Expand and stage boss encounter

audio/make_sfx.py

@@ -183,9 +183,32 @@ def explosion(seconds, sub_from, sub_to, roar_seed, debris_level, drive):
     return [_saturate(v, drive) * _attack(i, 0.001) for i, v in enumerate(mixed)]
 
 
+def boss_scream(seconds=1.65):
+    """A huge synthetic creature waking: a rough falling throat tone with
+    an unstable upper rasp. Long enough to carry the reveal shake, without
+    borrowing a human/animal recording whose licence would need tracking."""
+    n = int(RATE * seconds)
+    throat = [0.0] * n
+    phase = 0.0
+    for i in range(n):
+        t = i / n
+        hz = 118.0 * (52.0 / 118.0) ** (t ** 0.72)
+        hz *= 1.0 + 0.07 * math.sin(t * math.pi * 17.0)
+        phase += 2.0 * math.pi * hz / RATE
+        envelope = min(1.0, t / 0.06) * (1.0 - t) ** 0.75
+        throat[i] = (math.sin(phase) * 0.75 + math.sin(phase * 2.03) * 0.32
+                     + math.sin(phase * 3.97) * 0.16) * envelope
+    rasp_noise = _noise(n, 189, lambda t: 0.34 * (1.0 - t) + 0.025)
+    rasp = [value * min(1.0, i / (RATE * 0.025)) * _decay(i, n, 1.15) * 0.68
+            for i, value in enumerate(rasp_noise)]
+    mixed = _mix(throat, rasp)
+    return [_saturate(value, 3.2) for value in mixed]
+
+
 if __name__ == "__main__":
     _write("sfx_shot", shot())
     _write("sfx_dialog", dialog())
+    _write("sfx_boss_scream", boss_scream())
     # A vessel coming apart: bright, fast, with real low end under it.
     _write("sfx_ship_death", explosion(1.45, 260.0, 38.0, 5, 0.16, 2.6))
     # A structure: longer, deeper, and it keeps coming down afterwards.