ClangFormat: apply to source, most of intern

Apply clang format as proposed in T53211.

For details on usage and instructions for migrating branches
without conflicts, see:

https://wiki.blender.org/wiki/Tools/ClangFormat

1 files changed, 2023 insertions, 1973 deletions

diff --git a/source/blender/editors/space_nla/nla_edit.c b/source/blender/editors/space_nla/nla_edit.c
index 1d21619fbd1..79c2242cd01 100644
--- a/source/blender/editors/space_nla/nla_edit.c
+++ b/source/blender/editors/space_nla/nla_edit.c
@@ -21,7 +21,6 @@
  * \ingroup spnla
  */
 
-
 #include <string.h>
 #include <stdio.h>
 #include <math.h>
@@ -66,8 +65,8 @@
 #include "UI_resources.h"
 #include "UI_view2d.h"
 
-#include "nla_intern.h" // own include
-#include "nla_private.h" // FIXME... maybe this shouldn't be included?
+#include "nla_intern.h"   // own include
+#include "nla_private.h"  // FIXME... maybe this shouldn't be included?
 
 /* *********************************************** */
 /* Utilities exported to other places... */
@@ -75,23 +74,23 @@
 /* Perform validation for blending/extend settings */
 void ED_nla_postop_refresh(bAnimContext *ac)
 {
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	short filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA | ANIMFILTER_FOREDIT);
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  short filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA | ANIMFILTER_FOREDIT);
 
-	/* get blocks to work on */
-	ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
+  /* get blocks to work on */
+  ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
 
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		/* performing auto-blending, extend-mode validation, etc. */
-		BKE_nla_validate_state(ale->data);
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    /* performing auto-blending, extend-mode validation, etc. */
+    BKE_nla_validate_state(ale->data);
 
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
 
-	/* free temp memory */
-	ANIM_animdata_update(ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp memory */
+  ANIM_animdata_update(ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
 }
 
 /* *********************************************** */
@@ -104,92 +103,96 @@ void ED_nla_postop_refresh(bAnimContext *ac)
 
 static int nlaedit_enable_tweakmode_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	const bool do_solo = RNA_boolean_get(op->ptr, "isolate_action");
-	bool ok = false;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-
-	/* get a list of the AnimData blocks being shown in the NLA */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA);
-	ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
-
-	/* if no blocks, popup error? */
-	if (BLI_listbase_is_empty(&anim_data)) {
-		BKE_report(op->reports, RPT_ERROR, "No AnimData blocks to enter tweak mode for");
-		return OPERATOR_CANCELLED;
-	}
-
-	/* for each AnimData block with NLA-data, try setting it in tweak-mode */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		AnimData *adt = ale->data;
-
-		/* try entering tweakmode if valid */
-		ok |= BKE_nla_tweakmode_enter(adt);
-
-		/* mark the active track as being "solo"? */
-		if (do_solo && adt->actstrip) {
-			NlaTrack *nlt = BKE_nlatrack_find_tweaked(adt);
-
-			if (nlt && !(nlt->flag & NLATRACK_SOLO)) {
-				BKE_nlatrack_solo_toggle(adt, nlt);
-			}
-		}
-
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* if we managed to enter tweakmode on at least one AnimData block,
-	 * set the flag for this in the active scene and send notifiers
-	 */
-	if (ac.scene && ok) {
-		/* set editing flag */
-		ac.scene->flag |= SCE_NLA_EDIT_ON;
-
-		/* set notifier that things have changed */
-		WM_event_add_notifier(C, NC_ANIMATION | ND_NLA_ACTCHANGE, NULL);
-	}
-	else {
-		BKE_report(op->reports, RPT_ERROR, "No active strip(s) to enter tweak mode on");
-		return OPERATOR_CANCELLED;
-	}
-
-	/* done */
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  const bool do_solo = RNA_boolean_get(op->ptr, "isolate_action");
+  bool ok = false;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+
+  /* get a list of the AnimData blocks being shown in the NLA */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA);
+  ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+
+  /* if no blocks, popup error? */
+  if (BLI_listbase_is_empty(&anim_data)) {
+    BKE_report(op->reports, RPT_ERROR, "No AnimData blocks to enter tweak mode for");
+    return OPERATOR_CANCELLED;
+  }
+
+  /* for each AnimData block with NLA-data, try setting it in tweak-mode */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    AnimData *adt = ale->data;
+
+    /* try entering tweakmode if valid */
+    ok |= BKE_nla_tweakmode_enter(adt);
+
+    /* mark the active track as being "solo"? */
+    if (do_solo && adt->actstrip) {
+      NlaTrack *nlt = BKE_nlatrack_find_tweaked(adt);
+
+      if (nlt && !(nlt->flag & NLATRACK_SOLO)) {
+        BKE_nlatrack_solo_toggle(adt, nlt);
+      }
+    }
+
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  /* if we managed to enter tweakmode on at least one AnimData block,
+   * set the flag for this in the active scene and send notifiers
+   */
+  if (ac.scene && ok) {
+    /* set editing flag */
+    ac.scene->flag |= SCE_NLA_EDIT_ON;
+
+    /* set notifier that things have changed */
+    WM_event_add_notifier(C, NC_ANIMATION | ND_NLA_ACTCHANGE, NULL);
+  }
+  else {
+    BKE_report(op->reports, RPT_ERROR, "No active strip(s) to enter tweak mode on");
+    return OPERATOR_CANCELLED;
+  }
+
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_tweakmode_enter(wmOperatorType *ot)
 {
-	PropertyRNA *prop;
-
-	/* identifiers */
-	ot->name = "Enter Tweak Mode";
-	ot->idname = "NLA_OT_tweakmode_enter";
-	ot->description = "Enter tweaking mode for the action referenced by the active strip to edit its keyframes";
-
-	/* api callbacks */
-	ot->exec = nlaedit_enable_tweakmode_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* properties */
-	prop = RNA_def_boolean(ot->srna, "isolate_action", 0, "Isolate Action",
-	                       "Enable 'solo' on the NLA Track containing the active strip, "
-	                       "to edit it without seeing the effects of the NLA stack");
-	RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  PropertyRNA *prop;
+
+  /* identifiers */
+  ot->name = "Enter Tweak Mode";
+  ot->idname = "NLA_OT_tweakmode_enter";
+  ot->description =
+      "Enter tweaking mode for the action referenced by the active strip to edit its keyframes";
+
+  /* api callbacks */
+  ot->exec = nlaedit_enable_tweakmode_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* properties */
+  prop = RNA_def_boolean(ot->srna,
+                         "isolate_action",
+                         0,
+                         "Isolate Action",
+                         "Enable 'solo' on the NLA Track containing the active strip, "
+                         "to edit it without seeing the effects of the NLA stack");
+  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 }
 
 /* ------------- */
@@ -197,99 +200,100 @@ void NLA_OT_tweakmode_enter(wmOperatorType *ot)
 /* NLA Editor internal API function for exiting tweakmode */
 bool nlaedit_disable_tweakmode(bAnimContext *ac, bool do_solo)
 {
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	/* get a list of the AnimData blocks being shown in the NLA */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA);
-	ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
-
-	/* if no blocks, popup error? */
-	if (BLI_listbase_is_empty(&anim_data)) {
-		BKE_report(ac->reports, RPT_ERROR, "No AnimData blocks in tweak mode to exit from");
-		return false;
-	}
-
-	/* for each AnimData block with NLA-data, try exitting tweak-mode */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		AnimData *adt = ale->data;
-
-		/* clear solo flags */
-		if ((do_solo) & (adt->flag & ADT_NLA_SOLO_TRACK) &&
-		    (adt->flag & ADT_NLA_EDIT_ON))
-		{
-			BKE_nlatrack_solo_toggle(adt, NULL);
-		}
-
-		/* to be sure that we're doing everything right, just exit tweakmode... */
-		BKE_nla_tweakmode_exit(adt);
-
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* if we managed to enter tweakmode on at least one AnimData block,
-	 * set the flag for this in the active scene and send notifiers
-	 */
-	if (ac->scene) {
-		/* clear editing flag */
-		ac->scene->flag &= ~SCE_NLA_EDIT_ON;
-
-		/* set notifier that things have changed */
-		WM_main_add_notifier(NC_ANIMATION | ND_NLA_ACTCHANGE, NULL);
-	}
-
-	/* done */
-	return true;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  /* get a list of the AnimData blocks being shown in the NLA */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ANIMDATA);
+  ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
+
+  /* if no blocks, popup error? */
+  if (BLI_listbase_is_empty(&anim_data)) {
+    BKE_report(ac->reports, RPT_ERROR, "No AnimData blocks in tweak mode to exit from");
+    return false;
+  }
+
+  /* for each AnimData block with NLA-data, try exitting tweak-mode */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    AnimData *adt = ale->data;
+
+    /* clear solo flags */
+    if ((do_solo) & (adt->flag & ADT_NLA_SOLO_TRACK) && (adt->flag & ADT_NLA_EDIT_ON)) {
+      BKE_nlatrack_solo_toggle(adt, NULL);
+    }
+
+    /* to be sure that we're doing everything right, just exit tweakmode... */
+    BKE_nla_tweakmode_exit(adt);
+
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  /* if we managed to enter tweakmode on at least one AnimData block,
+   * set the flag for this in the active scene and send notifiers
+   */
+  if (ac->scene) {
+    /* clear editing flag */
+    ac->scene->flag &= ~SCE_NLA_EDIT_ON;
+
+    /* set notifier that things have changed */
+    WM_main_add_notifier(NC_ANIMATION | ND_NLA_ACTCHANGE, NULL);
+  }
+
+  /* done */
+  return true;
 }
 
