T w e n t y S i d e d

Normal mapping is the next step. It’s been a mainstay of AAA graphics since 2004A banner year for technology. Both Half-Life 2 and Doom 3 happened that year. While they weren’t the first games to do it, both were really great showcases for normal-mapping. and is one of the rare effects that I think justifies the horsepower that goes into it. I’ve never been stunned by depth of field effects, fullscreen anti-aliasing, or a lot of the other fancy-pants effects that required a new graphics card generation just for a bit of “Hm. That’s cool I guess.” visual flair. But normal mapping? Normal mapping is an honestly clever technique that solves all kind of problems.

In the past I’ve sloppily used the terms “bump map” and “normal map” interchangeably. I’ve always disliked talking about “normal maps” when doing these non-technical writeups because I didn’t want to have to stop every time and explain what a “surface normal” was. Without clarification, the reader is likely to assume a “normal map” has something to do with making things appear normal. Perhaps there are abnormal maps? The term “bump map” is just easier for the reader to graspAlso because I used to get them mixed up all the time. Nothing is better at helping you nail down concepts like having to explain them to someone else..

But now we’re working directly with the concept, so after committing years of sloppy terminology abuse we’re going to make an effort to get things right.

I’ve explained normals recently, so go read that if you want the long explanation.

So the problem is that we want worlds with lots of detail. If Gordon Freeman walks up to a wall, we expect the bricks on that wall to look 3D. If a light is shining down the wall, it should strike the tops of the bricks and not the underside. But we don’t want to have our artists build thousands and thousands of bricks just to create a simple room. Even if the graphics hardware can handle drawing them, that’s still not a great use of artist time. And even if we had unlimited artists, it would be incredibly difficult to have each and every room in the game contain Pixar-levels of extreme detailActually, a full-poly scene in a videogame would be WORSE than the same scene in a Pixar-type movie. In a movie, the author controls the camera and you can cut corners on the stuff that isn’t viewed up close. In a game, the audience controls the camera so EVERYTHING has to be high detail. for every element in the scene. Even if development costs and rendering power are infinite, you still have to worry about distributing the game, load times, physics systems, memory usage, and a dozen other things that prevent us from solving every problem with MOAR POLYGONZ!

Continue reading ⟩⟩ “Project Unearth Part 3: Relief Picture”

Shamus Young is a programmer, an author, and nearly a composer. He works on this site full time. If you'd like to support him, you can do so via Patreon or PayPal.

You know what they say about when you assume something? When you assume, you might save time by using extrapolated information and pattern recognition to quickly zero in on the solution to the problem. No? That’s not what people say about making assumptions? I just kind of assumed people would… oh.

Well, my assumptions did in fact make an ass of meBut not you. You’re still cool. this time. I’ve read about various shadow techniques and I thought I had a decent handle on what I wanted to do. So when I read up on the theory I got to the halfway point and was like, “Yeah, yeah. I got this,” and started skimming.

Like many 3D concepts, this one begins with a crappy diagram:

Continue reading ⟩⟩ “Project Unearth Part 2: Skimming Hazzard”

Shamus Young is a programmer, an author, and nearly a composer. He works on this site full time. If you'd like to support him, you can do so via Patreon or PayPal.