with the engines showing parallax mapping on a brick wall, where the texturemapping is done so poorly that the seams between the faces ruin the realism of the effect. And for most scenes, the BRDF and lighting parameters are also determined by the artist.

It depends on the type of engine you work on and your what you are ultimately trying to achieve.

In a physically based engine, the artist doesn't have a lot of control over the process. The designer is nearer to a technician or engineer than to an artist. Everything is entirely guided by physical laws. For example, while the designer can choose a granite BRDF or a glossy plastic, he cannot freely change the specular colour, the transparency or the Fresnel terms. All that is strictly enforced by energy preserving shaders. Instead, he controls surface roughness and absorbency, dielectric versus conducting surfaces, IOR, etc. He also cannot create lighting environments that are physically impossible. Virtual lights, for example, are popular to quickly 'fix' lighting that doesn't match an artists vision. However, it is not physically correct, and will not be allowed in a physically based modeling approach. Also, incorrect texture choices that often give such a weird look to programmer art are not really possible in such a system. All textures have to be in calibrated sRGB or linear space. So at worst, a surface can look out of place or bad taste, but it will never look unrealistic.

All that limits the freedom of the artist, and that's why a lot of artists resist such a production pipeline. However, it almost guarantees a photorealistic result, regardless of what the artist does. You can create a wooden rectangle, place stone teapots all over it, and the result will look like a photograph of stone teapots on a wooden floor. Although quite surreal, it will look perfectly realistic. I personally really like such a physically based approach, because it limits some artists tendencies to go overboard.

The other extreme is an entirely artistic design concept. Here, the artist has full control over everything. While this leaves him complete freedom, it is very, very hard to create photorealistic graphics with this approach. Unless the artist voluntarily adheres to the strict physical limits outlined above, the renderings produced by this type of CG often have a cartoony look. Which might be the intended effect, of course.

Quote:Original post by Ignifex
I agree with you though. :) But don't overlook the importance of a cleverly sculpted model or proper material settings, especially for real time applications.

Entirely physically based systems are possible in real time, except for fully dynamic GI. Now, in order to get a pleasing visual result, modeling and surface choices are obviously very important. But they shifted from "artistic freedom" to "engineered precision", so to say. As an example, an interior architect could select materials based on his real life experience, without any knowledge about 3D modeling or design, and still get excellent results.

All this is not so relevant for games, because here the artistic freedom is often a main selling point. However such physically based systems are definitely the future in other visualization sectors, such as architecture.