Havok

[Munro]

Havok physics is at the heart of the eagerly awaited Half Life 2 from Valve Software.
Physics gameplay is considered one of the key new departures in the sequel and is
an integral part of the game experience.[br]
[br]
Halflife2.net: How was your relationship with Valve during the development
of Half-Life 2? Do you plan on working with them in the future?

Havok: Valve were one of the earliest users of our technology, and were
able to give us great feedback throughout their development of Half-Life2. They
really understood what it could do, and its limitations. With Valve’s input, for
example, we completely re-implemented our constraints system. We certainly hope
to continue working with Valve.

Halflife2.net: How long did it take to develop the Havok 2 Engine?

Havok: The Havok 2 engine is simply the latest iteration of our physics
engine. Development started on our physics as early as 1999, and we have been
refining / rewriting parts of it ever since based on the feedback from our customers.
Our product development team has had approximately 10 engineers working on the
core physics for the last 4 years.

Halflife2.net: Was Havok 2 developed primarily for games? Or did you have
other purposes in mind?

Havok: Havok 2 was developed as a games solution from the start. The design
decisions we took during its development were all based on this assumption. For
example, wherever we can get away with it we will happily sacrifice accuracy for
speed. Havok is used outside of games though – for example the team responsible
for the Burly Brawl scene in Matrix Reloaded used Havok to pre-visualize and simulate
the motion of the Agent Smiths.

Halflife2.net: Did you have to change/add anything in the engine specifically
for Valve?

Havok: Sure. We listen carefully to what our customers tell us because
ultimately it’s about the game and how fun / cool it is. For Valve, for example,
we did extra work on constraints (improved the ragdoll simulation).

Halflife2.net: Is there any truth to the rumours of legal issues between
yourself and Valve?

Havok: I don’t know what the rumours are, but our relationship with Valve
has always been a good one.

Halflife2.net: What makes the Havok engine itself unique (other than the
games that use it)?

Havok: Well, the games that use it are the key to why the engine is unique.
Every time we’re used in a game by one of our clients the engine improves further
based on the feedback from the client. We’re now in over 100 games – that’s a
lot of games experience that’s built into the engine. Sure, we could talk about
features and performance and all that but ultimately the most important thing
is: does Havok understand what it takes to make game physics work? We’re still
learning but we’ve more experience of this than any other provider out there.

Halflife2.net: How many full time engineers work for Havok? What is the breakdown
in terms of education, e.g., how many have Bachelors degrees, how many have advanced
degrees? What would you look for in a programmer if they applied for a job?

Havok: There are currently 26 full time engineers working for Havok all
with Bachelor Degrees, mostly in computer science, computer engineering, or mathematics.
We have PhDs and Masters degrees too (but none of these were in physics). You
don’t need to have a higher degree in physics to work on a physics engine. We
look for people with a love of programming, who get stuff done, and get as excited
as we get about what we do.

Halflife2.net: Did the release of the stolen files from Valve have any effect
on Havok (the company and/or the engine)

Havok: Like everyone else, we double and triple checked all our own security
measures – that’s about it.

Halflife2.net: What are your plans to advance your character animation technology
in the future? Do you plan to move beyond ragdoll physics and support full physics
based character simulation?

Havok: I think ragdoll physics are starting to become quite commonplace,
especially in first person shooters. With our help, our clients are starting to
go beyond the common ragdoll effects you see in games today. We’re looking at
more realistic ragdoll modelling, and also how to expose the power of the ragdoll
simulation to the character animators to give them much more control over the
dynamics.

Halflife2.net: Have your engineers been working on real-time fluid dynamics
for smoke/gaseous effects, and/or water? If so, how can these effects can enhance
gameplay for both casual and hardcore gamers? If not, are fluids on the agenda for
future versions? Is there any chance we'll see them in the near future?

Havok: We have looked at these in the past, but nobody we have worked with
has really come up with a good way to incorporate these into gameplay, with the
possible exception of the use of a simple buoyancy effect.[br]
We are only just coming into a time where physics is being used generally by games
to enhance gameplay. I think in the near future we will see this become more prevalent,
as game designers start to explore the possibilities physics presents more.

Halflife2.net: Does the Havok engine have any sort of support for sound simulation,
i.e supporting sound dynamics and interaction, superposition, etc. of sound waves
with other objects? And if not, how easily it would be to implement into the Havok
engine?

Havok: We don’t simulate anywhere near the frequency needed to synthesise
sound, so we don’t do wave superposition etc. For details of what you can achieve,
you should see Brian Sharpe’s (from Ion Storm) talk at GDC this year. They have
been using the Havok engine as the basis for physically based sound effects.

Halflife2.net: How many lines of code is the engine?

Havok: That depends – on what platform? Do you count assembly / microcode?
Do you count the tools used to create content, or the debuggers…? Lines of code
are somewhat meaningless as a metric – remember that on consoles in particular
we try to keep the engine as small as possible because of the limited memory of
those systems. We’re an embedded software component, so we have to be fast, tight,
efficient and robust.

Halflife2.net: Do you plan on supporting the Independent Game Developers
in some way? Offering the Havok 1 engine for a low price or by designing a separate
engine for Indy developers possibly?

Havok: Hey, we’d love to. We’re all indy developers at heart!! But, all
our resources are focussed on delivering good software and fantastic support to
our clients to help them deliver games. So right now we’ve no plans this.

Halflife2.net: To what extent can mod developers change or modify the Havok
settings/engine?

Havok: This is up to Valve, They choose what level of functionality to
expose. The physics will of course be customizable and tweakable but Valve have
worked hard to make sure it is as easy as possible to harness the creative potential
of the physics. We’re incredibly excited to see what the mod guys are going to
create with the Half Life 2 engine.

Thank you to those at Havok for spending the time to answer these questions.