Descent 2 has a hack, present as far back as I can trace, that
suppresses starting sounds during level load. The original reason was
not recorded, but this hack has the useful side effect that it avoids
using uninitialized data when set_sound_sources tries to use a Viewer
that has not been reset for the objects of the new level.
Descent 1 lacks this hack, so an invalid Viewer is used, which may
trigger a valptridx trap if the undefined data has an invalid segment
number, and could cause memory corruption in builds which do not
validate the segment index. The valptridx trap:
```
terminate called after throwing an instance of 'valptridx<dcx::segment>::index_range_exception'
what(): similar/main/digiobj.cpp:389: invalid index used in array subscript: base=(nil) size=9000 index=65021
```
The backtrace leading to the trap:
```
d1x::digi_link_sound_common (viewer=..., so=..., pos=..., forever=<optimized out>, max_volume=<optimized out>, max_distance=..., soundnum=42, segnum=...) at similar/main/digiobj.cpp:389
0x00005555555a4e2d in d1x::digi_link_sound_to_pos2 (vcobjptr=..., max_distance=..., max_volume=32768, forever=1, pos=..., sidenum=4, segnum=..., org_soundnum=121) at similar/main/digiobj.cpp:483
d1x::digi_link_sound_to_pos (soundnum=soundnum@entry=121, segnum=..., sidenum=sidenum@entry=4, pos=..., forever=forever@entry=1, max_volume=32768) at similar/main/digiobj.cpp:490
0x00005555555c140d in d1x::set_sound_sources (vcsegptridx=..., vcvertptr=...) at similar/main/gameseq.cpp:817
d1x::LoadLevel (level_num=<optimized out>, page_in_textures=1) at similar/main/gameseq.cpp:1022
0x00005555555c2654 in d1x::StartNewLevelSub (level_num=-1, page_in_textures=<optimized out>) at similar/main/gameseq.cpp:1865
```
Backport this hack into Descent 1. Ultimately, the hack should go away
and data should be loaded in an order that does not access undefined
memory.
Reported-by: Spacecpp <https://github.com/dxx-rebirth/dxx-rebirth/issues/463>
digi_play_sample_once is supposed to cancel prior instances of the
sound, but that functionality was lost in
21082c6db2. As a result, the sound can be
stacked up to the limit of the engine. Even when the functionality
existed, its implementation was wrong.
- Change these sounds to be attached to the player generating them.
- Pass the cancellation flag to other players when sending a sound.
- Send the full value of `volume`, rather than truncating it.
- Implement cancellation by killing and restarting the earlier version of a cancelled sound.
- Delete an ugly hack that prevented the patched logic from ever running.
- Fix an ancient quirk in digi_mixer that caused it to report all sounds as not playing, which then caused digi_sync_sounds to instantly cancel the new sound.
Reported-by: Mako88 <https://github.com/dxx-rebirth/dxx-rebirth/issues/88>
Reported-by: ryusei117 <https://github.com/dxx-rebirth/dxx-rebirth/issues/88#issuecomment-269597361>
Fixes: 21082c6db2 ("Added own channel management to SDL_mixer sound interface since the builtin channel management of this lib cannot handle our needs; Little code cleanup")
All supported compilers have an acceptable <type_traits>. Commit
4cb3d46148 ("Move <type_traits> test to Cxx11RequiredFeature") made
<type_traits> support mandatory in August and no one has objected.
Remove the indirection and use namespace std directly for type_traits
members.
Previously, valptridx used PREFIX for allow-invalid+mutable, c#PREFIX
for allow-invalid+const, v#PREFIX for require-valid+mutable, vc#PREFIX
for require-valid+const. Convert the types, factories, and all usage
sites to specify a qualifier for all four combinations:
im#PREFIX -> allow-invalid+mutable
ic#PREFIX -> allow-invalid+const
vm#PREFIX -> require-valid+mutable
vc#PREFIX -> require-valid+const
Changes to common/include/valptridx.h and common/include/fwd-valptridx.h
are manual. All other changes are generated by:
git grep -lz -e '\(obj\|seg\|clwall\|wall\|actdoor\|trg\)\(ptridx\|ptr\|idx\)\(_t\)\?\>' | xargs -0 sed -i -e 's/\<\(v\?\)\(\(obj\|seg\|clwall\|wall\|actdoor\|trg\)\(ptridx\|ptr\|idx\)\(_t\)\?\)\>/\1m\2/g'
for the 'm' prefix and:
git grep -lz -e '\(obj\|seg\|clwall\|wall\|actdoor\|trg\)\(ptridx\|ptr\|idx\)\(_t\)\?\>' | xargs -0 sed -i -e 's/\<\([cm]\(obj\|seg\|clwall\|wall\|actdoor\|trg\)\(ptridx\|ptr\|idx\)\(_t\)\?\)\>/i&/g'
for the 'i' prefix.
gcc-4.7 (and, if constructor inheritance is suppressed, later versions)
reject
return objnum == object_none ? vcobjptr(static_cast<objnum_t>(object_first)) : objnum;
where objnum is a cobjptridx:
similar/main/digiobj.cpp: In lambda function:
similar/main/digiobj.cpp:564:85: error: operands to ?: have different types 'valptridx<object>::vcptr' and 'valptridx<object>::cptridx'
similar/main/digiobj.cpp:564:85: error: inconsistent types '<type error>' and 'valptridx<object>::vcptr' deduced for lambda return type
Fix it by removing the ternary operator and adding an appropriate
conversion cast.
If a sound is used, it may dereference Viewer. If Viewer is null, this
will crash. In 630f11945e,
digi_sync_sounds changed to assume Viewer is valid. This crashes during
early startup when not using the SDL_mixer backend, even though no
sounds are in use.
Reported-by: derhass <https://github.com/dxx-rebirth/dxx-rebirth/issues/45>
Fixes: 630f11945e ("Cache Viewer in digiobj")