enum SoundFlags

Option flags for playing a sound, see sound_play_t.

Enum Values


HeadLocked	Skip spatialization entirely: no distance attenuation, panning, or filtering. The sound follows the head, good for music, UI, or pre-rendered binaural content.
Loop	The sound restarts from the beginning when it reaches the end of its data, and plays until stopped. Live streams ignore this, they already wait for data forever.
None	No special behavior, the default.
PropagationDelay	Delay the sound’s onset by its distance from the listener divided by the speed of sound (343m/s), computed once when playback starts. Great for thunder, explosions, and other far away events.

Examples

Thunder along a lightning bolt

Sounds declare real-world loudness in decibels, and SoundFlags.PropagationDelay delays each voice’s onset by its distance at the speed of sound - so a thunder boom and its rumble arrive along the bolt just like the real thing. Energy sets the pitch here: bigger strikes boom deeper.

// A jagged bolt across the sky: the boom fires from its nearest
// point, then rumble instances arrive progressively later from
// farther along it - each duller (distance is a low-pass filter)
// and wider than the last.
float dist  = 80 + thunderDist * 1120;
float dir   = (float)(rand.NextDouble() * Math.PI * 2);
Vec3  near  = new Vec3(MathF.Cos(dir), 0, MathF.Sin(dir)) * dist + Vec3.Up * 90;
Vec3  far   = near + new Vec3(MathF.Sin(dir), 0.5f, -MathF.Cos(dir)) * (100 + (float)rand.NextDouble() * 300);
float pitch = 1.35f - thunderEnergy * 0.7f;

boomInst = boomSound.Play(near, new SoundPlay {
	flags = SoundFlags.PropagationDelay,
	pitch = pitch,
});

for (int i = 0; i < rumbleInsts.Length; i++)
{
	float t  = (i + 1) / (float)rumbleInsts.Length;
	Vec3  at = Vec3.Lerp(near, far, t);
	rumbleInsts[i] = rumbleSound.Play(at, new SoundPlay {
		flags  = SoundFlags.PropagationDelay,
		delay  = t * 0.5f,
		pitch  = pitch * (1.0f - t * 0.25f),
		volume = 1.0f - t * 0.3f,
		spread = 0.2f,
		cutoff = 900 - t * 550, // Air absorption along the bolt
	});
}

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