Surface Solutions

What is a 'Surface Solution" map and how is it different from a bump map?

As you probably know, a bump map is usually an 8 bit grayscale image of an object or substance created to tell a rendering engine how far away from the viewer any given pixel in the image is supposed to be by using shades of gray to depict the pixel's elevation. Absolute white is closest to the viewer while pure black is farthest away with 254 more positions in between. While bump maps do a pretty fair job of enhancing the dimension and detail of an object, they have their limitations.

Bump maps treat this curved surface like a series of steps and display light reflecting in only one direction.	In the real world, a curved surface bounces light at a myriad of angles. Surface Solutions record that data to pass along to your renderer.

Bump maps can only contain information pertaining to the 'Z' index, or the direction directly toward viewer. In the real world, light bounces off an object in many directions, not just the one, but bump maps can't deal with information involving the 'x' and 'y' axes so information is either lost or interpreted in some other way. This isn't a bad thing, it simply could be better. Now it is!

The Surface Solution Map is an image in RGB that, like a bump map, contains all the information regarding the 'z' axis and also the 'x' and 'y!' So it is capable of recording and displaying the precise angle of light reflecting in any direction away from a surface. Surface Solutions are also 'edge enhanced' to produce finer, more accurate detail than that which can be achieved with other methods.

Surface Solutions have less of an impact upon the final rendered color, too! No matter how well made, a bump map is going to have a significant effect upon coloration in your final rendering. It will either lighten or darken your texture and this is seldom a desired effect. It's just something you've had to live with. That's changed, too!

This is really BIG news! and has great implications for you and your artwork. Now when you texture a curved surface, your renderer can depict it as curved instead of a series of steps, each reflecting light at a 90 degree angle. The result can only be a smoother, more natural and photorealistic rendering of any texture or object. So no matter what level of artistic skill you possess, Surface Solutions will improve your artwork dramatically!

In the examples below a leather texture shows the importance of reflecting light properly to achieving a natural appearance. Only the bump map and Surface Solution were changed in these samples, all other conditions are identical.

	This is the original color map rendered onto a sphere without bump enhancement of any sort.
	A bump map is used here at 25% strength. Note the overall coloration effect and the almost faceted coarseness of the grain. The appearance of this texture could probably be improved by spending some time tweaking, but then, why?
	The Surface Solution used at 25% gives a smoother, more supple and natural appearance to the leather by dealing with the grain as gentle curves instead of a ledge ridden terrain. Notice, also, that the coloration is much less affected.

There's gotta be a catch! What's the downside here?

Well, you're right. Nothing's perfect, but Surface Solutions are as close as it gets these days. If Surface Solutions have a weakness, it would be their file size which can be as much as three times the size of a comparable bump map (usually about double). This stands to reason, though, considering that a Surface Solution map contains a great deal more information about the surface over that which a bump map holds. Still, this is a very small disadvantage considering the savings that can be realized from less geometry.

You'll be seeing a lot of Surface Solutions from us in the days to come, so keep an eye out for them!

Copyright © 2004 M3 Corp., Inc.