diff options
author | Bastien Montagne <montagne29@wanadoo.fr> | 2017-08-11 17:51:19 +0300 |
---|---|---|
committer | Bastien Montagne <montagne29@wanadoo.fr> | 2017-08-11 18:08:41 +0300 |
commit | 00cb3527902b11b5f136432e8670e299789b6716 (patch) | |
tree | 3a1aed650b83d088a10853fc0464daa5daca27e5 /source/blender | |
parent | c034193821ec7e67a0ae1050c8ccef7b5cd5473b (diff) |
Fix T52149: LoopTriArray computation was not correctly protected against concurrency.
Note: this commit seems to work as expected (also with transform
snapping etc.). However, it is rather unsafe - not enough for 2.79 at
least, unless we get much more testing on it. It also depends on three
previous ones.
Note that using a global lock here is far from ideal, we should rather
have a lock per DM, but that will do for now, whole DM thing is doomed
to oblivion anyway in 2.8.
Also, we may need a `DM_DIRTY_LOOPTRIS` dirty flag at some point. Looks
like we can survive without it for now though... Probably because cached
looptris are never copied accross DM's?
Diffstat (limited to 'source/blender')
-rw-r--r-- | source/blender/blenkernel/BKE_DerivedMesh.h | 2 | ||||
-rw-r--r-- | source/blender/blenkernel/intern/DerivedMesh.c | 12 | ||||
-rw-r--r-- | source/blender/blenkernel/intern/subsurf_ccg.c | 5 |
3 files changed, 14 insertions, 5 deletions
diff --git a/source/blender/blenkernel/BKE_DerivedMesh.h b/source/blender/blenkernel/BKE_DerivedMesh.h index 5a4fdcf2510..e2577689101 100644 --- a/source/blender/blenkernel/BKE_DerivedMesh.h +++ b/source/blender/blenkernel/BKE_DerivedMesh.h @@ -220,7 +220,7 @@ struct DerivedMesh { /** Recalculates mesh tessellation */ void (*recalcTessellation)(DerivedMesh *dm); - /** Loop tessellation cache */ + /** Loop tessellation cache (WARNING! Only call inside threading-protected code!) */ void (*recalcLoopTri)(DerivedMesh *dm); /** accessor functions */ const struct MLoopTri *(*getLoopTriArray)(DerivedMesh * dm); diff --git a/source/blender/blenkernel/intern/DerivedMesh.c b/source/blender/blenkernel/intern/DerivedMesh.c index 7a05ab4530c..e53f14291b7 100644 --- a/source/blender/blenkernel/intern/DerivedMesh.c +++ b/source/blender/blenkernel/intern/DerivedMesh.c @@ -93,6 +93,10 @@ static DerivedMesh *navmesh_dm_createNavMeshForVisualization(DerivedMesh *dm); # define ASSERT_IS_VALID_DM(dm) #endif + +static ThreadMutex loops_cache_lock = BLI_MUTEX_INITIALIZER; + + static void add_shapekey_layers(DerivedMesh *dm, Mesh *me, Object *ob); static void shapekey_layers_to_keyblocks(DerivedMesh *dm, Mesh *me, int actshape_uid); @@ -241,7 +245,13 @@ static const MLoopTri *dm_getLoopTriArray(DerivedMesh *dm) BLI_assert(dm->getNumLoopTri(dm) == dm->looptris.num); } else { - dm->recalcLoopTri(dm); + BLI_mutex_lock(&loops_cache_lock); + /* We need to ensure array is still NULL inside mutex-protected code, some other thread might have already + * recomputed those looptris. */ + if (dm->looptris.array == NULL) { + dm->recalcLoopTri(dm); + } + BLI_mutex_unlock(&loops_cache_lock); } return dm->looptris.array; } diff --git a/source/blender/blenkernel/intern/subsurf_ccg.c b/source/blender/blenkernel/intern/subsurf_ccg.c index 47dea5ea282..ff0682258c6 100644 --- a/source/blender/blenkernel/intern/subsurf_ccg.c +++ b/source/blender/blenkernel/intern/subsurf_ccg.c @@ -4474,10 +4474,10 @@ static void ccgDM_recalcTessellation(DerivedMesh *UNUSED(dm)) /* Nothing to do: CCG handles creating its own tessfaces */ } +/* WARNING! *MUST* be called in an 'loops_cache_rwlock' protected thread context! */ static void ccgDM_recalcLoopTri(DerivedMesh *dm) { - BLI_rw_mutex_lock(&loops_cache_rwlock, THREAD_LOCK_WRITE); - MLoopTri *mlooptri; + MLoopTri *mlooptri = dm->looptris.array; const int tottri = dm->numPolyData * 2; int i, poly_index; @@ -4502,7 +4502,6 @@ static void ccgDM_recalcLoopTri(DerivedMesh *dm) lt->tri[2] = (poly_index * 4) + 2; lt->poly = poly_index; } - BLI_rw_mutex_unlock(&loops_cache_rwlock); } static void ccgDM_calcNormals(DerivedMesh *dm) |