No line for constraint without target

Code notes:

The constraint_has_target can be used to test if a constraint has a target at all.

2 files changed, 57 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_constraint.h b/source/blender/blenkernel/BKE_constraint.h
index 0a878d93ebe..6570f547e48 100644
--- a/source/blender/blenkernel/BKE_constraint.h
+++ b/source/blender/blenkernel/BKE_constraint.h
@@ -55,6 +55,7 @@ void do_constraint_channels (struct ListBase *conbase, struct ListBase *chanbase
 short get_constraint_target (struct bConstraint *con, short ownertype, void *ownerdata, float mat[][4], float size[3], float time);
 struct bConstraintChannel *find_constraint_channel (ListBase *list, const char *name);
 void free_constraint_channels (ListBase *chanbase);
+char constraint_has_target (struct bConstraint *con);
 
 /* Constraint target/owner types */
 #define TARGET_OBJECT			1	//	string is ""
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index 10e29759347..9e9a0c51405 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -70,6 +70,62 @@ static void constraint_target_to_mat4 (Object *ob, const char *substring, float
 
 /* Functions */
 
+char constraint_has_target (bConstraint *con) {
+	switch (con->type){
+	case CONSTRAINT_TYPE_TRACKTO:
+		{
+			bTrackToConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_KINEMATIC:
+		{
+			bKinematicConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_FOLLOWPATH:
+		{
+			bFollowPathConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_ROTLIKE:
+		{
+			bRotateLikeConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_LOCLIKE:
+		{
+			bLocateLikeConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_ACTION:
+		{
+			bActionConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	case CONSTRAINT_TYPE_LOCKTRACK:
+		{
+			bLockTrackConstraint *data = con->data;
+			if (data->tar)
+				return 1;
+		}
+		break;
+	}
+	// Unknown types or CONSTRAINT_TYPE_NULL or  no target
+	return 0;
+}
+
 void unique_constraint_name (bConstraint *con, ListBase *list){
 	char		tempname[64];
 	int			number;