 /* exit tweakmode operator callback */
 static int nlaedit_disable_tweakmode_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	const bool do_solo = RNA_boolean_get(op->ptr, "isolate_action");
-	bool ok = false;
+  const bool do_solo = RNA_boolean_get(op->ptr, "isolate_action");
+  bool ok = false;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
 
-	/* perform operation */
-	ok = nlaedit_disable_tweakmode(&ac, do_solo);
+  /* perform operation */
+  ok = nlaedit_disable_tweakmode(&ac, do_solo);
 
-	/* success? */
-	if (ok)
-		return OPERATOR_FINISHED;
-	else
-		return OPERATOR_CANCELLED;
+  /* success? */
+  if (ok)
+    return OPERATOR_FINISHED;
+  else
+    return OPERATOR_CANCELLED;
 }
 
 void NLA_OT_tweakmode_exit(wmOperatorType *ot)
 {
-	PropertyRNA *prop;
-
-	/* identifiers */
-	ot->name = "Exit Tweak Mode";
-	ot->idname = "NLA_OT_tweakmode_exit";
-	ot->description = "Exit tweaking mode for the action referenced by the active strip";
-
-	/* api callbacks */
-	ot->exec = nlaedit_disable_tweakmode_exec;
-	ot->poll = nlaop_poll_tweakmode_on;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* properties */
-	prop = RNA_def_boolean(ot->srna, "isolate_action", 0, "Isolate Action",
-	                       "Disable 'solo' on any of the NLA Tracks after exiting tweak mode "
-	                       "to get things back to normal");
-	RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+  PropertyRNA *prop;
+
+  /* identifiers */
+  ot->name = "Exit Tweak Mode";
+  ot->idname = "NLA_OT_tweakmode_exit";
+  ot->description = "Exit tweaking mode for the action referenced by the active strip";
+
+  /* api callbacks */
+  ot->exec = nlaedit_disable_tweakmode_exec;
+  ot->poll = nlaop_poll_tweakmode_on;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* properties */
+  prop = RNA_def_boolean(ot->srna,
+                         "isolate_action",
+                         0,
+                         "Isolate Action",
+                         "Disable 'solo' on any of the NLA Tracks after exiting tweak mode "
+                         "to get things back to normal");
+  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 }
 
 /* *********************************************** */
@@ -300,98 +304,98 @@ void NLA_OT_tweakmode_exit(wmOperatorType *ot)
 /* Get the min/max strip extents */
 static void get_nlastrip_extents(bAnimContext *ac, float *min, float *max, const bool only_sel)
 {
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-	bool found_bounds = false;
-
-	/* get data to filter */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_NODUPLIS);
-	ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
-
-	/* set large values to try to override */
-	*min = 999999999.0f;
-	*max = -999999999.0f;
-
-	/* check if any channels to set range with */
-	if (anim_data.first) {
-		/* go through channels, finding max extents */
-		for (ale = anim_data.first; ale; ale = ale->next) {
-			NlaTrack *nlt = (NlaTrack *)ale->data;
-			NlaStrip *strip;
-
-			for (strip = nlt->strips.first; strip; strip = strip->next) {
-				/* only consider selected strips? */
-				if ((only_sel == false) || (strip->flag & NLASTRIP_FLAG_SELECT)) {
-					/* extend range if appropriate */
-					*min = min_ff(*min, strip->start);
-					*max = max_ff(*max, strip->end);
-
-					found_bounds = true;
-				}
-			}
-		}
-
-		/* free memory */
-		ANIM_animdata_freelist(&anim_data);
-	}
-
-	/* set default range if nothing happened */
-	if (found_bounds == false) {
-		if (ac->scene) {
-			*min = (float)ac->scene->r.sfra;
-			*max = (float)ac->scene->r.efra;
-		}
-		else {
-			*min = -5;
-			*max = 100;
-		}
-	}
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+  bool found_bounds = false;
+
+  /* get data to filter */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_NODUPLIS);
+  ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
+
+  /* set large values to try to override */
+  *min = 999999999.0f;
+  *max = -999999999.0f;
+
+  /* check if any channels to set range with */
+  if (anim_data.first) {
+    /* go through channels, finding max extents */
+    for (ale = anim_data.first; ale; ale = ale->next) {
+      NlaTrack *nlt = (NlaTrack *)ale->data;
+      NlaStrip *strip;
+
+      for (strip = nlt->strips.first; strip; strip = strip->next) {
+        /* only consider selected strips? */
+        if ((only_sel == false) || (strip->flag & NLASTRIP_FLAG_SELECT)) {
+          /* extend range if appropriate */
+          *min = min_ff(*min, strip->start);
+          *max = max_ff(*max, strip->end);
+
+          found_bounds = true;
+        }
+      }
+    }
+
+    /* free memory */
+    ANIM_animdata_freelist(&anim_data);
+  }
+
+  /* set default range if nothing happened */
+  if (found_bounds == false) {
+    if (ac->scene) {
+      *min = (float)ac->scene->r.sfra;
+      *max = (float)ac->scene->r.efra;
+    }
+    else {
+      *min = -5;
+      *max = 100;
+    }
+  }
 }
 
 /* ****************** Automatic Preview-Range Operator ****************** */
 
 static int nlaedit_previewrange_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
-	Scene *scene;
-	float min, max;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-
-	if (ac.scene == NULL)
-		return OPERATOR_CANCELLED;
-	else
-		scene = ac.scene;
-
-	/* set the range directly */
-	get_nlastrip_extents(&ac, &min, &max, true);
-	scene->r.flag |= SCER_PRV_RANGE;
-	scene->r.psfra = round_fl_to_int(min);
-	scene->r.pefra = round_fl_to_int(max);
-
-	/* set notifier that things have changed */
-	// XXX err... there's nothing for frame ranges yet, but this should do fine too
-	WM_event_add_notifier(C, NC_SCENE | ND_FRAME, ac.scene);
-
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+  Scene *scene;
+  float min, max;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+
+  if (ac.scene == NULL)
+    return OPERATOR_CANCELLED;
+  else
+    scene = ac.scene;
+
+  /* set the range directly */
+  get_nlastrip_extents(&ac, &min, &max, true);
+  scene->r.flag |= SCER_PRV_RANGE;
+  scene->r.psfra = round_fl_to_int(min);
+  scene->r.pefra = round_fl_to_int(max);
+
+  /* set notifier that things have changed */
+  // XXX err... there's nothing for frame ranges yet, but this should do fine too
+  WM_event_add_notifier(C, NC_SCENE | ND_FRAME, ac.scene);
+
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_previewrange_set(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Auto-Set Preview Range";
-	ot->idname = "NLA_OT_previewrange_set";
-	ot->description = "Automatically set Preview Range based on range of keyframes";
+  /* identifiers */
+  ot->name = "Auto-Set Preview Range";
+  ot->idname = "NLA_OT_previewrange_set";
+  ot->description = "Automatically set Preview Range based on range of keyframes";
 
