Fix for [#21983] Entering Particle Edit mode crash

3 files changed, 19 insertions, 6 deletions

diff --git a/source/blender/blenkernel/BKE_pointcache.h b/source/blender/blenkernel/BKE_pointcache.h
index 170965a223a..03a86b6566a 100644
--- a/source/blender/blenkernel/BKE_pointcache.h
+++ b/source/blender/blenkernel/BKE_pointcache.h
@@ -258,6 +258,7 @@ int		BKE_ptcache_data_size(int data_type);
 /* Memory cache read/write helpers. */
 void BKE_ptcache_mem_init_pointers(struct PTCacheMem *pm);
 void BKE_ptcache_mem_incr_pointers(struct PTCacheMem *pm);
+int BKE_ptcache_mem_seek_pointers(int point_index, struct PTCacheMem *pm);
 
 /* Copy a specific data type from cache data to point data. */
 void	BKE_ptcache_data_get(void **data, int type, int index, void *to);
diff --git a/source/blender/blenkernel/intern/pointcache.c b/source/blender/blenkernel/intern/pointcache.c
index 807e25955a7..6b8d5b3b70f 100644
--- a/source/blender/blenkernel/intern/pointcache.c
+++ b/source/blender/blenkernel/intern/pointcache.c
@@ -1328,7 +1328,7 @@ void BKE_ptcache_mem_incr_pointers(PTCacheMem *pm)
 			pm->cur[i] = (char*)pm->cur[i] + ptcache_data_size[i];
 	}
 }
-static int BKE_ptcache_mem_seek_pointers(int point_index, PTCacheMem *pm)
+int BKE_ptcache_mem_seek_pointers(int point_index, PTCacheMem *pm)
 {
 	int data_types = pm->data_types;
 	int i, index = pm->index_array ? pm->index_array[point_index] - 1 : point_index;
diff --git a/source/blender/editors/physics/particle_edit.c b/source/blender/editors/physics/particle_edit.c
index d20e0e87934..b45b06d2a39 100644
--- a/source/blender/editors/physics/particle_edit.c
+++ b/source/blender/editors/physics/particle_edit.c
@@ -3663,6 +3663,8 @@ static void make_PTCacheUndo(PTCacheEdit *edit, PTCacheUndo *undo)
 		for(; pm; pm=pm->next) {
 			for(i=0; i<BPHYS_TOT_DATA; i++)
 				pm->data[i] = MEM_dupallocN(pm->data[i]);
+
+			pm->index_array = MEM_dupallocN(pm->index_array);
 		}
 	}
 
@@ -3737,6 +3739,8 @@ static void get_PTCacheUndo(PTCacheEdit *edit, PTCacheUndo *undo)
 			for(i=0; i<BPHYS_TOT_DATA; i++)
 				pm->data[i] = MEM_dupallocN(pm->data[i]);
 
+			pm->index_array = MEM_dupallocN(pm->index_array);
+
 			BKE_ptcache_mem_init_pointers(pm);
 
 			LOOP_POINTS {
@@ -4001,12 +4005,20 @@ static void PE_create_particle_edit(Scene *scene, Object *ob, PointCache *cache,
 
 				LOOP_POINTS {
 					if(psys) {
-						pa = psys->particles + p;
-						if((pm->next && pm->next->frame < pa->time)
-							|| (pm->prev && pm->prev->frame >= pa->dietime)) {
-								BKE_ptcache_mem_incr_pointers(pm);
+						if(pm->index_array) {
+							if(pm->index_array[p])
+								BKE_ptcache_mem_seek_pointers(p, pm);
+							else
 								continue;
-							}
+						}
+						else {
+							pa = psys->particles + p;
+							if((pm->next && pm->next->frame < pa->time)
+								|| (pm->prev && pm->prev->frame >= pa->dietime)) {
+									BKE_ptcache_mem_incr_pointers(pm);
+									continue;
+								}
+						}
 					}
 
 					if(!point->totkey) {