25/Aug 2010
3 min. read
Quick idea I’ve had for a while, but likely won’t have time to try out, for getting rid of UV sets once and for all by just looking up textures with a 3D position.
Start with a coarse grained 3D hash grid (i.e a hash map of your grid cell coordinates), then each of these cells would represent, say, a 2563 volume texture indexed by your vertex position. For compression (this volume data would be extremely sparse, usually little more than a flat 2D slice through it), it would use 3D Random Access trees (read this if you haven’t heard about primal vs dual subdivision – eye opener for me!
22/Aug 2010
2 min. read
I’m generally unimpressed by specialized game courses at university. Generally I’d be more inclined to trust a traditional CS or CE degree with a strong side-interest in game programming over a specialized game course.
One of the problems is that many game courses either don’t teach any low-level programming at all, or teach it poorly.
Obviously we still all use C++, so it’s crucial that you understand low-level programming, and every so often you actually need to know it for real, and not just because the language is too low level for you (e.
11/Jul 2010
12 min. read
It’s been a couple of months since GDC, and I’ve been meaning to do a blog post about the talk I gave there (and if you have membership to the GDC vault you can even see a video).
An R-tree is a data structure for spatial indexing that’s optimized for out-of-core scenarios (basically databases). Spatial indexing is used for storing “stuff” in space. For example, a game might store all of the game objects in a spatial index so that we can efficiently query for things like “give me all objects that are within the view frustum”, or “give me all pairs of monsters and exploding barrels within 5m of each other”.
24/Apr 2010
5 min. read
Jonathan Blow is working on stable cascaded shadow maps, and trying to reduce wasted texels due to the way the shadow frustum is set up. Well, as it happens I have my own minor tweak to Valient’s technique that also reduces wastage, so I’ figured I’d describe it here with pretty pictures. I’m going to assume that you’re roughly familiar with the general idea, if not, read e.g. Blow’s first blog post on the topic, or ShaderX 6.
18/Apr 2010
11 min. read
As you may have heard, Direct X 11 brings tessellation support, and all the hardware vendors and benchmarks are going crazy with super-finely tessellated meshes, promising us automatic level of detail and unprecedented visual fidelity. What you may not be aware of is that the Xbox 360 has very similar tessellation hardware too, which means many game developers have had the opportunity to use these same techniques for about five years now.
22/Nov 2009
3 min. read
I just watched a panel from PDC called Microsoft Perspectives on the Future of Programming with loads of “big name” programming gurus. At the end of the session Herb Sutter points out that eventually Moore’s law will end, and then optimization will become extremely sexy again. This is a very good point, but I think there’s another law that will cause optimization to become sexy again far sooner than that: Almdahl’s law.
4/Jul 2009
9 min. read
Signed Distance Functions are a pretty simple concept. Basically for each point in the world, you return a distance to the nearest surface, negative distances are inside geometry. One neat application of them to represent scene geometry, and ray trace into the SDF. Why would anyone do such a thing? Well, it turns out that when marching along a ray looking for intersections (which is obviously not the only way to trace rays), it’s jolly useful to know a minimum bound on when you might expect to encounter a surface.
1/Jul 2009
3 min. read
A few days ago industry analyst Michael Pachter said the following:
The number of games traded annually is striking; we estimate the overall used game market to be $2 billion in the U.S., with an average ticket of around $20 per used game. This means that an estimated 100 million units of used games are traded in each year, representing around 1/3 of all games sold annually.
Blimey! That’s a lot of money, and what’s worse it’s money that goes directly into the pockets of retailers, you know the people who do not fund the development of games, and do not take any risks.
27/Jun 2009
5 min. read
A few years ago I watched TED talk by Peter Donnelly dealing with statistics, and in particular the prosecutor’s fallacy. You can view it here. This was a thoroughly enjoyable talk and I recommend everyone to watch it. However, it turns out that not even statisticians are immune to making this basic error, as this recent article by Bernd Beber and Alexandra Scacco about the probabilities of election fraud in Iran shows.
27/Jun 2009
5 min. read
A few years ago I watched TED talk by Peter Donnelly dealing with statistics, and in particular the prosecutor’s fallacy. You can view it here. This was a thoroughly enjoyable talk and I recommend everyone to watch it. However, it turns out that not even statisticians are immune to making this basic error, as this recent article by Bernd Beber and Alexandra Scacco about the probabilities of election fraud in Iran shows.