-	/* api callbacks */
-	ot->exec = nlaedit_previewrange_exec;
-	ot->poll = ED_operator_nla_active;
+  /* api callbacks */
+  ot->exec = nlaedit_previewrange_exec;
+  ot->poll = ED_operator_nla_active;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ****************** View-All Operator ****************** */
@@ -405,170 +409,169 @@ void NLA_OT_previewrange_set(wmOperatorType *ot)
  */
 static bool nla_channels_get_selected_extents(bAnimContext *ac, float *min, float *max)
 {
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	SpaceNla *snla = (SpaceNla *)ac->sl;
-	const float half_height = NLACHANNEL_HEIGHT_HALF(snla);
-	/* NOTE: not bool, since we want prioritise individual channels over expanders */
-	short found = 0;
-	float y;
-
-	/* get all items - we need to do it this way */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_LIST_CHANNELS);
-	ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
-
-	/* loop through all channels, finding the first one that's selected */
-	y = (float)NLACHANNEL_FIRST;
-
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		const bAnimChannelType *acf = ANIM_channel_get_typeinfo(ale);
-
-		/* must be selected... */
-		if (acf && acf->has_setting(ac, ale, ACHANNEL_SETTING_SELECT) &&
-		    ANIM_channel_setting_get(ac, ale, ACHANNEL_SETTING_SELECT))
-		{
-			/* update best estimate */
-			*min = (float)(y - half_height);
-			*max = (float)(y + half_height);
-
-			/* is this high enough priority yet? */
-			found = acf->channel_role;
-
-			/* only stop our search when we've found an actual channel
-			 * - datablock expanders get less priority so that we don't abort prematurely
-			 */
-			if (found == ACHANNEL_ROLE_CHANNEL) {
-				break;
-			}
-		}
-
-		/* adjust y-position for next one */
-		y -= NLACHANNEL_STEP(snla);
-	}
-
-	/* free all temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	return (found != 0);
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  SpaceNla *snla = (SpaceNla *)ac->sl;
+  const float half_height = NLACHANNEL_HEIGHT_HALF(snla);
+  /* NOTE: not bool, since we want prioritise individual channels over expanders */
+  short found = 0;
+  float y;
+
+  /* get all items - we need to do it this way */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_LIST_CHANNELS);
+  ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
+
+  /* loop through all channels, finding the first one that's selected */
+  y = (float)NLACHANNEL_FIRST;
+
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    const bAnimChannelType *acf = ANIM_channel_get_typeinfo(ale);
+
+    /* must be selected... */
+    if (acf && acf->has_setting(ac, ale, ACHANNEL_SETTING_SELECT) &&
+        ANIM_channel_setting_get(ac, ale, ACHANNEL_SETTING_SELECT)) {
+      /* update best estimate */
+      *min = (float)(y - half_height);
+      *max = (float)(y + half_height);
+
+      /* is this high enough priority yet? */
+      found = acf->channel_role;
+
+      /* only stop our search when we've found an actual channel
+       * - datablock expanders get less priority so that we don't abort prematurely
+       */
+      if (found == ACHANNEL_ROLE_CHANNEL) {
+        break;
+      }
+    }
+
+    /* adjust y-position for next one */
+    y -= NLACHANNEL_STEP(snla);
+  }
+
+  /* free all temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  return (found != 0);
 }
 
 static int nlaedit_viewall(bContext *C, const bool only_sel)
 {
-	bAnimContext ac;
-	View2D *v2d;
-	float extra;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-	v2d = &ac.ar->v2d;
-
-	/* set the horizontal range, with an extra offset so that the extreme keys will be in view */
-	get_nlastrip_extents(&ac, &v2d->cur.xmin, &v2d->cur.xmax, only_sel);
-
-	extra = 0.1f * BLI_rctf_size_x(&v2d->cur);
-	v2d->cur.xmin -= extra;
-	v2d->cur.xmax += extra;
-
-	/* set vertical range */
-	if (only_sel == false) {
-		/* view all -> the summary channel is usually the shows everything,
-		 * and resides right at the top... */
-		v2d->cur.ymax = 0.0f;
-		v2d->cur.ymin = (float)-BLI_rcti_size_y(&v2d->mask);
-	}
-	else {
-		/* locate first selected channel (or the active one), and frame those */
-		float ymin = v2d->cur.ymin;
-		float ymax = v2d->cur.ymax;
-
-		if (nla_channels_get_selected_extents(&ac, &ymin, &ymax)) {
-			/* recenter the view so that this range is in the middle */
-			float ymid = (ymax - ymin) / 2.0f + ymin;
-			float x_center;
-
-			UI_view2d_center_get(v2d, &x_center, NULL);
-			UI_view2d_center_set(v2d, x_center, ymid);
-		}
-	}
-
-	/* do View2D syncing */
-	UI_view2d_sync(CTX_wm_screen(C), CTX_wm_area(C), v2d, V2D_LOCK_COPY);
-
-	/* just redraw this view */
-	ED_area_tag_redraw(CTX_wm_area(C));
-
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+  View2D *v2d;
+  float extra;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+  v2d = &ac.ar->v2d;
+
+  /* set the horizontal range, with an extra offset so that the extreme keys will be in view */
+  get_nlastrip_extents(&ac, &v2d->cur.xmin, &v2d->cur.xmax, only_sel);
+
+  extra = 0.1f * BLI_rctf_size_x(&v2d->cur);
+  v2d->cur.xmin -= extra;
+  v2d->cur.xmax += extra;
+
+  /* set vertical range */
+  if (only_sel == false) {
+    /* view all -> the summary channel is usually the shows everything,
+     * and resides right at the top... */
+    v2d->cur.ymax = 0.0f;
+    v2d->cur.ymin = (float)-BLI_rcti_size_y(&v2d->mask);
+  }
+  else {
+    /* locate first selected channel (or the active one), and frame those */
+    float ymin = v2d->cur.ymin;
+    float ymax = v2d->cur.ymax;
+
+    if (nla_channels_get_selected_extents(&ac, &ymin, &ymax)) {
+      /* recenter the view so that this range is in the middle */
+      float ymid = (ymax - ymin) / 2.0f + ymin;
+      float x_center;
+
+      UI_view2d_center_get(v2d, &x_center, NULL);
+      UI_view2d_center_set(v2d, x_center, ymid);
+    }
+  }
+
+  /* do View2D syncing */
+  UI_view2d_sync(CTX_wm_screen(C), CTX_wm_area(C), v2d, V2D_LOCK_COPY);
+
+  /* just redraw this view */
+  ED_area_tag_redraw(CTX_wm_area(C));
+
+  return OPERATOR_FINISHED;
 }
 
 /* ......... */
 
 static int nlaedit_viewall_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	/* whole range */
-	return nlaedit_viewall(C, false);
+  /* whole range */
+  return nlaedit_viewall(C, false);
 }
 
 static int nlaedit_viewsel_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	/* only selected */
-	return nlaedit_viewall(C, true);
+  /* only selected */
+  return nlaedit_viewall(C, true);
 }
 
 void NLA_OT_view_all(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "View All";
-	ot->idname = "NLA_OT_view_all";
-	ot->description = "Reset viewable area to show full strips range";
+  /* identifiers */
+  ot->name = "View All";
+  ot->idname = "NLA_OT_view_all";
+  ot->description = "Reset viewable area to show full strips range";
 
-	/* api callbacks */
-	ot->exec = nlaedit_viewall_exec;
-	ot->poll = ED_operator_nla_active;
+  /* api callbacks */
+  ot->exec = nlaedit_viewall_exec;
+  ot->poll = ED_operator_nla_active;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 void NLA_OT_view_selected(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "View Selected";
-	ot->idname = "NLA_OT_view_selected";
-	ot->description = "Reset viewable area to show selected strips range";
+  /* identifiers */
+  ot->name = "View Selected";
+  ot->idname = "NLA_OT_view_selected";
+  ot->description = "Reset viewable area to show selected strips range";
 
-	/* api callbacks */
-	ot->exec = nlaedit_viewsel_exec;
-	ot->poll = ED_operator_nla_active;
+  /* api callbacks */
+  ot->exec = nlaedit_viewsel_exec;
+  ot->poll = ED_operator_nla_active;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* *********************************************** */
 
 static int nlaedit_viewframe_exec(bContext *C, wmOperator *op)
 {
-	const int smooth_viewtx = WM_operator_smooth_viewtx_get(op);
-	ANIM_center_frame(C, smooth_viewtx);
-	return OPERATOR_FINISHED;
+  const int smooth_viewtx = WM_operator_smooth_viewtx_get(op);
+  ANIM_center_frame(C, smooth_viewtx);
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_view_frame(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "View Frame";
-	ot->idname = "NLA_OT_view_frame";
-	ot->description = "Reset viewable area to show range around current frame";
+  /* identifiers */
+  ot->name = "View Frame";
+  ot->idname = "NLA_OT_view_frame";
+  ot->description = "Reset viewable area to show range around current frame";
 
-	/* api callbacks */
-	ot->exec = nlaedit_viewframe_exec;
-	ot->poll = ED_operator_nla_active;
+  /* api callbacks */
+  ot->exec = nlaedit_viewframe_exec;
+  ot->poll = ED_operator_nla_active;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* *********************************************** */
@@ -578,138 +581,144 @@ void NLA_OT_view_frame(wmOperatorType *ot)
 /* Add a new Action-Clip strip to the active track
  * (or the active block if no space in the track) */
 
