3 files changed, 142 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_armature.h b/source/blender/blenkernel/BKE_armature.h
index db44a771095..f5face2120e 100644
--- a/source/blender/blenkernel/BKE_armature.h
+++ b/source/blender/blenkernel/BKE_armature.h
@@ -27,6 +27,8 @@
 extern "C" {
 #endif
 
+struct AnimationEvalContext;
+struct bAction;
 struct BMEditMesh;
 struct Bone;
 struct Depsgraph;
@@ -193,6 +195,12 @@ void BKE_pose_where_is_bone(struct Depsgraph *depsgraph,
                             bool do_extra);
 void BKE_pose_where_is_bone_tail(struct bPoseChannel *pchan);
 
+/* Evaluate the action and apply it to the pose. If any pose bones are selected, only FCurves that
+ * relate to those bones are evaluated. */
+void BKE_pose_apply_action(struct Object *ob,
+                           struct bAction *action,
+                           struct AnimationEvalContext *anim_eval_context);
+
 /* get_objectspace_bone_matrix has to be removed still */
 void get_objectspace_bone_matrix(struct Bone *bone,
                                  float M_accumulatedMatrix[4][4],
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 1e7986eedd9..c954d0670f0 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -77,6 +77,7 @@ set(SRC
   intern/appdir.c
   intern/armature.c
   intern/armature_deform.c
+  intern/armature_pose.cc
   intern/armature_update.c
   intern/asset.cc
   intern/attribute.c
diff --git a/source/blender/blenkernel/intern/armature_pose.cc b/source/blender/blenkernel/intern/armature_pose.cc
new file mode 100644
index 00000000000..a9613da2335
--- /dev/null
+++ b/source/blender/blenkernel/intern/armature_pose.cc
@@ -0,0 +1,133 @@
+/*
+ * 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) 2015 Blender Foundation.
+ * All rights reserved.
+ *
+ * Defines and code for core node types
+ */
+
+/** \file
+ * \ingroup bke
+ */
+
+#include "BKE_animsys.h"
+#include "BKE_armature.h"
+
+#include "BLI_set.hh"
+
+#include "DNA_action_types.h"
+#include "DNA_anim_types.h"
+#include "DNA_armature_types.h"
+#include "DNA_object_types.h"
+
+#include "RNA_access.h"
+
+namespace {
+using BoneNameSet = blender::Set<std::string>;
+
+// Forward declarations.
+BoneNameSet pose_apply_find_selected_bones(const bPose *pose);
+void pose_apply_disable_fcurves_for_unselected_bones(bAction *action,
+                                                     const BoneNameSet &selected_bone_names);
+void pose_apply_restore_fcurves(bAction *action);
+}  // namespace
+
+void BKE_pose_apply_action(struct Object *ob,
+                           struct bAction *action,
+                           struct AnimationEvalContext *anim_eval_context)
+{
+  bPose *pose = ob->pose;
+  if (pose == NULL) {
+    return;
+  }
+
+  const BoneNameSet selected_bone_names = pose_apply_find_selected_bones(pose);
+  const bool limit_to_selected_bones = !selected_bone_names.is_empty();
+
+  if (limit_to_selected_bones) {
+    /* Mute all FCurves that are not associated with selected bones. This separates the concept of
+     * bone selection from the FCurve evaluation code. */
+    pose_apply_disable_fcurves_for_unselected_bones(action, selected_bone_names);
+  }
+
+  /* Apply the Action. */
+  PointerRNA pose_owner_ptr;
+  RNA_id_pointer_create(&ob->id, &pose_owner_ptr);
+  animsys_evaluate_action(&pose_owner_ptr, action, anim_eval_context, false);
+
+  if (limit_to_selected_bones) {
+    pose_apply_restore_fcurves(action);
+  }
+}
+
+namespace {
+BoneNameSet pose_apply_find_selected_bones(const bPose *pose)
+{
+  BoneNameSet selected_bone_names;
+  bool all_bones_selected = true;
+  bool no_bones_selected = true;
+
+  LISTBASE_FOREACH (bPoseChannel *, pchan, &pose->chanbase) {
+    const bool is_selected = (pchan->bone->flag & BONE_SELECTED) != 0 &&
+                             (pchan->bone->flag & BONE_HIDDEN_P) == 0;
+    all_bones_selected &= is_selected;
+    no_bones_selected &= !is_selected;
+
+    if (is_selected) {
+      /* Bone names are unique, so no need to check for duplicates. */
+      selected_bone_names.add_new(pchan->name);
+    }
+  }
+
+  /* If no bones are selected, act as if all are. */
+  if (all_bones_selected || no_bones_selected) {
+    return BoneNameSet(); /* An empty set means "ignore bone selection". */
+  }
+  return selected_bone_names;
+}
+
+void pose_apply_restore_fcurves(bAction *action)
+{
+  /* TODO(Sybren): Restore the FCurve flags, instead of just erasing the 'disabled' flag. */
+  LISTBASE_FOREACH (FCurve *, fcu, &action->curves) {
+    fcu->flag &= ~FCURVE_DISABLED;
+  }
+}
+
+void pose_apply_disable_fcurves_for_unselected_bones(bAction *action,
+                                                     const BoneNameSet &selected_bone_names)
+{
+  LISTBASE_FOREACH (FCurve *, fcu, &action->curves) {
+    if (!fcu->rna_path || !strstr(fcu->rna_path, "pose.bones[")) {
+      continue;
+    }
+
+    /* Get bone name, and check if this bone is selected. */
+    char *bone_name = BLI_str_quoted_substrN(fcu->rna_path, "pose.bones[");
+    if (!bone_name) {
+      continue;
+    }
+    const bool is_selected = selected_bone_names.contains(bone_name);
+    MEM_freeN(bone_name);
+    if (is_selected) {
+      continue;
+    }
+
+    fcu->flag |= FCURVE_DISABLED;
+  }
+}
+
+}  // namespace