Commit d0d7545ec1 ("Unload robot movies on exit") intended to shorten
the lifetime of the loaded data, but failed to save the unique_ptr, so
the lifetime was shortened more than intended. Save the unique_ptr so
that the movies remain loaded.
Also, add a [[nodiscard]] annotation so that the compiler can warn if
this mistake is repeated.
Reported-by: Q3BFG10K <https://github.com/dxx-rebirth/dxx-rebirth/issues/599>
Fixes: d0d7545ec1 ("Unload robot movies on exit")
The previous commit removed an incorrect double scaling of the player's
weapon sounds, which will make all such sounds louder. Players with
their FX volume set to maximum will now have twice as loud a sound.
Halve the intensity in the source to return to the volume such players
would have had before. Players with an FX volume less than maximum will
still get a somewhat louder sound than before.
The SDL_mixer library has already been instructed, via Mix_Volume, to
scale the volume of sounds on all channels, by an amount based on
digi_volume. There is no need to manipulate the effective distance of a
particular sound to further scale it by digi_volume. Even if this
second scale was needed, it was done incorrectly, because it was only
applied when the sound was started, but not re-applied when the sound's
volume was updated due to positional changes. As a result, any sound
which was updated would switch to an unscaled version. Sounds which
were never updated, such as those attached to the viewer object, would
retain their original scaled volume.
Update the implementation of digi_mixer_set_channel_volume to call
Mix_SetDistance in the same way as digi_mixer_start_sound, for
readability and consistency.
Some callers need to update an existing sound_object. Other callers
need a temporary copy of the data for external use. Rearrange the code
so that the latter type of caller can obtain the data without a pointer
indirection.
gcc treats the intervening lines since the last `if` as sufficient to
recognize this as not misleading. clang does not. Change the indent to
calm clang.
