These images are intended to illustrate the point that you can tell a lot more about a surface from the way the light bounces off it, as the object, light source and viewer move relative to each other.
Basically, if you want a spaceship to look like it's got a metal hull, you should not be talking to your texture artist, you should be talking to the programmer responsible for the lighting engine. It's not that texture mapping isn't useful, it's just that it is so often used inappropriately. [bump mapping on the other hand can be very nice indeed]
So here is the same object lit and viewed from the same position, but with different surface properties to affect the way the lighting values are calculated. The first 3 images are direct screen captures from my rendering engine, the 4th and 5th are composites of 2 & 3 using standard Photoshop filters, which indicate the sort of effects a 3D programmer really should be experimenting with.
1. The object with standard diffuse light sourcing [btw - the windows and wing panels are 'shiny' but from this angle do not catch the light]
2. "Chalky" - surfaces facing the viewer have brightness attenuated
3. "Metallic" - surfaces facing away from viewer are attenuated. An extreme version of this effect looks less like metal and more like a white object covered with black fuzz
4. "Stealthy metal" - applying the difference filter to 2 & 3
5. "Solarizing metal" - applying the exclusion filter to 2 & 3
Thursday, May 15, 2003