Fix #29005: Bezier/Surface Datablock switching bug?

This commit updates curve datablock to respect curve dimension flag
when setting datablock for curve.

Not ideal but this makes behavior quite expected, avoids big changes in
curves core stuff which depends on object type and prevents restrictions
on changing data datablock which works in general cases.

1 files changed, 27 insertions, 2 deletions

diff --git a/source/blender/blenkernel/intern/curve.c b/source/blender/blenkernel/intern/curve.c
index 5d2180fe702..adc08f5cd9f 100644
--- a/source/blender/blenkernel/intern/curve.c
+++ b/source/blender/blenkernel/intern/curve.c
@@ -315,9 +315,34 @@ short curve_type(Curve *cu)
 	return OB_CURVE;
 }
 
+void update_curve_dimension(Curve *cu)
+{
+	ListBase *nurbs= BKE_curve_nurbs(cu);
+	Nurb *nu= nurbs->first;
+
+	if(cu->flag&CU_3D) {
+		for( ; nu; nu= nu->next) {
+			nu->flag &= ~CU_2D;
+		}
+	}
+	else {
+		for( ; nu; nu= nu->next) {
+			nu->flag |= CU_2D;
+			test2DNurb(nu);
+
+			/* since the handles are moved they need to be auto-located again */
+			if(nu->type == CU_BEZIER)
+				calchandlesNurb(nu);
+		}
+	}
+}
+
 void test_curve_type(Object *ob)
-{	
-	ob->type = curve_type(ob->data);
+{
+	ob->type= curve_type(ob->data);
+
+	if(ob->type==OB_CURVE)
+		update_curve_dimension((Curve *)ob->data);
 }
 
 void tex_space_curve(Curve *cu)