Far Cry 3 – On tessellation, FOV and enjoyment

So I changed two minor video settings at some point this week and it’s like I’m playing an entirely different game.

I changed the geometry to ‘Ultra’, and the Field of Vision (FOV) to 90 degrees, up from the default 75. These two changes have literally flipped my experience of Far Cry 3 on its head. Before it felt like I was fighting against the game at every step, now I feel more ‘relaxed’ and at-east within the game, being able to inhabit the world much more fully.

Which seems bizarre, right? Two tiny settings and now I can enjoy the game, whereas before it was a pain? But it’s absolutely true. Lets talk about what these two settings actually do in detail and speculate around why they might be so important to my enjoyment.

So some important PC spec details:

  • Intel Core i5 2500K overclocked to ~4ghz
  • 8gb of (I think?) pretty fast timed RAM
  • 256gb SSD
  • Nvidia GTX560

Pretty powerful stuff that I shelled out for last year, should be able to handle pretty much whatever I throw at it reasonably well. But there’s a catch with the 560 and a particular DirectX 11 feature involving ‘tessellation’, which in a nutshell adds more triangles to more complex geometric objects as the viewer approaches them. Here’s the Nvidia ‘endless city’ demo that shows off this pretty neat piece of tech. Watch the following zoom-in/zoom-out section to see how it dynamically adds and subtracts geometric detail.

“If I zoom out you’ll see how all that simplifies, and if I zoom in more and more triangles come back.”

This is neat! It makes complex in-world objects look… well… complex! But there’s a catch. How do you render the addition of these triangles without it looking like the object is morphing before your eyes? The nVidia demo manages it because there’s a lot of shadowy darkness around it, and in the textureless and wireframe views we don’t notice the unrealism of the morphing because of the abstract nature of those views.

But in Far Cry 3 this technology is where the rubber hits the road, for me at least, as the method of smoothing between geometric levels of detail becomes painfully distracting. Essentially, a shimmer effect is applied over the object as detail levels are added or removed, and in complex scenes with a lot of dynamic addition and subtraction this gets overwhelming really fast.

Here’s as good an examples as I could find, watch the two crates/boxes besides the hut at the third place the camera swings around to after the player turns off the radio tower. I’ve set the time on the video as close as possible to the point. It may take some re-watching to see what I mean, and admittedly it doesn’t look that ‘bad’ here, but there are scenes where it has been incredibly distracting for me. (You’ll have to watch in 720p to even notice, but it’s plainly visible at 1080p)

It also happens on a basket sitting on the bench in the first scene, and on a flower in the bottom right corner of the second location the camera pans around to. Once you start noticing it, it can get distracting very quickly, and what has been seen cannot be unseen.

So what was the purpose of setting it to Ultra? Well the change that effects is to decrease the amount of culling of triangles, so once the high detail is there it generally stays till you are very far away, and (I think) you also begin to see the shimmer happen further away form you, reducing its impact. When the shimmer effect looks like an item is being beamed in by teleporter from the Starship Enterprise, it’s worth trying to minimise it as much as possible. So that change was something of a revelation.

The second change, to widen the FOV to 90 degrees rather than the default (even for widescreen!) of ~74/75 degrees felt reminiscent of the cessation of an irritating noise just below conscious attention. It was that kind of release of an ambient tension that is pent up just below the surface, the kind you are entirely unaware of until it actually lets up at which point you suddenly go “Wow, I was clenching my jaw without realising”.

Such a simple fix, and one I didn’t realise I was missing until it happened. What does this tell me about myself and what I am used to? I think it’s a sign that I have so habituated the ‘angle’ or ‘perspective’ that goes with a certain field of vision that I resist attempts to be squished into anything less. But this is strange, why would I feel so claustrophobic when constrained by something as simple as FOV?

The 90 degree FOV puts ‘your head’ further back from your arms, as a consequence of the bending it does to include more of the field of vision into the rectangle of your monitor. You end up ‘further away’ from your arms, as a result. This is a weird paradox because, as I said about Far Cry 2, it was my identification with my arms that caused me to feel like I was so much more a part of the world. In fact what I said about Far Cry 2 was that it wasn’t so much a first person shooter, as a first person hander. You ‘do’ most of your verbs with your hands in that game, heal with your hands, climb with your hands, swim with your hands, shoot with your hands (hands that very competently translate your instructions into weapon handling) but which are also interrupted by sick hands when you have to cough and splutter and take anti-malarials.

So in Far Cry 3 getting further away from my hands (and further ‘back’ from the screen perspectivally) ends up ‘feeling’ better, and along with a couple of the skills which allow me to (I think?) run faster generally, I feel more competent and confident at inhabiting the world.

How silly that such things depended on two little menu settings, and that it took me so long to realise.