Reported from the game: sounds sometimes start a bit late. The samples were
the suspect, so they were measured first - and they are clean. True digital
silence at the head of each file:
seven of nine start on sample 1
sfx_gas_blast 0.2ms
sfx_black_hole 1.5ms, then a deliberate swell
The black hole's slow attack is the sound it was written to be - make_sfx.py
says it "swells across most of its length instead of decaying from the first
sample" - so there is nothing to trim without breaking it.
The delay was in the playback path, and "sometimes" was the clue:
play() called load() every time. A cache hit after the first, but the
FIRST play of each sound was a synchronous read and decode on the frame
the sound was asked for. Ten sounds, ten occasional late starts.
_pool() built its twelve AudioStreamPlayer nodes lazily, on the first
play() call - one bigger stall, every session.
The catalog is preloaded now, so play() never touches the disk, and
Sfx.warm() builds the voices next to Music.ensure() at startup.
Case F pins the thing that was originally suspected, since make_sfx.py
regenerates these and a lazy envelope would hide the delay somewhere nobody
would look. It reads the source .wav's RIFF chunks rather than the imported
stream: these import as QOA (compress/mode=2), so AudioStreamWAV.data is not
PCM. The first version of that check was vacuous for exactly that reason and
passed at a 0.5ms threshold; it now reports "9 samples checked, worst attack
sfx_black_hole.wav at 1.5ms" and fails when tightened.
Not touched: project.godot has no [audio] section, so output_latency is at
its default. On Android that buffer is usually the dominant latency, but
lowering it risks crackle on real hardware - worth doing with someone
listening, not blind.
172/172.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019AJMdB7iuHuLFZM1aBu3GD
#204 the Beam Collimator widens the beam instead of adding range to one that
already crosses the screen; beam width becomes a per-shot vessel stat.
#205 the Energy Propulser gains three upgrades - dash recharge, dash reach,
and boosted-cruise drain - which turns three constants into vessel stats.
#206 three further doctrines carry the fleet from ten to twenty.
#207 the prologue's World Ship gets a marker, through the scanner's own
guidance arrow rather than a second one.
#208#210#213#214 four new synthesised sounds: the breach opening, cargo
reaching the hold, a rock breaking, and a gas bomb blooming.
#215 building health bars are larger, plated and framed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019AJMdB7iuHuLFZM1aBu3GD
Three events get a sound: a shot leaving a gun, a vessel dying, a structure
coming down.
The sounds are SYNTHESISED rather than downloaded - audio/make_sfx.py
generates all three from scratch, and is committed alongside them. The
ticket asked for free sources and the good ones are in its comments
(Kenney's CC0 packs, OpenGameArt's CC0 sets, Freesound filtered to CC0),
but a generated sound has no licence to track, no attribution to keep, and
no binary in the repository whose provenance nobody can check a year from
now. It also makes the sounds DATA: too sharp a shot is a number in that
file and a re-run, not a hunt through a library. Dropping in a pack file
later means replacing a .wav and nothing else.
A voice POOL, not a player, because these overlap constantly - a fleet
firing is several shots inside one shot's length. Twelve voices, and when
they are all busy the one furthest through its own sound is recycled, which
is the one with the least left to lose.
Parented to the tree root, for the reason that matters: every one of these
sounds is started by something that is being freed on the same frame. A
dying ship cannot own the sound of its own death.
Levels are per sound rather than shared - a shot fires constantly and a
death happens once, so equal volumes are not proportionate ones - and shots
get a little pitch spread so a stream of them does not flatten into one
machine-gun note. The deaths get none: a wobbling explosion sounds broken
rather than varied.
The test goes at the failures a play-through would hide for weeks: firing
three times the pool size must leave exactly the pool's worth sounding and
no leaked voices, and the ship-death case is checked from a node that really
has been freed on that frame.