-
 /* add the specified action as new strip */
 static int nlaedit_add_actionclip_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-	Scene *scene;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	size_t items;
-	int filter;
-
-	bAction *act;
-
-	float cfra;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-
-	scene = ac.scene;
-	cfra = (float)CFRA;
-
-	/* get action to use */
-	act = BLI_findlink(&CTX_data_main(C)->actions, RNA_enum_get(op->ptr, "action"));
-
-	if (act == NULL) {
-		BKE_report(op->reports, RPT_ERROR, "No valid action to add");
-		//printf("Add strip - actname = '%s'\n", actname);
-		return OPERATOR_CANCELLED;
-	}
-	else if (act->idroot == 0) {
-		/* hopefully in this case (i.e. library of userless actions),
-		 * the user knows what they're doing... */
-		BKE_reportf(op->reports, RPT_WARNING,
-		            "Action '%s' does not specify what data-blocks it can be used on "
-		            "(try setting the 'ID Root Type' setting from the data-blocks editor "
-		            "for this action to avoid future problems)",
-		            act->id.name + 2);
-	}
-
-	/* add tracks to empty but selected animdata blocks so that strips can be added to those directly
-	 * without having to manually add tracks first
-	 */
-	nlaedit_add_tracks_empty(&ac);
-
-	/* get a list of the editable tracks being shown in the NLA
-	 * - this is limited to active ones for now, but could be expanded to
-	 */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ACTIVE | ANIMFILTER_FOREDIT);
-	items = ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
-
-	if (items == 0) {
-		BKE_report(op->reports, RPT_ERROR,
-		           "No active track(s) to add strip to, select an existing track or add one before trying again");
-		return OPERATOR_CANCELLED;
-	}
-
-	/* for every active track,
-	 * try to add strip to free space in track or to the top of the stack if no space */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		AnimData *adt = ale->adt;
-		NlaStrip *strip = NULL;
-
-		/* sanity check: only apply actions of the right type for this ID
-		 * NOTE: in the case that this hasn't been set, we've already warned the user about this already
-		 */
-		if ((act->idroot) && (act->idroot != GS(ale->id->name))) {
-			BKE_reportf(op->reports, RPT_ERROR,
-			            "Could not add action '%s' as it cannot be used relative to ID-blocks of type '%s'",
-			            act->id.name + 2, ale->id->name);
-			continue;
-		}
-
-		/* create a new strip, and offset it to start on the current frame */
-		strip = BKE_nlastrip_new(act);
-
-		strip->end      += (cfra - strip->start);
-		strip->start     = cfra;
-
-		/* firstly try adding strip to our current track, but if that fails, add to a new track */
-		if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
-			/* trying to add to the current failed (no space),
-			 * so add a new track to the stack, and add to that...
-			 */
-			nlt = BKE_nlatrack_add(adt, NULL);
-			BKE_nlatrack_add_strip(nlt, strip);
-		}
-
-		/* auto-name it */
-		BKE_nlastrip_validate_name(adt, strip);
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	DEG_relations_tag_update(ac.bmain);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+  Scene *scene;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  size_t items;
+  int filter;
+
+  bAction *act;
+
+  float cfra;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+
+  scene = ac.scene;
+  cfra = (float)CFRA;
+
+  /* get action to use */
+  act = BLI_findlink(&CTX_data_main(C)->actions, RNA_enum_get(op->ptr, "action"));
+
+  if (act == NULL) {
+    BKE_report(op->reports, RPT_ERROR, "No valid action to add");
+    //printf("Add strip - actname = '%s'\n", actname);
+    return OPERATOR_CANCELLED;
+  }
+  else if (act->idroot == 0) {
+    /* hopefully in this case (i.e. library of userless actions),
+     * the user knows what they're doing... */
+    BKE_reportf(op->reports,
+                RPT_WARNING,
+                "Action '%s' does not specify what data-blocks it can be used on "
+                "(try setting the 'ID Root Type' setting from the data-blocks editor "
+                "for this action to avoid future problems)",
+                act->id.name + 2);
+  }
+
+  /* add tracks to empty but selected animdata blocks so that strips can be added to those directly
+   * without having to manually add tracks first
+   */
+  nlaedit_add_tracks_empty(&ac);
+
+  /* get a list of the editable tracks being shown in the NLA
+   * - this is limited to active ones for now, but could be expanded to
+   */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_ACTIVE | ANIMFILTER_FOREDIT);
+  items = ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+
+  if (items == 0) {
+    BKE_report(op->reports,
+               RPT_ERROR,
+               "No active track(s) to add strip to, select an existing track or add one before "
+               "trying again");
+    return OPERATOR_CANCELLED;
+  }
+
+  /* for every active track,
+   * try to add strip to free space in track or to the top of the stack if no space */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    AnimData *adt = ale->adt;
+    NlaStrip *strip = NULL;
+
+    /* sanity check: only apply actions of the right type for this ID
+     * NOTE: in the case that this hasn't been set, we've already warned the user about this already
+     */
+    if ((act->idroot) && (act->idroot != GS(ale->id->name))) {
+      BKE_reportf(
+          op->reports,
+          RPT_ERROR,
+          "Could not add action '%s' as it cannot be used relative to ID-blocks of type '%s'",
+          act->id.name + 2,
+          ale->id->name);
+      continue;
+    }
+
+    /* create a new strip, and offset it to start on the current frame */
+    strip = BKE_nlastrip_new(act);
+
+    strip->end += (cfra - strip->start);
+    strip->start = cfra;
+
+    /* firstly try adding strip to our current track, but if that fails, add to a new track */
+    if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
+      /* trying to add to the current failed (no space),
+       * so add a new track to the stack, and add to that...
+       */
+      nlt = BKE_nlatrack_add(adt, NULL);
+      BKE_nlatrack_add_strip(nlt, strip);
+    }
+
+    /* auto-name it */
+    BKE_nlastrip_validate_name(adt, strip);
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  DEG_relations_tag_update(ac.bmain);
+
+  /* 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_actionclip_add(wmOperatorType *ot)
 {
-	PropertyRNA *prop;
-
-	/* identifiers */
-	ot->name = "Add Action Strip";
-	ot->idname = "NLA_OT_actionclip_add";
-	ot->description = "Add an Action-Clip strip (i.e. an NLA Strip referencing an Action) to the active track";
-
-	/* api callbacks */
-	ot->invoke = WM_enum_search_invoke;
-	ot->exec = nlaedit_add_actionclip_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* props */
-	// TODO: this would be nicer as an ID-pointer...
-	prop = RNA_def_enum(ot->srna, "action", DummyRNA_NULL_items, 0, "Action", "");
-	RNA_def_enum_funcs(prop, RNA_action_itemf);
-	RNA_def_property_flag(prop, PROP_ENUM_NO_TRANSLATE);
-	ot->prop = prop;
+  PropertyRNA *prop;
+
+  /* identifiers */
+  ot->name = "Add Action Strip";
+  ot->idname = "NLA_OT_actionclip_add";
+  ot->description =
+      "Add an Action-Clip strip (i.e. an NLA Strip referencing an Action) to the active track";
+
+  /* api callbacks */
+  ot->invoke = WM_enum_search_invoke;
+  ot->exec = nlaedit_add_actionclip_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* props */
+  // TODO: this would be nicer as an ID-pointer...
+  prop = RNA_def_enum(ot->srna, "action", DummyRNA_NULL_items, 0, "Action", "");
+  RNA_def_enum_funcs(prop, RNA_action_itemf);
+  RNA_def_property_flag(prop, PROP_ENUM_NO_TRANSLATE);
+  ot->prop = prop;
 }
 
