Constraints: introduce wrapper functions to access target lists.

Instead of directly accessing constraint-specific callbacks
in code all over blender, introduce two wrappers to retrieve
and free the target list.

This incidentally revealed a place within the Collada exporter
in BCAnimationSampler.cpp that didn't clean up after retrieving
the targets, resulting in a small memory leak. Fixing this should
be the only functional change in this commit.

This was split off from D9732.

Differential Revision: https://developer.blender.org/D13844

1 files changed, 3 insertions, 8 deletions

diff --git a/source/blender/io/collada/SceneExporter.cpp b/source/blender/io/collada/SceneExporter.cpp
index ea95729666a..1b1da110573 100644
--- a/source/blender/io/collada/SceneExporter.cpp
+++ b/source/blender/io/collada/SceneExporter.cpp
@@ -191,24 +191,19 @@ void SceneExporter::writeNode(Object *ob)
           /* not ideal: add the target object name as another parameter.
            * No real mapping in the `.dae`.
            * Need support for multiple target objects also. */
-          const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
-          ListBase targets = {nullptr, nullptr};
-          if (cti && cti->get_constraint_targets) {
 
+          ListBase targets = {nullptr, nullptr};
+          if (BKE_constraint_targets_get(con, &targets)) {
             bConstraintTarget *ct;
             Object *obtar;
 
-            cti->get_constraint_targets(con, &targets);
-
             for (ct = (bConstraintTarget *)targets.first; ct; ct = ct->next) {
               obtar = ct->tar;
               std::string tar_id((obtar) ? id_name(obtar) : "");
               colladaNode.addExtraTechniqueChildParameter("blender", con_tag, "target_id", tar_id);
             }
 
-            if (cti->flush_constraint_targets) {
-              cti->flush_constraint_targets(con, &targets, true);
-            }
+            BKE_constraint_targets_flush(con, &targets, true);
           }
 
           con = con->next;