Seamless blending between snapshots using trigger volumes

Hello - I have a room setup with a grid of trigger volumes without gaps between them. Each trigger volume is assigned to a unique snapshot of convolution reverb made with impulse responses. When the player moves into each volume, I’d like to seamlessly blend into the appropriate snapshots without any hiccups or period of transition. For example, if you are in volume ‘A’, snapshot ‘A’ would be at 100% - as you start moving towards volume ‘B’, snapshot ‘A’'s influence should start transitioning down at the exact same rate as snapshot ‘B’'s influence is transitioning up so that as you arrive in volume ‘B’, snapshot ‘B’ is now at 100%. I hope I didn’t make that more confusing than it needs to be.

I’ve tried setting up the snapshots as overrides and tried abrupt transitions (play/stop in Unreal as you enter/exit trigger volumes) but I get a loud popping noise between them. I’ve tried adding AHDSR to the reverb pre-faders and it’s smoother, but I get a noticeable point where neither reverb is affecting the sound and it’s jarring.

Could anyone please recommend a good setup to get this working well? Thank you!

Could someone at FMOD offer a workflow for this please? I’m having difficulty getting this working and would love to know if this is possible. Thanks!

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I have the same question plus another issue.
My situation is that I have an intricate pattern of different reverb-rooms/reverb-areas.

Currently, I have a workaround in the World-Blueprint with additional trigger boxes, which block the stop/play in the critical areas (when the area is asymmetrical and should stay in the same reverb) and make sure, that the player can’t leave the reverb zone in little spots and corners.
(It’s a historic town with lots of small rooms and backyards)

Rather than using volumes, have you considered using parameters to automate snapshot intensity? Parameters grant you finer control than the binary on/off switch of entering or leaving a trigger volume.

For this to work, you will have to set the value of the parameter based on the player’s position in the game world - perhaps by creating a series of trigger volumes that set the value of both snapshots’ controlling parameter(s). Assigning a seek speed to those parameters will prevent them from changing too abruptly.


Thanks for the reply. If I am using a series of trigger volumes, wouldn’t that constrict me to specific values of snapshots instead of a smooth transition? Would it make more sense to transition based on the user’s position?


Not if you modulate or automate the snapshot’s intensity, as I suggested. Snapshot intensity represents the “opacity” of the snapshot, so to speak; if you automate or modulate intensity such that it ramps from 0% to 100% gradually, the property values scoped into the snapshot will likewise ramp gradually from their non-snapshot values to the values they have within the snapshot.

These ideas aren’t mutually exclusive. You can both trigger snapshots according to the player’s position and set the parameter that automates snapshot intensity according to player position, if you want.

Understood, thanks, joseph. I’ve had to move to Unity now so I’m in a little over my head with C# instead of Blueprints - what you’re saying makes sense though.