 /* ******************** Add Transition Operator ***************************** */
@@ -717,117 +726,119 @@ void NLA_OT_actionclip_add(wmOperatorType *ot)
 
 static int nlaedit_add_transition_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	bool done = false;
-
-	/* 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);
-
-	/* for each track, find pairs of strips to add transitions to */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		AnimData *adt = ale->adt;
-		NlaStrip *s1, *s2;
-
-		/* get initial pair of strips */
-		if (ELEM(nlt->strips.first, NULL, nlt->strips.last))
-			continue;
-		s1 = nlt->strips.first;
-		s2 = s1->next;
-
-		/* loop over strips */
-		for (; s1 && s2; s1 = s2, s2 = s2->next) {
-			NlaStrip *strip;
-
-			/* check if both are selected */
-			if (ELEM(0, (s1->flag & NLASTRIP_FLAG_SELECT), (s2->flag & NLASTRIP_FLAG_SELECT)))
-				continue;
-			/* check if there's space between the two */
-			if (IS_EQF(s1->end, s2->start))
-				continue;
-			/* make sure neither one is a transition
-			 * - although this is impossible to create with the standard tools,
-			 *   the user may have altered the settings
-			 */
-			if (ELEM(NLASTRIP_TYPE_TRANSITION, s1->type, s2->type))
-				continue;
-			/* also make sure neither one is a soundclip */
-			if (ELEM(NLASTRIP_TYPE_SOUND, s1->type, s2->type))
-				continue;
-
-			/* allocate new strip */
-			strip = MEM_callocN(sizeof(NlaStrip), "NlaStrip");
-			BLI_insertlinkafter(&nlt->strips, s1, strip);
-
-			/* set the type */
-			strip->type = NLASTRIP_TYPE_TRANSITION;
-
-			/* generic settings
-			 * - selected flag to highlight this to the user
-			 * - auto-blends to ensure that blend in/out values are automatically
-			 *   determined by overlaps of strips
-			 */
-			strip->flag = NLASTRIP_FLAG_SELECT | NLASTRIP_FLAG_AUTO_BLENDS;
-
-			/* range is simply defined as the endpoints of the adjacent strips */
-			strip->start = s1->end;
-			strip->end   = s2->start;
-
-			/* scale and repeat aren't of any use, but shouldn't ever be 0 */
-			strip->scale = 1.0f;
-			strip->repeat = 1.0f;
-
-			/* auto-name it */
-			BKE_nlastrip_validate_name(adt, strip);
-
-			/* make note of this */
-			done = true;
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* was anything added? */
-	if (done) {
-		/* refresh auto strip properties */
-		ED_nla_postop_refresh(&ac);
-
-		/* set notifier that things have changed */
-		WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-		/* done */
-		return OPERATOR_FINISHED;
-	}
-	else {
-		BKE_report(op->reports, RPT_ERROR, "Needs at least a pair of adjacent selected strips with a gap between them");
-		return OPERATOR_CANCELLED;
-	}
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  bool done = false;
+
+  /* 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);
+
+  /* for each track, find pairs of strips to add transitions to */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    AnimData *adt = ale->adt;
+    NlaStrip *s1, *s2;
+
+    /* get initial pair of strips */
+    if (ELEM(nlt->strips.first, NULL, nlt->strips.last))
+      continue;
+    s1 = nlt->strips.first;
+    s2 = s1->next;
+
+    /* loop over strips */
+    for (; s1 && s2; s1 = s2, s2 = s2->next) {
+      NlaStrip *strip;
+
+      /* check if both are selected */
+      if (ELEM(0, (s1->flag & NLASTRIP_FLAG_SELECT), (s2->flag & NLASTRIP_FLAG_SELECT)))
+        continue;
+      /* check if there's space between the two */
+      if (IS_EQF(s1->end, s2->start))
+        continue;
+      /* make sure neither one is a transition
+       * - although this is impossible to create with the standard tools,
+       *   the user may have altered the settings
+       */
+      if (ELEM(NLASTRIP_TYPE_TRANSITION, s1->type, s2->type))
+        continue;
+      /* also make sure neither one is a soundclip */
+      if (ELEM(NLASTRIP_TYPE_SOUND, s1->type, s2->type))
+        continue;
+
+      /* allocate new strip */
+      strip = MEM_callocN(sizeof(NlaStrip), "NlaStrip");
+      BLI_insertlinkafter(&nlt->strips, s1, strip);
+
+      /* set the type */
+      strip->type = NLASTRIP_TYPE_TRANSITION;
+
+      /* generic settings
+       * - selected flag to highlight this to the user
+       * - auto-blends to ensure that blend in/out values are automatically
+       *   determined by overlaps of strips
+       */
+      strip->flag = NLASTRIP_FLAG_SELECT | NLASTRIP_FLAG_AUTO_BLENDS;
+
+      /* range is simply defined as the endpoints of the adjacent strips */
+      strip->start = s1->end;
+      strip->end = s2->start;
+
+      /* scale and repeat aren't of any use, but shouldn't ever be 0 */
+      strip->scale = 1.0f;
+      strip->repeat = 1.0f;
+
+      /* auto-name it */
+      BKE_nlastrip_validate_name(adt, strip);
+
+      /* make note of this */
+      done = true;
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* was anything added? */
+  if (done) {
+    /* refresh auto strip properties */
+    ED_nla_postop_refresh(&ac);
+
+    /* set notifier that things have changed */
+    WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+
+    /* done */
+    return OPERATOR_FINISHED;
+  }
+  else {
+    BKE_report(op->reports,
+               RPT_ERROR,
+               "Needs at least a pair of adjacent selected strips with a gap between them");
+    return OPERATOR_CANCELLED;
+  }
 }
 
 void NLA_OT_transition_add(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Add Transition";
-	ot->idname = "NLA_OT_transition_add";
-	ot->description = "Add a transition strip between two adjacent selected strips";
+  /* identifiers */
+  ot->name = "Add Transition";
+  ot->idname = "NLA_OT_transition_add";
+  ot->description = "Add a transition strip between two adjacent selected strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_add_transition_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_add_transition_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Add Sound Clip Operator ***************************** */
@@ -835,84 +846,85 @@ void NLA_OT_transition_add(wmOperatorType *ot)
 
 static int nlaedit_add_sound_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
 
-	Scene *scene;
-	int cfra;
+  Scene *scene;
+  int cfra;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
 
-	scene = ac.scene;
-	cfra = CFRA;
+  scene = ac.scene;
+  cfra = CFRA;
 
-	/* get a list of the editable tracks being shown in the NLA */
-	filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_SEL | ANIMFILTER_FOREDIT);
-	ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+  /* get a list of the editable tracks being shown in the NLA */
+  filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_SEL |
+            ANIMFILTER_FOREDIT);
+  ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
 
-	/* for each track, add sound clips if it belongs to a speaker */
-	// TODO: what happens if there aren't any tracks... well that's a more general problem for later
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		Object *ob = (Object *)ale->id; /* may not be object until we actually check! */
+  /* for each track, add sound clips if it belongs to a speaker */
+  // TODO: what happens if there aren't any tracks... well that's a more general problem for later
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    Object *ob = (Object *)ale->id; /* may not be object until we actually check! */
 
-		AnimData *adt = ale->adt;
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
+    AnimData *adt = ale->adt;
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
 
-		/* does this belong to speaker - assumed to live on Object level only */
-		if ((GS(ale->id->name) != ID_OB) || (ob->type != OB_SPEAKER))
-			continue;
+    /* does this belong to speaker - assumed to live on Object level only */
+    if ((GS(ale->id->name) != ID_OB) || (ob->type != OB_SPEAKER))
+      continue;
 
-		/* create a new strip, and offset it to start on the current frame */
-		strip = BKE_nla_add_soundstrip(ac.scene, ob->data);
+    /* create a new strip, and offset it to start on the current frame */
+    strip = BKE_nla_add_soundstrip(ac.scene, ob->data);
 
-		strip->start += cfra;
-		strip->end   += cfra;
+    strip->start += cfra;
+    strip->end += cfra;
 
-		/* firstly try adding strip to our current track, but if that fails, add to a new track */
-		if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
-			/* trying to add to the current failed (no space),
-			 * so add a new track to the stack, and add to that...
-			 */
-			nlt = BKE_nlatrack_add(adt, NULL);
-			BKE_nlatrack_add_strip(nlt, strip);
-		}
+    /* firstly try adding strip to our current track, but if that fails, add to a new track */
+    if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
+      /* trying to add to the current failed (no space),
+       * so add a new track to the stack, and add to that...
+       */
+      nlt = BKE_nlatrack_add(adt, NULL);
+      BKE_nlatrack_add_strip(nlt, strip);
+    }
 
-		/* auto-name it */
-		BKE_nlastrip_validate_name(adt, strip);
-	}
+    /* auto-name it */
+    BKE_nlastrip_validate_name(adt, strip);
+  }
 
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
 
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
 
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+  /* set notifier that things have changed */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
 
-	/* done */
-	return OPERATOR_FINISHED;
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_soundclip_add(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Add Sound Clip";
-	ot->idname = "NLA_OT_soundclip_add";
-	ot->description = "Add a strip for controlling when speaker plays its sound clip";
+  /* identifiers */
+  ot->name = "Add Sound Clip";
+  ot->idname = "NLA_OT_soundclip_add";
+  ot->description = "Add a strip for controlling when speaker plays its sound clip";
 
-	/* api callbacks */
-	ot->exec = nlaedit_add_sound_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_add_sound_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Add Meta-Strip Operator ***************************** */
@@ -921,63 +933,63 @@ void NLA_OT_soundclip_add(wmOperatorType *ot)
 /* add the specified action as new strip */
 static int nlaedit_add_meta_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* 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);
+  /* 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);
 
