Fix T71908: Animated properties are lost after frame-post handler

The issue was caused by special handling of animation update after
manual edits in frame_post handler: to avid loss of manual edits
done on top of animated property. This was done as a separate pass
for non-animation update after frame_post did modifications.

This caused some other side-effect: non-modified animated property
was re-setting to the value which is used in the viewport.

Idea of this solution is simple: preserve values which came from
animation update through copy-on-write process. The actual process
of this is a bit involved: need to decode RNA path and do it twice
since f-curve might point to a sub-data which pointer will change.
Since this is only done for non-active depsgraph (aka depsgraph
used for render pipeline) this is probably fine since all this
extra overhead is just a fraction of overall render process.

Differential Revision: https://developer.blender.org/D6330

5 files changed, 213 insertions, 1 deletions

diff --git a/source/blender/depsgraph/CMakeLists.txt b/source/blender/depsgraph/CMakeLists.txt
index 4abeec19645..7f3c7d5043f 100644
--- a/source/blender/depsgraph/CMakeLists.txt
+++ b/source/blender/depsgraph/CMakeLists.txt
@@ -59,6 +59,7 @@ set(SRC
   intern/eval/deg_eval_copy_on_write.cc
   intern/eval/deg_eval_flush.cc
   intern/eval/deg_eval_runtime_backup.cc
+  intern/eval/deg_eval_runtime_backup_animation.cc
   intern/eval/deg_eval_runtime_backup_modifier.cc
   intern/eval/deg_eval_runtime_backup_movieclip.cc
   intern/eval/deg_eval_runtime_backup_object.cc
@@ -108,6 +109,7 @@ set(SRC
   intern/eval/deg_eval_copy_on_write.h
   intern/eval/deg_eval_flush.h
   intern/eval/deg_eval_runtime_backup.h
+  intern/eval/deg_eval_runtime_backup_animation.h
   intern/eval/deg_eval_runtime_backup_modifier.h
   intern/eval/deg_eval_runtime_backup_movieclip.h
   intern/eval/deg_eval_runtime_backup_object.h
diff --git a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.cc b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.cc
index 88390ab412f..4da5ca77fb8 100644
--- a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.cc
+++ b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.cc
@@ -32,7 +32,8 @@
 namespace DEG {
 
 RuntimeBackup::RuntimeBackup(const Depsgraph *depsgraph)
-    : scene_backup(depsgraph),
+    : animation_backup(depsgraph),
+      scene_backup(depsgraph),
       sound_backup(depsgraph),
       object_backup(depsgraph),
       drawdata_ptr(NULL),
@@ -47,6 +48,8 @@ void RuntimeBackup::init_from_id(ID *id)
     return;
   }
 
+  animation_backup.init_from_id(id);
+
   const ID_Type id_type = GS(id->name);
   switch (id_type) {
     case ID_OB:
@@ -76,6 +79,8 @@ void RuntimeBackup::init_from_id(ID *id)
 
 void RuntimeBackup::restore_to_id(ID *id)
 {
+  animation_backup.restore_to_id(id);
+
   const ID_Type id_type = GS(id->name);
   switch (id_type) {
     case ID_OB:
diff --git a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.h b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.h
index 31ae3164e37..892cc88002f 100644
--- a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.h
+++ b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup.h
@@ -25,6 +25,7 @@
 
 #include "DNA_ID.h"
 
+#include "intern/eval/deg_eval_runtime_backup_animation.h"
 #include "intern/eval/deg_eval_runtime_backup_movieclip.h"
 #include "intern/eval/deg_eval_runtime_backup_object.h"
 #include "intern/eval/deg_eval_runtime_backup_scene.h"
@@ -44,6 +45,7 @@ class RuntimeBackup {
   /* Restore fields to the given ID. */
   void restore_to_id(ID *id);
 
