Monster spawner only activating from a certain distance/height?

[KeaganDunn]

I currently have an MBF21 map in the works (essentially Boom but with extra features). At one point, I have a setup where the player hits a switch on the top right of the playable area, and all hell breaks loose -- to add to the effect, I have a monster spawner at the edge of the map that is revealed. It simply plays a distant alarm sound but doesn't spawn any cubes.

 

In the image below, the monster spawner is ~800 map units off the ground (or 800 units above where the player will be). Testing this in DSDA-Doom v0.19.3 and GZDoom v4.6, I noticed that the monster spawner does not "activate" unless I get close to it: up against the left wall of the playable area.

 

I did some research but came up with nothing. What I can draw from this is that the monster spawner thing does not "see" the player until they are less than ~2048 map units apart. Height does not seem to be a factor.

I might have an idea on where else to put the monster spawner thing since it doesn't have a visible sprite, but I haven't seen anything like this and wondering if it's a regular part of Doom's code.

Edited June 28, 2021 by Dunn (& Dunn)

[Aurelius]

If the only point of the spawner is to play a sound (and you're using MBF21), you could instead make any random thing that has A_PlaySound in it's Death state with the volume argument set to 1 (full volume), then simply have the activator kill it. Alternatively you can use two dummy things, one that calls A_NoiseAlert every tic and another thing that has A_PlaySound in it's see state, and simply have a floor lower in between them to expose the sound thing to the alerter.

 

Also, afaik GZDoom 4.6 does not support the new MBF21 features. A_PlaySound is an MBF feature so you should be fine with that approach.