-	/* for each track, find pairs of strips to add transitions to */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		AnimData *adt = ale->adt;
-		NlaStrip *strip;
+  /* for each track, find pairs of strips to add transitions to */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    AnimData *adt = ale->adt;
+    NlaStrip *strip;
 
-		/* create meta-strips from the continuous chains of selected strips */
-		BKE_nlastrips_make_metas(&nlt->strips, 0);
+    /* create meta-strips from the continuous chains of selected strips */
+    BKE_nlastrips_make_metas(&nlt->strips, 0);
 
-		/* name the metas */
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* auto-name this strip if selected (that means it is a meta) */
-			if (strip->flag & NLASTRIP_FLAG_SELECT)
-				BKE_nlastrip_validate_name(adt, strip);
-		}
+    /* name the metas */
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* auto-name this strip if selected (that means it is a meta) */
+      if (strip->flag & NLASTRIP_FLAG_SELECT)
+        BKE_nlastrip_validate_name(adt, strip);
+    }
 
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
 
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
 
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+  /* set notifier that things have changed */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
 
-	/* done */
-	return OPERATOR_FINISHED;
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_meta_add(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Add Meta-Strips";
-	ot->idname = "NLA_OT_meta_add";
-	ot->description = "Add new meta-strips incorporating the selected strips";
+  /* identifiers */
+  ot->name = "Add Meta-Strips";
+  ot->idname = "NLA_OT_meta_add";
+  ot->description = "Add new meta-strips incorporating the selected strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_add_meta_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_add_meta_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Remove Meta-Strip Operator ***************************** */
@@ -985,54 +997,54 @@ void NLA_OT_meta_add(wmOperatorType *ot)
 
 static int nlaedit_remove_meta_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* 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);
+  /* 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);
 
-	/* for each track, find pairs of strips to add transitions to */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
+  /* for each track, find pairs of strips to add transitions to */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
 
-		/* clear all selected meta-strips, regardless of whether they are temporary or not */
-		BKE_nlastrips_clear_metas(&nlt->strips, 1, 0);
+    /* clear all selected meta-strips, regardless of whether they are temporary or not */
+    BKE_nlastrips_clear_metas(&nlt->strips, 1, 0);
 
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
 
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
 
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+  /* set notifier that things have changed */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
 
-	/* done */
-	return OPERATOR_FINISHED;
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_meta_remove(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Remove Meta-Strips";
-	ot->idname = "NLA_OT_meta_remove";
-	ot->description = "Separate out the strips held by the selected meta-strips";
+  /* identifiers */
+  ot->name = "Remove Meta-Strips";
+  ot->idname = "NLA_OT_meta_remove";
+  ot->description = "Separate out the strips held by the selected meta-strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_remove_meta_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_remove_meta_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Duplicate Strips Operator ************************** */
@@ -1042,113 +1054,118 @@ void NLA_OT_meta_remove(wmOperatorType *ot)
 
 static int nlaedit_duplicate_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	bool linked = RNA_boolean_get(op->ptr, "linked");
-	bool done = false;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-
-	/* get a list of 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);
-
-	/* duplicate strips in tracks starting from the last one so that we're
-	 * less likely to duplicate strips we just duplicated...
-	 */
-	for (ale = anim_data.last; ale; ale = ale->prev) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		AnimData *adt = ale->adt;
-		NlaStrip *strip, *nstrip, *next;
-		NlaTrack *track;
-
-		for (strip = nlt->strips.first; strip; strip = next) {
-			next = strip->next;
-
-			/* if selected, split the strip at its midpoint */
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* make a copy (assume that this is possible) */
-				nstrip = BKE_nlastrip_copy(ac.bmain, strip, linked, 0);
-
-				/* in case there's no space in the track above,
-				 * or we haven't got a reference to it yet, try adding */
-				if (BKE_nlatrack_add_strip(nlt->next, nstrip) == 0) {
-					/* need to add a new track above the one above the current one
-					 * - if the current one is the last one, nlt->next will be NULL, which defaults to adding
-					 *   at the top of the stack anyway...
-					 */
-					track = BKE_nlatrack_add(adt, nlt->next);
-					BKE_nlatrack_add_strip(track, nstrip);
-				}
-
-				/* deselect the original and the active flag */
-				strip->flag &= ~(NLASTRIP_FLAG_SELECT | NLASTRIP_FLAG_ACTIVE);
-
-				/* auto-name newly created strip */
-				BKE_nlastrip_validate_name(adt, nstrip);
-
-				done = true;
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	if (done) {
-		/* refresh auto strip properties */
-		ED_nla_postop_refresh(&ac);
-
-		if (!linked) {
-			DEG_relations_tag_update(ac.bmain);
-		}
-
-		/* set notifier that things have changed */
-		WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-		/* done */
-		return OPERATOR_FINISHED;
-	}
-	else
-		return OPERATOR_CANCELLED;
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  bool linked = RNA_boolean_get(op->ptr, "linked");
+  bool done = false;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+
+  /* get a list of 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);
+
+  /* duplicate strips in tracks starting from the last one so that we're
+   * less likely to duplicate strips we just duplicated...
+   */
+  for (ale = anim_data.last; ale; ale = ale->prev) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    AnimData *adt = ale->adt;
+    NlaStrip *strip, *nstrip, *next;
+    NlaTrack *track;
+
+    for (strip = nlt->strips.first; strip; strip = next) {
+      next = strip->next;
+
+      /* if selected, split the strip at its midpoint */
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* make a copy (assume that this is possible) */
+        nstrip = BKE_nlastrip_copy(ac.bmain, strip, linked, 0);
+
+        /* in case there's no space in the track above,
+         * or we haven't got a reference to it yet, try adding */
+        if (BKE_nlatrack_add_strip(nlt->next, nstrip) == 0) {
+          /* need to add a new track above the one above the current one
+           * - if the current one is the last one, nlt->next will be NULL, which defaults to adding
+           *   at the top of the stack anyway...
+           */
+          track = BKE_nlatrack_add(adt, nlt->next);
+          BKE_nlatrack_add_strip(track, nstrip);
+        }
+
+        /* deselect the original and the active flag */
+        strip->flag &= ~(NLASTRIP_FLAG_SELECT | NLASTRIP_FLAG_ACTIVE);
+
+        /* auto-name newly created strip */
+        BKE_nlastrip_validate_name(adt, nstrip);
+
+        done = true;
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  if (done) {
+    /* refresh auto strip properties */
+    ED_nla_postop_refresh(&ac);
+
+    if (!linked) {
+      DEG_relations_tag_update(ac.bmain);
+    }
+
+    /* set notifier that things have changed */
+    WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+
+    /* done */
+    return OPERATOR_FINISHED;
+  }
+  else
+    return OPERATOR_CANCELLED;
 }
 
 static int nlaedit_duplicate_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
 {
-	nlaedit_duplicate_exec(C, op);
+  nlaedit_duplicate_exec(C, op);
 
-	RNA_enum_set(op->ptr, "mode", TFM_TRANSLATION);
-	WM_operator_name_call(C, "TRANSFORM_OT_transform", WM_OP_INVOKE_REGION_WIN, op->ptr);
+  RNA_enum_set(op->ptr, "mode", TFM_TRANSLATION);
+  WM_operator_name_call(C, "TRANSFORM_OT_transform", WM_OP_INVOKE_REGION_WIN, op->ptr);
 
-	return OPERATOR_FINISHED;
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_duplicate(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Duplicate Strips";
-	ot->idname = "NLA_OT_duplicate";
-	ot->description = "Duplicate selected NLA-Strips, adding the new strips in new tracks above the originals";
-
-	/* api callbacks */
-	ot->invoke = nlaedit_duplicate_invoke;
-	ot->exec = nlaedit_duplicate_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* own properties */
-	ot->prop = RNA_def_boolean(ot->srna, "linked", false, "Linked", "When duplicating strips, assign new copies of the actions they use");
-
-	/* to give to transform */
-	RNA_def_enum(ot->srna, "mode", rna_enum_transform_mode_types, TFM_TRANSLATION, "Mode", "");
+  /* identifiers */
+  ot->name = "Duplicate Strips";
+  ot->idname = "NLA_OT_duplicate";
+  ot->description =
+      "Duplicate selected NLA-Strips, adding the new strips in new tracks above the originals";
+
+  /* api callbacks */
+  ot->invoke = nlaedit_duplicate_invoke;
+  ot->exec = nlaedit_duplicate_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* own properties */
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "linked",
+                             false,
+                             "Linked",
+                             "When duplicating strips, assign new copies of the actions they use");
+
+  /* to give to transform */
+  RNA_def_enum(ot->srna, "mode", rna_enum_transform_mode_types, TFM_TRANSLATION, "Mode", "");
 }
 
