Extreme SIMD: Optimized Collision Detection in Titanfall

In this 2018 GDC talk, Respawn Entertainment's Earl Hammon explains how the Titanfall team made already optimized continuous collision detection code more than twice as fast.
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[@log0las]

From "Yeah I know what an AABB is" to "I don't understand shit" in 10 minutes

[@ChamplooMusashi]

Ah another video that will take an hour to watch and a year to understand how to implement

[@djmips]

So how did the implementation go😅?

[@-Engineering01-]

​@@djmips i think it takes more 😂

[@edwinontiveros8701]

@@djmips it's on pre-alpha, ready for release. I'll patch it on the go.

[@besknighter]

Wow. What he says about this and Mike Acton says about Data-Oriented Design is what the "Computer Engineer" mindset and knowledge should be about. I want my tuition back.

[@TotalControlVR]

I'm a simple man, I see "extreme SIMD" and I click

[@boiboi7717]

men only want one thing and freaking disgusting:

[@paulcosta8297]

Legendary comment

[@torphedo6286]

From what little I comprehend, this is beautiful and terrifying. Definitely going to have rewatch this many times to understand it, it's nice to be humbled by such insane micro-optimization.

[@Maouww]

Oh my gosh. I only understand like 50% of this but even the stuff I understand is SO GENIUS and answers a few problems I've had.

[@Maouww]

for those confused at 14:26 - he said leaves and nodes the wrong way around (read the slides)

[@testsubject3810]

He looks exactly how I imagined a man named Earl would look. Excellent talk Earl!

[@tlacmen]

I like the words firster and laster :D The whole presentation is very professional, full of really neat tricks, and keeps viewers fresh with many nice puns.

[@theIpatix]

Although I have to admit that I could not fully understand everything, this is a really cool talk. I'll probably come back to it once I have a good use for all these neat tricks!

[@GonziHere]

Nice, Will have to rewatch for the parts that were too much for me, but I absolutely loved it. Thanks.

[@Giraffinator]

I have no clue what's going on here, I'm just thirsty for more Titanfall content

[@Chemia1234]

Great talk! ...some introduction to AABB/SAH: "Physics for Game Programmers: Spatial Data Structures" by Gino van den Bergen

[@yowhat3745]

Can you provide a link?

[@Anakom23]

Well, I watched that video 8th time (during almost 3 years. damn I need a counter). A year ago I thought that I got most of what is done here. Yesterday I had an existential crisis, because I don't understand how much I don't understand in this video. I currently implementing collision detection system, and thought it would be cool to implement techniques from here. Boi I was not prepared. See you in few months. Hopefully I will make beautiful trees XD

[@theIpatix]

50:32 Lol, "case where octal is actuall useful" :D

[@ashwanishahrawat4607]

I found my brain in fragments after watching this video complete, For some strange reason, i want to redo my whole game engine. :|

[@Jarmundx]

Well... You did watch a GDC talk from a veteran game programmer

[@alariq]

was a bit-confused after watching it. great stuff

[@ViralWatchMedia]

I was lucky enough to know one of the lead programmers Steve Marton before he left respawn some years ago. I was an unofficial beta tester for some of the early patches for the PC version of the game. I have to say it was really cool being able to work side-by-side with the developers on fixing some of the issues with the PC version on release. if you guys are wondering basically I'm one of the guys who really helped the team nail down what was causing the stutter issues. P.S. it had to do with some poor Vram swapping where old texture data wasn't dumped causing the game to make the GPU's on board Vram to work overtime swapping out the old textures with new ones causing a bottleneck on the texture streaming budget.

[@DevGods]

Anybody else's brain hurt? And bro allergies was beating his ass lmao.

[@daveyhu]

Neat talk! Have to admit I got lost about 20 minutes in, maybe some more explanatory drawings would've helped. Very cool trick wrt floats and div by zero, did not know that's how it worked.

[@smartties]

Interesting talk, I would love another talk about Physics in multiplayer games where players can impact physics of other players (Prediction/reconciliation) like in Fall Guys

[@yasserarguelles6117]

I've been making a similar system for my Arena FPS, but I'm interested in how other people do this. Great vid

[@niks660097]

writing SIMD code yourself is not a good idea? better use some library/low-level framework for that..

[@samuelschwager]

I'm one of the 1% people. I've understood about 1% of this ;)

[@Miki19910723]

This guy is on another level ❤

[@megac0ffee]

I don't understand how we can skip the face test if the center is outside the 3 planes. That works if the triangle's plane is orthogonal to the query direction, but imagine a triangle almost parallel to it. The sphere can be contacting the face and yet the center, from the viewpoint of the query, will be outside the extruded edges.

[@Flourish38]

It works because you also expand the edges by the radius of the sphere in the projection space. That means it works even if the triangle is completely parallel to the ray.

[@unveil7762]

Yeah collision was well done. Sadly the game got no updates… and the mission was near to impossible to accomplish… and get no updates… 60 euro on the trash THANKS anyway for the talk…. Can i have the code with this 60 euro i spent on the game ?? At least i can use this in my Project 😅

[@lanchanoinguyen2914]

Yeah a bullet goes through wall was a common thing,it sound like quantum physics.

[@nexovec]

11:30 What exactly does "evaluating the cost" mean here? Can someone explain please? Do I opt for the smallest sum of the two surface areas?

[@baileyharrison1030]

From what I've found online, and what I implemented, was to use ( ( box_1_surface_area * entities_in_box_1 ) + ( box_2_surface_area * entities_in_box_2 ) / previous_surface_area. Where 'previous_surface_area' is the area of the AABB of the parent node in the tree.

[@tommydrager5497]

its at the moment where you find other people describing the same ideas and techiques much simpler, when you realize that this presentation was actually pretty bad... but this guy is a great engineer not an entertainer or teacher.

[@scaltra6709]

I like your funny words programmer man

[@bhavinb.artstation]

Ikr same 😍

[@GeorgeTsiros]

poor guy, something irritates his everything

[@isharalakshan2036]

❤ ☺