New Acoustics system (globals/acoustics.gd):
- Occlusion: rays from listener to source collect up to 3 occluding bodies;
each surface's material adds transmission loss and lowers the lowpass
cutoff. A gunshot through wood stays warm (-8dB, 1.4kHz), brick muffles
hard (-15dB, 600Hz), concrete harder (-18dB, 450Hz), metal keeps more
highs (-11dB, 1kHz), glass barely muffles (-5dB, 2.6kHz). Applied via
each AudioStreamPlayer3D's attenuation filter.
- Early reflections: loud sounds (gunfire, explosions) probe 8 directions
for nearby walls; each close surface plays a quiet, delayed (path/343ms),
material-filtered copy from the mirror point — shots audibly slap back
off structures so players can triangulate. Sub-30ms echoes are skipped
(they perceptually merge with the direct sound).
- Surface classification: builder-set acoustic_material meta -> node-name
keywords -> metallic-material inference -> concrete default; cached.
Integration:
- AudioManager.play_3d applies occlusion at fire time and re-filters all
playing positional sounds every 0.12s (walking behind a wall mid-sound
audibly muffles it); flight loops opt in via "acoustic_occluded" group
- Remote players' gunshots were entirely SILENT — rpc_play_fire_effects now
plays the right weapon's shot at the shooter's position, occluded and
reflected like everything else
- Remote players' footsteps were also silent — now positional + occluded,
cadence scaled to their speed
- Test level tagged: brick arena walls, wooden platforms/obstacles, metal
wall-run corridor/rails/dash platforms; dust2 sandstone reads as brick
Tests: debug/acoustics_test.gd (12 checks: per-material loss ordering,
multi-wall stacking, reflection delay/filter, name classification) — all
pass; movement 11/11; smoke 0 failures.
Co-Authored-By: Claude Fable 5 <[email protected]>
