[getzabelz]

What

A Volume row on the Insert menu's Gameplay tab (above Audio output): a slider from Muted to 100% in steps of 5, 100% by default (the game's own level). It applies at once and is kept in hookshot_options.ini as volume=. Help line: "Master volume level."

How

• host/nn_audio.c: au_volume_apply scales the final mix in render_frame, after the limiter and before the samples become int16, with rx_option(HOS_OPT_VOLUME, 100) read once per 5 ms frame.
  • The gain is the square of the share (50% = -12 dB, 25% = -24 dB), so each step of the slider sounds about as large as the last.
  • It ramps from the last frame's gain to the new one over the frame, like the game's own volume changes, so dragging the slider does not click.
  • At 100% the samples are left untouched (early return).
• gpu/vk/vk_api.h: HOS_OPT_VOLUME (44), after HOS_OPT_DISCORD.
• gpu/vk/vk_replay.cpp: the option table answers it (clamped 0..100). An id the table does not answer reads as 0, which would silence the game, so the test checks for this line.
• gpu/vk/vk_menu.{h,cpp}: opts.volume, the row (preset_exempt, not a restart row), tx_volume, and the slider / stop-at-ends lists.
• readme.md: the options table and a line in the option notes.

Tests

• New tests/test_audio_volume.py (registered in run_all.py with --cc gcc): checks the row, the default, the slider flags, the enum and the renderer's answer, and that the call sits after the limiter. It also compiles the real au_volume_gain / au_volume_apply and checks 100% = unchanged, 0% = silence, 50% = 0.25, monotonic steps, and the ramp up and down without overshoot.
• Full run_all.py on Windows: everything passes except nup_paths, builder_dlss_update, fpx_sticky and precompile_compute_guard, which fail the same way on a clean main here (local environment).
• Built with the v2.0.13 builder and played in game: the slider changes the volume at once, Muted is silent, 100% sounds as before, and the value persists across restarts.

[getzabelz]

Closing this: #1270 (merged today) already adds a Volume slider in the new Audio tab, with the same curve (the square of the share) and ramp, plus Mute in background. It also saves as volume=, so players keep their setting. Thanks for the review!