MEASURED RESPONSE
There are at least a thousand cars in
the general Forza library, and Turn 10
has researched as many of them as
possible, taking them apart and
measuring the components. But what
if they can’t get access to a car? “If
you think about a car from the 1960s,
where there’s only three of them and
they cost $30 million, the owners
aren’t gonna let us take their car
apart and measure every bit with
calipers,” says Greenawalt. “I mean,
we’d like to. If you drive your car up
here, we will disassemble it and
measure it. But with a 1965 Ferrari
GTO that’s much harder to do.”
Instead the designers at Turn 10
will research other cars with the
same components, and if there’s
something they can’t measure they’ll
make an educated guess and fill in
the blanks. “It’s like Jurassic Park,”
explains Greenawalt. “Filling in the
DNA with other creatures. We want
our data to be as accurate as possible
and if there’s guesstimate data, we’ll
mark it in the system so if we ever
have access to that car in the future
we can replace it with the real data.”
But cars are more than data, right?
When you drive one, you feel
something. I ask Greenawalt how
Turn 10 captures the essence of a car
as well as the cold, hard facts. “If we
get the physics absolutely right, the
emotion will come out of it,” he says.
“A car doesn’t have any real emotion.
It has beautiful design, but that’s the
rendering. The curve of a Ferrari
with its Pantone red. That creates an
emotional response. But the way it
performs? That’s physics. So instead
of trying to hand-tune the cars in
Forza, we just rely on the data. If we
improve our simulation, the true
nature of the car comes out in the
physics itself.”moment of inertia really makes them
understeer like crazy. And this makes
things like drifting difficult, because
you can’t recover very well.”
But when designing Forza,
Greenawalt and his team decided
that the moment of inertia was
sacred and should never be touched.
“To make our cars feel controllable
and heavy, we have two main
strategies. One is the buffer we put
on the analogue stick. Depending on
how quickly you move the stick, and
how much you move it, you’ll never
get your full input immediately.
“We tune this based on how we’ve
seen players play. People generally
return to centre quicker than they
go out from the centre, so we have
unique buffers tuned in there.
“The other strategy is
having clamps and scales on
how much yaw, which is
the torque of the car, can
be applied to the
spinning skater.
Using these clamps,
we can slow a car
down without changing the moment
of inertia. When you play with
simulation steering you turn this
feature off, as well as a lot of
the buffers, but even I have trouble
playing Forza like this with a
[gamepad’s] thumbstick.”
I’ve never driven a Lamborghini
Sesto Elemento or an Acura NSX, but
what I love about Forza is how it
makes me feel like I have. I ask
Greenawalt how Turn 10 translates
the feeling of driving a real car to its
digital counterpart. “It all starts with
data, data, data,” he says.
“We send extensive data requests
to the manufacturers. But sometimes
they don’t know what we need to
know about the car, so we go and do
our own research on the components
that go into it.
“The transmission on a Mustang
is made by Tremec, so we’ll go to
them and find out about the inertia
on the gears and the weight of the
gearbox, rather than going to Ford.
“Our goal is to have future proof
data, and the simulation will catch up
with this perfect data and become
betterasa result.”BOTTOM: Lavishly
detailed interiors like
this are an example of
how deep Forza’s
detail goes.
MAIN: Developer
Turn 10 works with
the world’s best car
and parts
manufacturers.Forza Motorsport
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