 /* ******************** Delete Strips Operator ***************************** */
@@ -1156,72 +1173,72 @@ void NLA_OT_duplicate(wmOperatorType *ot)
 
 static int nlaedit_delete_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* 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);
+  /* 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);
 
-	/* for each NLA-Track, delete all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip, *nstrip;
+  /* for each NLA-Track, delete all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip, *nstrip;
 
-		for (strip = nlt->strips.first; strip; strip = nstrip) {
-			nstrip = strip->next;
+    for (strip = nlt->strips.first; strip; strip = nstrip) {
+      nstrip = strip->next;
 
-			/* if selected, delete */
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* if a strip either side of this was a transition, delete those too */
-				if ((strip->prev) && (strip->prev->type == NLASTRIP_TYPE_TRANSITION))
-					BKE_nlastrip_free(&nlt->strips, strip->prev, true);
-				if ((nstrip) && (nstrip->type == NLASTRIP_TYPE_TRANSITION)) {
-					nstrip = nstrip->next;
-					BKE_nlastrip_free(&nlt->strips, strip->next, true);
-				}
+      /* if selected, delete */
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* if a strip either side of this was a transition, delete those too */
+        if ((strip->prev) && (strip->prev->type == NLASTRIP_TYPE_TRANSITION))
+          BKE_nlastrip_free(&nlt->strips, strip->prev, true);
+        if ((nstrip) && (nstrip->type == NLASTRIP_TYPE_TRANSITION)) {
+          nstrip = nstrip->next;
+          BKE_nlastrip_free(&nlt->strips, strip->next, true);
+        }
 
-				/* finally, delete this strip */
-				BKE_nlastrip_free(&nlt->strips, strip, true);
-			}
-		}
-	}
+        /* finally, delete this strip */
+        BKE_nlastrip_free(&nlt->strips, strip, true);
+      }
+    }
+  }
 
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
 
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
 
-	DEG_relations_tag_update(ac.bmain);
+  DEG_relations_tag_update(ac.bmain);
 
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+  /* set notifier that things have changed */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
 
-	/* done */
-	return OPERATOR_FINISHED;
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_delete(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Delete Strips";
-	ot->idname = "NLA_OT_delete";
-	ot->description = "Delete selected strips";
+  /* identifiers */
+  ot->name = "Delete Strips";
+  ot->idname = "NLA_OT_delete";
+  ot->description = "Delete selected strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_delete_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_delete_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Split Strips Operator ***************************** */
@@ -1231,142 +1248,143 @@ void NLA_OT_delete(wmOperatorType *ot)
 //  - variable-length splits?
 
 /* split a given Action-Clip strip */
-static void nlaedit_split_strip_actclip(Main *bmain, AnimData *adt, NlaTrack *nlt, NlaStrip *strip, float cfra)
+static void nlaedit_split_strip_actclip(
+    Main *bmain, AnimData *adt, NlaTrack *nlt, NlaStrip *strip, float cfra)
 {
-	NlaStrip *nstrip;
-	float splitframe, splitaframe;
-
-	/* calculate the frames to do the splitting at
-	 * - use current frame if within extents of strip
-	 */
-	if ((cfra > strip->start) && (cfra < strip->end)) {
-		/* use the current frame */
-		splitframe = cfra;
-		splitaframe = nlastrip_get_frame(strip, cfra, NLATIME_CONVERT_UNMAP);
-	}
-	else {
-		/* split in the middle */
-		float len;
-
-		/* strip extents */
-		len = strip->end - strip->start;
-		if (IS_EQF(len, 0.0f))
-			return;
-		else
-			splitframe = strip->start + (len / 2.0f);
-
-		/* action range */
-		len = strip->actend - strip->actstart;
-		if (IS_EQF(len, 0.0f))
-			splitaframe = strip->actend;
-		else
-			splitaframe = strip->actstart + (len / 2.0f);
-	}
-
-	/* make a copy (assume that this is possible) and append
-	 * it immediately after the current strip
-	 */
-	nstrip = BKE_nlastrip_copy(bmain, strip, true, 0);
-	BLI_insertlinkafter(&nlt->strips, strip, nstrip);
-
-	/* Set the endpoint of the first strip and the start of the new strip
-	 * to the split-frame values calculated above.
-	 */
-	strip->end = splitframe;
-	nstrip->start = splitframe;
-
-	if ((splitaframe > strip->actstart) && (splitaframe < strip->actend)) {
-		/* only do this if we're splitting down the middle...  */
-		strip->actend = splitaframe;
-		nstrip->actstart = splitaframe;
-	}
-
-	/* clear the active flag from the copy */
-	nstrip->flag &= ~NLASTRIP_FLAG_ACTIVE;
-
-	/* auto-name the new strip */
-	BKE_nlastrip_validate_name(adt, nstrip);
+  NlaStrip *nstrip;
+  float splitframe, splitaframe;
+
+  /* calculate the frames to do the splitting at
+   * - use current frame if within extents of strip
+   */
+  if ((cfra > strip->start) && (cfra < strip->end)) {
+    /* use the current frame */
+    splitframe = cfra;
+    splitaframe = nlastrip_get_frame(strip, cfra, NLATIME_CONVERT_UNMAP);
+  }
+  else {
+    /* split in the middle */
+    float len;
+
+    /* strip extents */
+    len = strip->end - strip->start;
+    if (IS_EQF(len, 0.0f))
+      return;
+    else
+      splitframe = strip->start + (len / 2.0f);
+
+    /* action range */
+    len = strip->actend - strip->actstart;
+    if (IS_EQF(len, 0.0f))
+      splitaframe = strip->actend;
+    else
+      splitaframe = strip->actstart + (len / 2.0f);
+  }
+
+  /* make a copy (assume that this is possible) and append
+   * it immediately after the current strip
+   */
+  nstrip = BKE_nlastrip_copy(bmain, strip, true, 0);
+  BLI_insertlinkafter(&nlt->strips, strip, nstrip);
+
+  /* Set the endpoint of the first strip and the start of the new strip
+   * to the split-frame values calculated above.
+   */
+  strip->end = splitframe;
+  nstrip->start = splitframe;
+
+  if ((splitaframe > strip->actstart) && (splitaframe < strip->actend)) {
+    /* only do this if we're splitting down the middle...  */
+    strip->actend = splitaframe;
+    nstrip->actstart = splitaframe;
+  }
+
+  /* clear the active flag from the copy */
+  nstrip->flag &= ~NLASTRIP_FLAG_ACTIVE;
+
+  /* auto-name the new strip */
+  BKE_nlastrip_validate_name(adt, nstrip);
 }
 
 /* split a given Meta strip */
 static void nlaedit_split_strip_meta(NlaTrack *nlt, NlaStrip *strip)
 {
-	/* simply ungroup it for now...  */
-	BKE_nlastrips_clear_metastrip(&nlt->strips, strip);
+  /* simply ungroup it for now...  */
+  BKE_nlastrips_clear_metastrip(&nlt->strips, strip);
 }
 
 /* ----- */
 
 static int nlaedit_split_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 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);
-
-	/* for each NLA-Track, split all selected strips into two strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		AnimData *adt = ale->adt;
-		NlaStrip *strip, *next;
-
-		for (strip = nlt->strips.first; strip; strip = next) {
-			next = strip->next;
-
-			/* if selected, split the strip at its midpoint */
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* splitting method depends on the type of strip */
-				switch (strip->type) {
-					case NLASTRIP_TYPE_CLIP: /* action-clip */
-						nlaedit_split_strip_actclip(ac.bmain, adt, nlt, strip, (float)ac.scene->r.cfra);
-						break;
-
-					case NLASTRIP_TYPE_META: /* meta-strips need special handling */
-						nlaedit_split_strip_meta(nlt, strip);
-						break;
-
-					default: /* for things like Transitions, do not split! */
-						break;
-				}
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  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 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);
+
+  /* for each NLA-Track, split all selected strips into two strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    AnimData *adt = ale->adt;
+    NlaStrip *strip, *next;
+
+    for (strip = nlt->strips.first; strip; strip = next) {
+      next = strip->next;
+
+      /* if selected, split the strip at its midpoint */
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* splitting method depends on the type of strip */
+        switch (strip->type) {
+          case NLASTRIP_TYPE_CLIP: /* action-clip */
+            nlaedit_split_strip_actclip(ac.bmain, adt, nlt, strip, (float)ac.scene->r.cfra);
+            break;
+
+          case NLASTRIP_TYPE_META: /* meta-strips need special handling */
+            nlaedit_split_strip_meta(nlt, strip);
+            break;
+
+          default: /* for things like Transitions, do not split! */
+            break;
+        }
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  /* 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_split(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Split Strips";
-	ot->idname = "NLA_OT_split";
-	ot->description = "Split selected strips at their midpoints";
+  /* identifiers */
+  ot->name = "Split Strips";
+  ot->idname = "NLA_OT_split";
+  ot->description = "Split selected strips at their midpoints";
 
