Actor's position can be determined in 3 ways:
1/ as a result of physics simulation
2/ after a script require a relative position change (SetPos, Move)
3/ absolutely set from games mechanics event (teleport) or script
(PositionCell)
In case 1/, RefData::mPosition is updated with the physics simulation result
In case 2/, when RefData::mPosition is updated, physics simulation is informed of the change and update accordingly
In case 3/, when RefData::mPosition is updated, the physics simulation state is reset
In all 3 cases, we don't need to check the RefData::mPosition to get a
correct behaviour.
TSAN reported the following data race:
Read of size 4 at 0x7b50005b75b0 by thread T12 (mutexes: write M656173, write M84859534346343880):
#0 ESM::Position::asVec3() const /build/openmw/openmw/master2/.build/freebsd/TSAN/../../.././components/esm/defs.hpp:55:27 (openmw+0xb809d5)
#1 MWPhysics::Actor::updateWorldPosition() /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/actor.cpp:131:59 (openmw+0xb809d5)
#2 MWPhysics::Actor::setPosition(osg::Vec3f const&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/actor.cpp:177:5 (openmw+0xb809d5)
#3 MWPhysics::PhysicsTaskScheduler::updateActorsPositions() /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/mtphysics.cpp:524:28 (openmw+0xb91ac0)
#4 MWPhysics::PhysicsTaskScheduler::afterPostStep() /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/mtphysics.cpp:614:13 (openmw+0xb915e7)
#5 MWPhysics::PhysicsTaskScheduler::worker()::$_5::operator()() const /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/mtphysics.cpp:498:45 (openmw+0xb915e7)
#6 void Misc::Barrier::wait<MWPhysics::PhysicsTaskScheduler::worker()::$_5>(MWPhysics::PhysicsTaskScheduler::worker()::$_5&&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../.././components/misc/barrier.hpp:30:21 (openmw+0xb915e7)
#7 MWPhysics::PhysicsTaskScheduler::worker() /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/mtphysics.cpp:498:31 (openmw+0xb915e7)
#8 MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0::operator()() const /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwphysics/mtphysics.cpp:162:45 (openmw+0xb92630)
#9 decltype(std::__1::forward<MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0>(fp)()) std::__1::__invoke<MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0>(MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0&&) /usr/include/c++/v1/type_traits:3899:1 (openmw+0xb92630)
#10 void std::__1::__thread_execute<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct> >, MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0>(std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct> >, MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0>&, std::__1::__tuple_indices<>) /usr/include/c++/v1/thread:280:5 (openmw+0xb92630)
#11 void* std::__1::__thread_proxy<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct> >, MWPhysics::PhysicsTaskScheduler::PhysicsTaskScheduler(float, btCollisionWorld*, MWRender::DebugDrawer*)::$_0> >(void*) /usr/include/c++/v1/thread:291:5 (openmw+0xb92630)
Previous write of size 8 at 0x7b50005b75b0 by main thread:
#0 memcpy /wrkdirs/usr/ports/devel/llvm-devel/work-default/llvm-project-3f6753efe1990a928ed120bd907940a9fb3e2fc3/compiler-rt/lib/tsan/../sanitizer_common/sanitizer_common_interceptors.inc:827:5 (openmw+0x55a057)
#1 MWWorld::RefData::setPosition(ESM::Position const&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwworld/refdata.cpp:216:19 (openmw+0xa3de1c)
#2 MWWorld::World::moveObject(MWWorld::Ptr const&, MWWorld::CellStore*, float, float, float, bool) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwworld/worldimp.cpp:1130:26 (openmw+0xa57300)
#3 MWWorld::World::moveObject(MWWorld::Ptr const&, float, float, float, bool, bool) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwworld/worldimp.cpp:1253:16 (openmw+0xa580c8)
#4 MWWorld::World::doPhysics(float, unsigned long long, unsigned int, osg::Stats&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwworld/worldimp.cpp:1530:17 (openmw+0xa5af8f)
#5 MWWorld::World::updatePhysics(float, bool, unsigned long long, unsigned int, osg::Stats&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/mwworld/worldimp.cpp:1862:13 (openmw+0xa61a7c)
#6 OMW::Engine::frame(float) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/engine.cpp:333:42 (openmw+0xcce9e7)
#7 OMW::Engine::go() /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/engine.cpp:935:14 (openmw+0xcd86ed)
#8 runApplication(int, char**) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/main.cpp:296:17 (openmw+0xcbffac)
#9 wrapApplication(int (*)(int, char**), int, char**, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../components/debug/debugging.cpp:205:15 (openmw+0x1335442)
#10 main /build/openmw/openmw/master2/.build/freebsd/TSAN/../../../apps/openmw/main.cpp:308:12 (openmw+0xcc008a)
:wqa
The plan is to add additional options to this new tab, and since it's of similar status as the Shaders settings, it makes sense to put them next to them on the Graphics page.
The idea is to avoid std::map lookup for each CellRef. Instead generate a
sequence of added and removed RefNums into a vector then order them by RefNum
using a stable sort that preserves relative order of elements with the same
RefNum. RefIDs are stored in a different vector to avoid std::string move ctor
calls when swapping elements while sorting. Reversed iteration over added and
removed RefNums for each unique RefNum is an equivalent to what map-based
algorithm produces. The main benefit from sorting a vector is a data locality
that means less cache misses for each access. Reduces ESMStore::countRecords
perf cycles by 25%.