Restore landing fade and missing event sounds

audio/make_sfx.py

@@ -125,6 +125,28 @@ def shot(seconds=0.22):
     return [_saturate(v, 2.0) * _attack(i, 0.0015) for i, v in enumerate(mixed)]
 
 
+def dialog(seconds=0.24):
+    """A short radio handshake when a transmission line appears.
+
+    Two rising digital tones establish the signal; a small static tail keeps
+    it in the same physical world as the scan-line presentation without
+    turning every revealed character into a click."""
+    n = int(RATE * seconds)
+    tone = [0.0] * n
+    for start, end, level, delay in ((520.0, 820.0, 0.55, 0.0),
+                                     (940.0, 1380.0, 0.32, 0.045)):
+        begin = int(RATE * delay)
+        part = _sweep(n - begin, start, end, 0.8)
+        for i, value in enumerate(part):
+            at = begin + i
+            tone[at] += value * level * _decay(i, len(part), 2.8)
+    static = [value * _decay(i, n, 2.1) * 0.16
+              for i, value in enumerate(_noise(n, 17, lambda t: 0.55 - 0.42 * t))]
+    mixed = _mix(tone, static)
+    return [_saturate(value, 1.8) * _attack(i, 0.002)
+            for i, value in enumerate(mixed)]
+
+
 def explosion(seconds, sub_from, sub_to, roar_seed, debris_level, drive):
     """A blast in three layers on three clocks: the crack is over in a
     fifth of a second, the roar runs most of the length, and the debris
@@ -163,6 +185,7 @@ def explosion(seconds, sub_from, sub_to, roar_seed, debris_level, drive):
 
 if __name__ == "__main__":
     _write("sfx_shot", shot())
+    _write("sfx_dialog", dialog())
     # 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.