3D Reverb in FMOD Studio - Confusion

Hey Everyone!
I just found the FMOD Engine Documentation about 3D Reverbs - an awesome feature, which to me sounds way more convenient than snapshots, as those reverbs then actually exist in the world and aren’t a mix-overlay (like snapshots just have to behave in their own logic).
So I was wondering if there is any way to set up something similar in FMOD Studio directly to make use of the GUI interface for further mixing decision etc. and not only create a 3D Reverb in Code.

Looking forward to your answers and all the best!
Joshnt

It is, indeed, possible to design the kind of complex 3D reverbs you describe in FMOD Studio!

In fact, the Reverb DSP mentioned in the FMOD Engine documentation is the very same DSP that powers FMOD Studio’s reverb effect. Thus, you can use a reverb effect on a bus in FMOD Studio to produce the exact kinds of reverbs that you’re hoping for.

You’ll also need is a method of controlling the properties of that reverb effect. I assume you want to create the same kind of reverb volumes described in the 3D Reverbs whitepaper that you linked: Points in space, each with its own min and max distance that defines a spherical area around that point where the reverb is applied, which the FMOD Engine can interpolate between as the listener moves between them. Fortunately, it is trivially easy to build this kind of behavior with snapshots.

Snapshots can be assigned positions in 3D space and given 3D behavior in the same manner as events, which means it’s easy to make a snapshot that affects a spherical area and ramps up or down as the listener approaches or retreats from its center: All you have to do is automate the intensity property of the snapshot on a “distance” or “distance (normalized)” parameter such that the snapshot’s intensity is 0% at maximum distance and 100% at whatever distance you want to be the minimum distance.

To allow the FMOD engine to interpolate between different snapshots, you’ll have to ensure they’re the same priority. To do this, assign all your reverb snapshots to the same snapshot group.

Thus, if you create snapshots that represent your reverb zones, you can create instances of those snapshots and position them in the exact same positions that you would reverb zones created using the FMOD Engine’s 3D reverbs, and you’ll get the same behavior.

Oh, and because snapshots can be instanced, you’ll be able to reuse the same reverb snapshot for multiple reverb zones if those zones happen to have the same properties.

Awesome! Thank you a lot for your detailed answer, Joseph!

I was as well wondering: do the 3DReverbs created by code work on a per Event basis or (as the Reverb returns + snapshots in FMOD Studio) only for the listener? I’m thinking of a (made up) scenario, where you as a player might be standing in a small corridor leading to a large cave/ hall/ … and are hearing some enemy screaming from that large space. As the listener/ player triggers the snapshots/ determines the distance to them, that enemy scream would have the corridor reverb.
On the other hand, calculating the distance between each event and any snapshot (possibly even calculating which 2 snapshots are the closest) every update/ event tick to set e.g. the send amout to a specific reverb return on a per event basis sounds way to heavy on CPU. Is there a common “best practice” for that problem?
I think the main problem for me to wrap my head around, is that “reverb zones” aren’t actual reverb zones which any entity could enter and have their sounds placed in that reverb but are in fact listener dependend.

Thank you in advance for your answer!
All the best,
Joshn’t