1 files changed, 21 insertions, 17 deletions

diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index 2db4c466443..e3f7ae1b1c7 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -4054,32 +4054,36 @@ static void followtrack_evaluate(bConstraint *con, bConstraintOb *cob, ListBase
 				copy_v3_v3(cob->matrix[3], disp);
 			}
 
-			if (data->depth_ob && data->depth_ob->derivedFinal) {
+			if (data->depth_ob) {
 				Object *depth_ob = data->depth_ob;
-				BVHTreeFromMesh treeData = NULL_BVHTreeFromMesh;
-				BVHTreeRayHit hit;
-				float ray_start[3], ray_end[3], ray_nor[3], imat[4][4];
-				int result;
+				DerivedMesh *target = object_get_derived_final(depth_ob);
+				if (target) {
+					BVHTreeFromMesh treeData = NULL_BVHTreeFromMesh;
+					BVHTreeRayHit hit;
+					float ray_start[3], ray_end[3], ray_nor[3], imat[4][4];
+					int result;
 
-				invert_m4_m4(imat, depth_ob->obmat);
+					invert_m4_m4(imat, depth_ob->obmat);
 
-				mul_v3_m4v3(ray_start, imat, camob->obmat[3]);
-				mul_v3_m4v3(ray_end, imat, cob->matrix[3]);
+					mul_v3_m4v3(ray_start, imat, camob->obmat[3]);
+					mul_v3_m4v3(ray_end, imat, cob->matrix[3]);
 
-				sub_v3_v3v3(ray_nor, ray_end, ray_start);
+					sub_v3_v3v3(ray_nor, ray_end, ray_start);
 
-				bvhtree_from_mesh_faces(&treeData, depth_ob->derivedFinal, 0.0f, 4, 6);
+					bvhtree_from_mesh_faces(&treeData, target, 0.0f, 4, 6);
 
-				hit.dist = FLT_MAX;
-				hit.index = -1;
+					hit.dist = FLT_MAX;
+					hit.index = -1;
 
-				result = BLI_bvhtree_ray_cast(treeData.tree, ray_start, ray_nor, 0.0f, &hit, treeData.raycast_callback, &treeData);
+					result = BLI_bvhtree_ray_cast(treeData.tree, ray_start, ray_nor, 0.0f, &hit, treeData.raycast_callback, &treeData);
 
-				if (result != -1) {
-					mul_v3_m4v3(cob->matrix[3], depth_ob->obmat, hit.co);
-				}
+					if (result != -1) {
+						mul_v3_m4v3(cob->matrix[3], depth_ob->obmat, hit.co);
+					}
 
-				free_bvhtree_from_mesh(&treeData);
+					free_bvhtree_from_mesh(&treeData);
+					target->release(target);
+				}
 			}
 		}
 	}