Revert r54058, caused crash when adding paritcles in particle edit mode

MEM_recallocN() doesn't allocate memory when used on a null pointer.

Just revert commit since there is no real benefit to using
MEM_recallocN() in this case.

1 files changed, 11 insertions, 4 deletions

diff --git a/source/blender/editors/physics/particle_edit.c b/source/blender/editors/physics/particle_edit.c
index 801b95bce25..deddc649956 100644
--- a/source/blender/editors/physics/particle_edit.c
+++ b/source/blender/editors/physics/particle_edit.c
@@ -3314,14 +3314,21 @@ static int brush_add(PEData *data, short number)
 		int newtotpart=totpart+n;
 		float hairmat[4][4], cur_co[3];
 		KDTree *tree=0;
-		ParticleData *pa;
-		PTCacheEditPoint *point;
+		ParticleData *pa, *new_pars = MEM_callocN(newtotpart*sizeof(ParticleData), "ParticleData new");
+		PTCacheEditPoint *point, *new_points = MEM_callocN(newtotpart*sizeof(PTCacheEditPoint), "PTCacheEditPoint array new");
 		PTCacheEditKey *key;
 		HairKey *hkey;
 
+		/* save existing elements */
+		memcpy(new_pars, psys->particles, totpart * sizeof(ParticleData));
+		memcpy(new_points, edit->points, totpart * sizeof(PTCacheEditPoint));
+
 		/* change old arrays to new ones */
-		psys->particles = MEM_recallocN(psys->particles, newtotpart * sizeof(ParticleData));
-		edit->points    = MEM_recallocN(edit->points,    newtotpart * sizeof(PTCacheEditPoint));
+		if (psys->particles) MEM_freeN(psys->particles);
+		psys->particles= new_pars;
+
+		if (edit->points) MEM_freeN(edit->points);
+		edit->points= new_points;
 
 		if (edit->mirror_cache) {
 			MEM_freeN(edit->mirror_cache);