Fix crash when having multiple text objects sharing the same curve datablock

Issue was caused by BKE_vfont_to_curve() modifying curve->nurbs list which
gave threading issues.

Now added BKE_vfont_to_curve_nubase() which operates on a given nurbs list
base which is local in do_makeDispListCurveTypes().

By the looks of it it wouldn't give speed regression because previously it
also was creating nurbs for every font object sharing the same curve data.

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_font.h b/source/blender/blenkernel/BKE_font.h
index 85aaafda39f..199b19402aa 100644
--- a/source/blender/blenkernel/BKE_font.h
+++ b/source/blender/blenkernel/BKE_font.h
@@ -83,6 +83,9 @@ void BKE_vfont_free(struct VFont *sc);
 struct VFont *BKE_vfont_builtin_get(void);
 struct VFont *BKE_vfont_load(struct Main *bmain, const char *name);
 
+bool BKE_vfont_to_curve_nubase(struct Main *bmain, struct Scene *scene, struct Object *ob,
+                               struct ListBase *nubase, int mode, struct CharTrans **r_chartransdata);
+
 bool BKE_vfont_to_curve(struct Main *bmain, struct Scene *scene, struct Object *ob, int mode,
                         struct CharTrans **r_chartransdata);