For example in forza, the game plays engine sounds based on how much we press the button. Are there different sequences of clips ? If yes how do they blend so well ? Or are they synthesized dynamically ?

There are so many parts to it as well - when the gear shifts, when you suddenly slow down at high speed, when you suddenly accelerate from stop. They all seem very realistic.

Edit: Thanks for the great answers everyone 🙏

  • otacon239@feddit.de
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    5 months ago

    Most older games will have 2-3 engine loops that they will blend between and pitch accordingly, however Forza 5 specifically was the first in the series to use granular synthesis which is a much more modern approach.

    These will have a series of sound files including all the different parts of the engine, exhaust, turbo, etc. Then the software slices these files into tons of pieces in real-time and plays the slices based on the players inputs.

    It’s tricky to explain without examples, so here’s a video that does a decent job of explaining how it works in music: https://youtu.be/ftDLRYnRYZQ?si=SEHOl55K7rimi4Eu

    • GamingChairModel@lemmy.world
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      5 months ago

      Some electric BMWs do the same on the literal automobile, too. It’s an EV that sounds like a high performance ICE both inside and outside the car.

  • Ephera@lemmy.ml
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    5 months ago

    It’s certainly simpler than Forza et al, but there’s an open-source racing simulator, called Speed Dreams: https://www.speed-dreams.net/
    If you watch the “Latest Release” video, there’s some engine sounds in that.

    They seem to have a bunch of samples for how different car models’ engines sound: https://sourceforge.net/p/speed-dreams/code/HEAD/tree/tags/2.3.0/data/data/sound/

    And then they modulate that in code, based on the car’s speed, gear, turbo etc.:
    https://sourceforge.net/p/speed-dreams/code/HEAD/tree/tags/2.3.0/src/modules/sound/snddefault/CarSoundData.cpp#l171

    They also do that for gear changes, tyre sounds, collisions and backfires.

    From what I know about audio, I would expect AAA games to still use the same approach of recordings+modulations.
    While it is possible to fully synthesize an engine sound, it doesn’t help you much with making it sound right in all different situations.

  • Tarquinn2049@lemmy.world
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    5 months ago

    Nowadays, it is exactly as complex as it sounds. There is a ton of blending, pitch and playrate tweaking, separate modifiers for current rpm and how much the accelerator is currently depressed. And yeah, like hundreds of recorded samples from the real car when possible, or a similar sounding car when not possible.

    We are probably on the verge of getting to a point where a rough simulation might soon be able to take over for this process. It won’t sound as good for a while still, but it will be cheaper and faster soon. And as time goes on, it’ll get close enough to sounding right while continuing to decrease in cost and time taken to a point where it’ll be the only way to do it eventually

    • Grass
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      5 months ago

      I’ve had the thought of using a video game engine synth for electric cars. all of my neighbors have evs and they are so freakishly quiet and I’ve almost walked into them a few times when leaving through the alley while being a phone zombie

      • Tarquinn2049@lemmy.world
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        5 months ago

        Most EVs actually play sounds already. Just older ones wouldn’t now. My brother set his to a spaceship sound. But you can pick normal sounds too, like various style ICE engine sounds.

        • Grass
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          5 months ago

          wait you mean it’s configurable? I think its the tesla I can hear leaving if my worse hearing side isn’t facing that way because it makes that weird scifi hovering sound. The other neighbor’s car just sounds like an air filter on medium so most of the time it just blends with the wind

          • Tarquinn2049@lemmy.world
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            5 months ago

            Yeah, on most models made in the last 5 years or so. Specifically for people with vision or partial hearing loss. But of course the ones that make fake engine sounds are also largely for the specific drivers those EVs are targetted at. They also tend to play them inside the cabin too. The fake engine sounds are pretty terrible though, like videogames from 20+ years ago.

          • Prison Mike@links.hackliberty.org
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            5 months ago

            I really can’t stand the Tesla sound, it’s the worst. I can’t quite put my finger on it but it’s both uncanny and grating. I’ll be in my apartment and suddenly there’s this high-pitched screaming of sorts; it doesn’t sound like the car is doing well.

      • Björn Tantau@swg-empire.de
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        5 months ago

        I remember there was the possibility in the talks to mandate some sound on EVs. I think Tesla wanted to use the sound of Blade Runner cars.

  • Cagi@lemmy.ca
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    5 months ago

    I remember exploring the Road Rash files as a kid and each bike sound was a single short click that just repeated rapidly. Times have changed.