Fix #35504: Blender crashes on separating curves with different Evaluation Time / keyframes

Used slightly different approach from what was discussed with Campbell,
and the reason of this is slightly better support of curve point animation
re-mapping.

There're actually some limitations which better be discussed bewfore 'b':
- If there're no point animation, spline separation goes just fine.
- If there're animated points in the curve, blender will preserve
  animation for currently editing curve. But, since new curve created
  by Separate operator shares the same AnimData, it'll be animatied
  in a weird way.

So not sure whether it's better to preserve animation for current spline
but require switching animationdata for new spline or resetting animation
for current curve's animation data.

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/editors/curve/editcurve.c b/source/blender/editors/curve/editcurve.c
index 60e107b9c15..0383c0d1d1a 100644
--- a/source/blender/editors/curve/editcurve.c
+++ b/source/blender/editors/curve/editcurve.c
@@ -1177,6 +1177,10 @@ static void curve_rename_fcurves(Curve *cu, ListBase *orig_curves)
 int ED_curve_updateAnimPaths(Curve *cu)
 {
 	AnimData *adt = BKE_animdata_from_id(&cu->id);
+	EditNurb *editnurb = cu->editnurb;
+
+	if (!editnurb->keyindex)
+		return 0;
 
 	if (!curve_is_animated(cu)) return 0;
 
@@ -1416,12 +1420,14 @@ static int separate_exec(bContext *C, wmOperator *op)
 	newedit = newcu->editnurb;
 	BKE_nurbList_free(&newedit->nurbs);
 	BKE_curve_editNurb_keyIndex_free(newedit);
+	newedit->keyindex = NULL;
 
 	/* 3. move over parts from old object */
 	for (nu = oldedit->nurbs.first; nu; nu = nu1) {
 		nu1 = nu->next;
 
 		if (isNurbsel(nu)) {
+			keyIndex_delNurb(oldedit, nu);
 			BLI_remlink(&oldedit->nurbs, nu);
 			BLI_addtail(&newedit->nurbs, nu);
 		}