There is an enormous transcript available of an interview with Half-Life 2 creators Valve over at Mod Database. The log contains a sizeable amount of information - mostly technical - on the abilities of the proprietary Source engine. We've picked through the log and presented a few of the less abbreviation-riddled technical facts; stuff that we thought was - for want of a better way to exude our feelings - cool.
On the recently released Traptown video:
"The blades cutting zombies in half is physics and AI as well. They've been modelled so they can be cut in half, but other than that they walk into the blades and the physics causes damage and they get split in half.
The zombie is aware of objects in the environment. His AI realizes when he can throw an object at you and applies the appropriate physics forces to make it happen. The zombies are not scripted to throw specific barrels; it's all tactical.
Were the I-beams and dumpster in the trap town demo scripted or physics + AI? They were all AI, we just hinted for the soldiers to stand in opportune spots so they could get smashed by the heavy physics objects."
On porting over Half-Life 1 modifications:
"Models, animations, and textures just need to be compiled with the new tools. The maps can be loaded into Hammer and saved in the new format (VMF). The code should be pretty familiar to Half-Life mod authors, but there is some porting of the code as some specific engine features are implemented differently usually - much more generally."
On crafting a Battlefield 1942 rip-off:
"A bunch of people have emailed me the following question: How would I use Source to create a BF1942-like game? Okay, here goes:
BF1942 has pretty large maps, so you'd probably want to scale your units down to allow for a multiple mile x mile playing field. We have some additions to our outdoor rendering, including a realtime occlusion system for dealing with issues unique to outdoor environments. We still maintain a BSP-tree based system for dealing with more traditional indoor environments. So, you can now do extremely large outdoor environments which seamlessly sic transition indoors. I'm excited to see the mods go nuts on this stuff."
On the new VGUI (in-game menus) systems:
"You can also draw 3d things into vgui panels so you can put a rotating model inside your menu. Also, you can have a vgui panel in your 3d world which you can manipulate so you can have an object in the world containing your menus, etc."
The guys went on to mention that the in-game console even has a web browser-style auto-complete feature to save on typing in commands. They've thought of everything!
"'How would I do cel shading with Source?' You would write your own vertex/pixel shader combination for a new custom shader and then use that shader in your materials that you want to be cel shaded."
And finally, Steam:
"'How can we use Steam to deliver card-specific resources?' We can deliver special versions of content to users with particular hardware based on the hardware that they have in their machines. Using this, you could conceivably make a mod that really pushes the limit of hardware and requires specific hardware to run. With the flexibility that you'll have with rendering, I could see mod makers go nuts with this." So can we, Gary. So can we.
Honestly, we wish we didn't know this stuff, just so that we could be blown away by it all over again when we find out about it in September. Wait, November. Wait... whenever. Anyway, if you're even slightly interested in what Valve has in store for us, the transcript makes for an interesting read, and there's an unedited version available here, which contains the details in context.
Oh and by the way - they've fixed anti-aliasing for all video cards