Refactor BKE_bpath module.

The main goal of this refactor is to make BPath module use `IDTypeInfo`,
and move each ID-specific part of the `foreach_path` looper into their
own IDTypeInfo struct, using a new `foreach_path` callback.

Additionally, following improvements/cleanups are included:
* Attempt to get better, more consistent namings.
** In particular, move from `path_visitor` to more standard `foreach_path`.
* Update and extend documentation.
** API doc was moved to header, according to recent discussions on this
   topic.
* Remove `BKE_bpath_relocate_visitor` from API, this is specific
  callback that belongs in `lib_id.c` user code.

NOTE: This commit is expected to be 100% non-behavioral-change. This
implies that several potential further changes were only noted as
comments (like using a more generic solution for
`lib_id_library_local_paths`, addressing inconsistencies like path of
packed libraries always being skipped, regardless of the
`BKE_BPATH_FOREACH_PATH_SKIP_PACKED` `eBPathForeachFlag` flag value,
etc.).

NOTE: basic unittests were added to master already in
rBdcc500e5a265093bc9cc.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D13381

1 files changed, 62 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/object.cc b/source/blender/blenkernel/intern/object.cc
index e3b9e4109ed..efb8cdd9c9d 100644
--- a/source/blender/blenkernel/intern/object.cc
+++ b/source/blender/blenkernel/intern/object.cc
@@ -83,6 +83,7 @@
 #include "BKE_animsys.h"
 #include "BKE_armature.h"
 #include "BKE_asset.h"
+#include "BKE_bpath.h"
 #include "BKE_camera.h"
 #include "BKE_collection.h"
 #include "BKE_constraint.h"
@@ -548,6 +549,66 @@ static void object_foreach_id(ID *id, LibraryForeachIDData *data)
   }
 }
 
+static void object_foreach_path_pointcache(ListBase *ptcache_list, BPathForeachPathData *bpath_data)
+{
+  for (PointCache *cache = (PointCache *)ptcache_list->first; cache != nullptr;
+       cache = cache->next) {
+    if (cache->flag & PTCACHE_DISK_CACHE) {
+      BKE_bpath_foreach_path_fixed_process(bpath_data, cache->path);
+    }
+  }
+}
+
+static void object_foreach_path(ID *id, BPathForeachPathData *bpath_data)
+{
+  Object *ob = reinterpret_cast<Object *>(id);
+
+  LISTBASE_FOREACH (ModifierData *, md, &ob->modifiers) {
+    /* TODO: Move that to #ModifierTypeInfo. */
+    switch (md->type) {
+      case eModifierType_Fluidsim: {
+        FluidsimModifierData *fluidmd = reinterpret_cast<FluidsimModifierData *>(md);
+        if (fluidmd->fss) {
+          BKE_bpath_foreach_path_fixed_process(bpath_data, fluidmd->fss->surfdataPath);
+        }
+        break;
+      }
+      case eModifierType_Fluid: {
+        FluidModifierData *fmd = reinterpret_cast<FluidModifierData *>(md);
+        if (fmd->type & MOD_FLUID_TYPE_DOMAIN && fmd->domain) {
+          BKE_bpath_foreach_path_fixed_process(bpath_data, fmd->domain->cache_directory);
+        }
+        break;
+      }
+      case eModifierType_Cloth: {
+        ClothModifierData *clmd = reinterpret_cast<ClothModifierData *>(md);
+        object_foreach_path_pointcache(&clmd->ptcaches, bpath_data);
+        break;
+      }
+      case eModifierType_Ocean: {
+        OceanModifierData *omd = reinterpret_cast<OceanModifierData *>(md);
+        BKE_bpath_foreach_path_fixed_process(bpath_data, omd->cachepath);
+        break;
+      }
+      case eModifierType_MeshCache: {
+        MeshCacheModifierData *mcmd = reinterpret_cast<MeshCacheModifierData *>(md);
+        BKE_bpath_foreach_path_fixed_process(bpath_data, mcmd->filepath);
+        break;
+      }
+      default:
+        break;
+    }
+  }
+
+  if (ob->soft != nullptr) {
+    object_foreach_path_pointcache(&ob->soft->shared->ptcaches, bpath_data);
+  }
+
+  LISTBASE_FOREACH (ParticleSystem *, psys, &ob->particlesystem) {
+    object_foreach_path_pointcache(&psys->ptcaches, bpath_data);
+  }
+}
+
 static void write_fmaps(BlendWriter *writer, ListBase *fbase)
 {
   LISTBASE_FOREACH (bFaceMap *, fmap, fbase) {
@@ -1266,6 +1327,7 @@ IDTypeInfo IDType_ID_OB = {
     /* make_local */ object_make_local,
     /* foreach_id */ object_foreach_id,
     /* foreach_cache */ nullptr,
+    /* foreach_path */ object_foreach_path,
     /* owner_get */ nullptr,
 
     /* blend_write */ object_blend_write,