Sound layering

[giftheck]

How exactly does sound layering work? I'm looking at the AT footstep sounds. I'm assuming it's something like having layered dynamic sounds (IE Sound layer A1, B2, C4 may play but then on the step step it might be A3, B6, C1). Have I got this right?

Also, what is the purpose of the "low" sounds? Are they sounds meant to be heard from a distance when you are not near enough to hear the main sounds?

[Marth8880]

It's just playing multiple sounds at the same time. You can even set a playback delay for each layer.

From soundreadme.txt:

Hidden/Spoiler:

[code]
ObjectID : SoundLayered
-----------------------

Property | Description
-------------------------------------------------------------------------------
Name | Name of the layered sound
Layer | Layer("layerName", "soundName", playbackDelay, playbackDelayDev,
| playbackTime, playbackTimeDev).
| The layer name is a label which allows the layer to be
| referenced by the application code. The sound name
| references the name of a previously defined Sound()
| which will be used as a layer of the layered sound.
| The playback delay, is the time to delay the sound
| (in seconds) from the time the sound is initially triggered.
| The playback delay deviation (playbackDelayDev) allows
| the playback delay to be randomly varied over a range.
| playbackTime is the time to play the layer, if this is not
| specified the layer will not stop. Finally, playbackTimeDev
| is the deviation of the playback time, if this is not specified
| a deviation of 0.0 is used.
| Any number of SoundLayers can be specified for a layered sound.

A layered sound (SoundLayered) allows multiple Sounds to be played back at the
same time or with some delay between each sound.

For example...

SoundLayered
{
Name("grenade_explode");
Layer("explosion", "grenade_explode", 0.0);
Layer("gasleak", "grenade_gas", 0.5, 0.1);
}

The sound "grenade_explode" will be played when the layered sound
"grenade_explode" is triggered (played). Then 0.4 to 0.6 seconds after the
layered sound "grenade_explode" was triggered, "grenade_gas" will play.[/code]

It's also especially useful for layering together weapon sounds with distant variants. Example from MEU:

Hidden/Spoiler:

[code]SoundProperties()
{
Name("sniper_rifle_fire_distant");
Group("weapons_sniper");
Inherit("me5_weapon_distant_template");
Gain(0.85);
RollInDistance(90.0);
MinDistance(100.0);
MuteDistance(550.0);
MaxDistance(550.0);
SampleList()
{
Sample("m_sniper_fire_distant-1", 0.5);
Sample("m_sniper_fire_distant-2", 0.5);
}
}

SoundProperties()
{
Name("sniper_rifle_fire_verydistant");
Group("weapons_sniper");
Inherit("me5_weapon_verydistant_template");
Gain(0.75);
RollInDistance(150.0);
MinDistance(175.0);
MuteDistance(900.0);
MaxDistance(900.0);
SampleList()
{
Sample("m_sniper_fire_verydistant-1", 0.5);
Sample("m_sniper_fire_verydistant-2", 0.5);
}
}

SoundProperties()
{
Name("m92_sniper_fire-1");
Group("weapons");
Inherit("me5_weapon_template");
Gain(1.0);
MinDistance(35.0);
MaxDistance(150.0);
MuteDistance(150.0);
Priority(6.0);
SampleList()
{
Sample("m92_fire1", 1.0);
Sample("m92_fire2", 1.0);
}
}

SoundProperties()
{
Name("m92_sniper_fire-2");
Group("weapons");
Inherit("me5_weapon_distant_template");
SampleList()
{
Sample("m92_fire-2", 1.0);
}
}

SoundProperties()
{
Name("m92_sniper_fire-3");
Group("weapons");
Inherit("me5_weapon_verydistant_template");
SampleList()
{
Sample("m92_fire-4", 1.0);
}
}

SoundLayered()
{
Name("m92_sniper_fire");
Layer("m92_fire-1", "m92_sniper_fire-1", 0.0);
Layer("m92_fire-2", "m92_sniper_fire-2", 0.0);
Layer("m92_fire-3", "m92_sniper_fire-3", 0.0);
Layer("m92_fire-4", "sniper_rifle_fire_distant", 0.0);
Layer("m92_fire-5", "sniper_rifle_fire_verydistant", 0.0);
}[/code]

You're essentially correct re: "low" sounds.