+  AnimationBackup animation_backup;
   SceneBackup scene_backup;
   SoundBackup sound_backup;
   ObjectRuntimeBackup object_backup;
diff --git a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.cc b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.cc
new file mode 100644
index 00000000000..0a6f0641fcf
--- /dev/null
+++ b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.cc
@@ -0,0 +1,139 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2019 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup depsgraph
+ */
+
+#include "intern/eval/deg_eval_runtime_backup_animation.h"
+
+#include "DNA_anim_types.h"
+
+#include "BKE_animsys.h"
+
+#include "RNA_access.h"
+#include "RNA_types.h"
+
+#include "intern/depsgraph.h"
+
+namespace DEG {
+
+namespace {
+
+struct AnimatedPropertyStoreCalbackData {
+  AnimationBackup *backup;
+
+  /* ID which needs to be stored.
+   * Is used to check possibly nested IDs which f-curves are pointing to. */
+  ID *id;
+
+  PointerRNA id_pointer_rna;
+};
+
+void animated_property_store_cb(ID *id, FCurve *fcurve, void *data_v)
+{
+  AnimatedPropertyStoreCalbackData *data = reinterpret_cast<AnimatedPropertyStoreCalbackData *>(
+      data_v);
+  if (fcurve->rna_path == NULL || fcurve->rna_path[0] == '\0') {
+    return;
+  }
+  if (id != data->id) {
+    return;
+  }
+
+  /* Resolve path to the property. */
+  PathResolvedRNA resolved_rna;
+  if (!RNA_path_resolve_property_full(&data->id_pointer_rna,
+                                      fcurve->rna_path,
+                                      &resolved_rna.ptr,
+                                      &resolved_rna.prop,
+                                      &resolved_rna.prop_index)) {
+    return;
+  }
+
+  /* Read property value. */
+  float value;
+  if (!BKE_animsys_read_rna_setting(&resolved_rna, &value)) {
+    return;
+  }
+
+  data->backup->values_backup.emplace_back(fcurve->rna_path, value);
+}
+
+}  // namespace
+
+AnimationValueBackup::AnimationValueBackup()
+{
+}
+
+AnimationValueBackup::AnimationValueBackup(const string &rna_path, float value)
+    : rna_path(rna_path), value(value)
+{
+}
+
+AnimationValueBackup::~AnimationValueBackup()
+{
+}
+
+AnimationBackup::AnimationBackup(const Depsgraph *depsgraph)
+{
+  meed_value_backup = !depsgraph->is_active;
+  reset();
+}
+
+void AnimationBackup::reset()
+{
+}
+
+void AnimationBackup::init_from_id(ID *id)
+{
+  AnimatedPropertyStoreCalbackData data;
+  data.backup = this;
+  data.id = id;
+  RNA_id_pointer_create(id, &data.id_pointer_rna);
+  BKE_fcurves_id_cb(id, animated_property_store_cb, &data);
+}
+
+void AnimationBackup::restore_to_id(ID *id)
+{
+  PointerRNA id_pointer_rna;
+  RNA_id_pointer_create(id, &id_pointer_rna);
+  for (const AnimationValueBackup &value_backup : values_backup) {
+    /* Resolve path to the property.
+     *
+     * NOTE: Do it again (after storing), since the sub-data [ointers might be
+     * changed after copy-on-write.
+     */
+    PathResolvedRNA resolved_rna;
+    if (!RNA_path_resolve_property_full(&id_pointer_rna,
+                                        value_backup.rna_path.c_str(),
+                                        &resolved_rna.ptr,
+                                        &resolved_rna.prop,
+                                        &resolved_rna.prop_index)) {
+      return;
+    }
+
+    /* Write property value. */
+    if (!BKE_animsys_write_rna_setting(&resolved_rna, value_backup.value)) {
+      return;
+    }
+  }
+}
+
+}  // namespace DEG
diff --git a/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.h b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.h
new file mode 100644
index 00000000000..8c111107f36
--- /dev/null
+++ b/source/blender/depsgraph/intern/eval/deg_eval_runtime_backup_animation.h
@@ -0,0 +1,64 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2019 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup depsgraph
+ */
+
+#pragma once
+
+#include "BKE_modifier.h"
+
+#include "intern/depsgraph_type.h"
+
+namespace DEG {
+
+struct Depsgraph;
+
+class AnimationValueBackup {
+ public:
+  AnimationValueBackup();
+  AnimationValueBackup(const string &rna_path, float value);
+  ~AnimationValueBackup();
+
+  AnimationValueBackup(const AnimationValueBackup &other) = default;
+  AnimationValueBackup(AnimationValueBackup &&other) noexcept = default;
+
+  AnimationValueBackup &operator=(const AnimationValueBackup &other) = default;
+  AnimationValueBackup &operator=(AnimationValueBackup &&other) = default;
+
+  string rna_path;
+  float value;
+};
+
+/* Backup of animated properties values. */
+class AnimationBackup {
+ public:
+  AnimationBackup(const Depsgraph *depsgraph);
+
+  void reset();
+
+  void init_from_id(ID *id);
+  void restore_to_id(ID *id);
+
+  bool meed_value_backup;
+  vector<AnimationValueBackup> values_backup;
+};
+
+}  // namespace DEG