4 files changed, 85 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_ui/space_nla.py b/release/scripts/startup/bl_ui/space_nla.py
index ae5d308b0d3..06fe73a543c 100644
--- a/release/scripts/startup/bl_ui/space_nla.py
+++ b/release/scripts/startup/bl_ui/space_nla.py
@@ -147,6 +147,9 @@ class NLA_MT_edit(Menu):
         layout.operator("nla.action_sync_length").active = False
 
         layout.separator()
+        layout.operator("nla.make_single_user")
+
+        layout.separator()
         layout.operator("nla.swap")
         layout.operator("nla.move_up")
         layout.operator("nla.move_down")
diff --git a/source/blender/editors/space_nla/nla_edit.c b/source/blender/editors/space_nla/nla_edit.c
index bb1e0e4245f..4eea5de616c 100644
--- a/source/blender/editors/space_nla/nla_edit.c
+++ b/source/blender/editors/space_nla/nla_edit.c
@@ -49,6 +49,7 @@
 #include "BKE_fcurve.h"
 #include "BKE_nla.h"
 #include "BKE_context.h"
+#include "BKE_library.h"
 #include "BKE_main.h"
 #include "BKE_report.h"
 #include "BKE_screen.h"
@@ -1709,6 +1710,80 @@ void NLA_OT_action_sync_length(wmOperatorType *ot)
 	ot->prop = RNA_def_boolean(ot->srna, "active", 1, "Active Strip Only", "Only sync the active length for the active strip");
 }
 
+/* ******************** Make Single User ********************************* */
+/* Ensure that each strip has its own action */
+
+static int nlaedit_make_single_user_exec(bContext *C, wmOperator *UNUSED(op))
+{
+	bAnimContext ac;
+	
+	ListBase anim_data = {NULL, NULL};
+	bAnimListElem *ale;
+	int filter;
+	
+	/* get editor data */
+	if (ANIM_animdata_get_context(C, &ac) == 0)
+		return OPERATOR_CANCELLED;
+		
+	/* get a list of the editable tracks being shown in the NLA */
+	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_FOREDIT);
+	ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+	
+	/* Ensure that each action used only has a single user
+	 *   - This is done in reverse order so that the original strips are
+	 *     likely to still get to keep their action
+	 */
+	for (ale = anim_data.last; ale; ale = ale->prev) {
+		NlaTrack *nlt = (NlaTrack *)ale->data;
+		NlaStrip *strip;
+		
+		for (strip = nlt->strips.last; strip; strip = strip->prev) {
+			/* must be action-clip only (as only these have actions) */
+			if ((strip->flag & NLASTRIP_FLAG_SELECT) && (strip->type == NLASTRIP_TYPE_CLIP)) {
+				if (strip->act == NULL) 
+					continue;
+				
+				/* multi-user? */
+				if (ID_REAL_USERS(strip->act) > 1) {
+					/* make a new copy of the action for us to use (it will have 1 user already) */
+					bAction *new_action = BKE_action_copy(strip->act);
+					
+					/* decrement user count of our existing action */
+					id_us_min(&strip->act->id);
+					
+					/* switch to the new copy */
+					strip->act = new_action;
+				}
+			}
+		}
+	}
+	
+	/* free temp data */
+	BLI_freelistN(&anim_data);
+	
+	/* set notifier that things have changed */
+	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+	
+	/* done */
+	return OPERATOR_FINISHED;
+}
+
+void NLA_OT_make_single_user(wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name = "Make Single User";
+	ot->idname = "NLA_OT_make_single_user";
+	ot->description = "Ensure that each action is only used once in the set of strips selected";
+	
+	/* api callbacks */
+	ot->invoke = WM_operator_confirm;
+	ot->exec = nlaedit_make_single_user_exec;
+	ot->poll = nlaop_poll_tweakmode_off;
+	
+	/* flags */
+	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
 /* ******************** Apply Scale Operator ***************************** */
 /* Reset the scaling of the selected strips to 1.0f */
 
diff --git a/source/blender/editors/space_nla/nla_intern.h b/source/blender/editors/space_nla/nla_intern.h
index 8d49d54375a..ad1a4dfa432 100644
--- a/source/blender/editors/space_nla/nla_intern.h
+++ b/source/blender/editors/space_nla/nla_intern.h
@@ -112,6 +112,8 @@ void NLA_OT_move_down(wmOperatorType *ot);
 
 void NLA_OT_action_sync_length(wmOperatorType *ot);
 
+void NLA_OT_make_single_user(wmOperatorType *ot);
+
 void NLA_OT_apply_scale(wmOperatorType *ot);
 void NLA_OT_clear_scale(wmOperatorType *ot);
 
diff --git a/source/blender/editors/space_nla/nla_ops.c b/source/blender/editors/space_nla/nla_ops.c
index 9dc598bc382..47496684380 100644
--- a/source/blender/editors/space_nla/nla_ops.c
+++ b/source/blender/editors/space_nla/nla_ops.c
@@ -158,6 +158,8 @@ void nla_operatortypes(void)
 	
 	WM_operatortype_append(NLA_OT_action_sync_length);
 	
+	WM_operatortype_append(NLA_OT_make_single_user);
+	
 	WM_operatortype_append(NLA_OT_apply_scale);
 	WM_operatortype_append(NLA_OT_clear_scale);
 	
@@ -261,6 +263,9 @@ static void nla_keymap_main(wmKeyConfig *keyconf, wmKeyMap *keymap)
 	
 	kmi = WM_keymap_add_item(keymap, "NLA_OT_duplicate", DKEY, KM_PRESS, KM_ALT, 0);
 	RNA_boolean_set(kmi->ptr, "linked", true);
+	
+	/* single user */
+	WM_keymap_add_item(keymap, "NLA_OT_make_single_user", UKEY, KM_PRESS, 0, 0);
 		
 	/* delete */
 	WM_keymap_add_item(keymap, "NLA_OT_delete", XKEY, KM_PRESS, 0, 0);