-	/* api callbacks */
-	ot->exec = nlaedit_split_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_split_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* *********************************************** */
@@ -1377,62 +1395,62 @@ void NLA_OT_split(wmOperatorType *ot)
 
 static int nlaedit_toggle_mute_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);
-
-	/* go over all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		/* for every selected strip, toggle muting  */
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* just flip the mute flag for now */
-				// TODO: have a pre-pass to check if mute all or unmute all?
-				strip->flag ^= NLASTRIP_FLAG_MUTED;
-
-				/* tag AnimData to get recalculated */
-				ale->update |= ANIM_UPDATE_DEPS;
-			}
-		}
-	}
-
-	/* cleanup */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  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);
+
+  /* go over all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    /* for every selected strip, toggle muting  */
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* just flip the mute flag for now */
+        // TODO: have a pre-pass to check if mute all or unmute all?
+        strip->flag ^= NLASTRIP_FLAG_MUTED;
+
+        /* tag AnimData to get recalculated */
+        ale->update |= ANIM_UPDATE_DEPS;
+      }
+    }
+  }
+
+  /* cleanup */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&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_mute_toggle(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Toggle Muting";
-	ot->idname = "NLA_OT_mute_toggle";
-	ot->description = "Mute or un-mute selected strips";
+  /* identifiers */
+  ot->name = "Toggle Muting";
+  ot->idname = "NLA_OT_mute_toggle";
+  ot->description = "Mute or un-mute selected strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_toggle_mute_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_toggle_mute_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Swap Strips Operator ************************** */
@@ -1440,160 +1458,167 @@ void NLA_OT_mute_toggle(wmOperatorType *ot)
 
 static int nlaedit_swap_exec(bContext *C, wmOperator *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);
-
-	/* consider each track in turn */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-
-		NlaStrip *strip, *stripN = NULL;
-		NlaStrip *sa = NULL, *sb = NULL;
-
-		/* make temporary metastrips so that entire islands of selections can be moved around */
-		BKE_nlastrips_make_metas(&nlt->strips, 1);
-
-		/* special case: if there is only 1 island (i.e. temp meta BUT NOT unselected/normal/normal-meta strips) left after this,
-		 * and this island has two strips inside it, then we should be able to just swap these still...
-		 */
-		if (BLI_listbase_is_empty(&nlt->strips) == false) {
-			NlaStrip *mstrip = (NlaStrip *)nlt->strips.first;
-
-			if ((mstrip->flag & NLASTRIP_FLAG_TEMP_META) &&
-			    (BLI_listbase_count_at_most(&mstrip->strips, 3) == 2))
-			{
-				/* remove this temp meta, so that we can see the strips inside */
-				BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
-			}
-		}
-
-		/* get two selected strips only (these will be metas due to prev step) to operate on
-		 * - only allow swapping 2, as with more the context becomes unclear
-		 */
-		for (strip = nlt->strips.first; strip; strip = stripN) {
-			stripN = strip->next;
-
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* first or second strip? */
-				if (sa == NULL) {
-					/* store as first */
-					sa = strip;
-				}
-				else if (sb == NULL) {
-					/* store as second */
-					sb = strip;
-				}
-				else {
-					/* too many selected */
-					break;
-				}
-			}
-		}
-
-		if (strip) {
-			/* too many selected warning */
-			BKE_reportf(op->reports, RPT_WARNING,
-			            "Too many clusters of strips selected in NLA Track (%s): needs exactly 2 to be selected",
-			            nlt->name);
-		}
-		else if (sa == NULL) {
-			/* no warning as this is just a common case,
-			 * and it may get annoying when doing multiple tracks */
-		}
-		else if (sb == NULL) {
-			/* too few selected warning */
-			BKE_reportf(op->reports, RPT_WARNING,
-			            "Too few clusters of strips selected in NLA Track (%s): needs exactly 2 to be selected",
-			            nlt->name);
-		}
-		else {
-			float nsa[2], nsb[2];
-
-			/* remove these strips from the track,
-			 * so that we can test if they can fit in the proposed places */
-			BLI_remlink(&nlt->strips, sa);
-			BLI_remlink(&nlt->strips, sb);
-
-			/* calculate new extents for strips */
-			/* a --> b */
-			nsa[0] = sb->start;
-			nsa[1] = sb->start + (sa->end - sa->start);
-			/* b --> a */
-			nsb[0] = sa->start;
-			nsb[1] = sa->start + (sb->end - sb->start);
-
-			/* check if the track has room for the strips to be swapped */
-			if (BKE_nlastrips_has_space(&nlt->strips, nsa[0], nsa[1]) &&
-			    BKE_nlastrips_has_space(&nlt->strips, nsb[0], nsb[1]))
-			{
-				/* set new extents for strips then */
-				sa->start = nsa[0];
-				sa->end   = nsa[1];
-				BKE_nlameta_flush_transforms(sa);
-
-				sb->start = nsb[0];
-				sb->end   = nsb[1];
-				BKE_nlameta_flush_transforms(sb);
-			}
-			else {
-				/* not enough room to swap, so show message */
-				if ((sa->flag & NLASTRIP_FLAG_TEMP_META) || (sb->flag & NLASTRIP_FLAG_TEMP_META)) {
-					BKE_report(op->reports, RPT_WARNING,
-					           "Cannot swap selected strips as they will not be able to fit in their new places");
-				}
-				else {
-					BKE_reportf(op->reports, RPT_WARNING,
-					            "Cannot swap '%s' and '%s' as one or both will not be able to fit in their new places",
-					            sa->name, sb->name);
-				}
-			}
-
-			/* add strips back to track now */
-			BKE_nlatrack_add_strip(nlt, sa);
-			BKE_nlatrack_add_strip(nlt, sb);
-		}
-
-		/* clear (temp) metastrips */
-		BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  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);
+
+  /* consider each track in turn */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+
+    NlaStrip *strip, *stripN = NULL;
+    NlaStrip *sa = NULL, *sb = NULL;
+
+    /* make temporary metastrips so that entire islands of selections can be moved around */
+    BKE_nlastrips_make_metas(&nlt->strips, 1);
+
+    /* special case: if there is only 1 island (i.e. temp meta BUT NOT unselected/normal/normal-meta strips) left after this,
+     * and this island has two strips inside it, then we should be able to just swap these still...
+     */
+    if (BLI_listbase_is_empty(&nlt->strips) == false) {
+      NlaStrip *mstrip = (NlaStrip *)nlt->strips.first;
+
+      if ((mstrip->flag & NLASTRIP_FLAG_TEMP_META) &&
+          (BLI_listbase_count_at_most(&mstrip->strips, 3) == 2)) {
+        /* remove this temp meta, so that we can see the strips inside */
+        BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
+      }
+    }
+
+    /* get two selected strips only (these will be metas due to prev step) to operate on
+     * - only allow swapping 2, as with more the context becomes unclear
+     */
+    for (strip = nlt->strips.first; strip; strip = stripN) {
+      stripN = strip->next;
+
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* first or second strip? */
+        if (sa == NULL) {
+          /* store as first */
+          sa = strip;
+        }
+        else if (sb == NULL) {
+          /* store as second */
+          sb = strip;
+        }
+        else {
+          /* too many selected */
+          break;
+        }
+      }
+    }
+
+    if (strip) {
+      /* too many selected warning */
+      BKE_reportf(
+          op->reports,
+          RPT_WARNING,
+          "Too many clusters of strips selected in NLA Track (%s): needs exactly 2 to be selected",
+          nlt->name);
+    }
+    else if (sa == NULL) {
+      /* no warning as this is just a common case,
+       * and it may get annoying when doing multiple tracks */
+    }
+    else if (sb == NULL) {
+      /* too few selected warning */
+      BKE_reportf(
+          op->reports,
+          RPT_WARNING,
+          "Too few clusters of strips selected in NLA Track (%s): needs exactly 2 to be selected",
+          nlt->name);
+    }
+    else {
+      float nsa[2], nsb[2];
+
+      /* remove these strips from the track,
+       * so that we can test if they can fit in the proposed places */
+      BLI_remlink(&nlt->strips, sa);
+      BLI_remlink(&nlt->strips, sb);
+
+      /* calculate new extents for strips */
+      /* a --> b */
+      nsa[0] = sb->start;
+      nsa[1] = sb->start + (sa->end - sa->start);
+      /* b --> a */
+      nsb[0] = sa->start;
+      nsb[1] = sa->start + (sb->end - sb->start);
+
+      /* check if the track has room for the strips to be swapped */
+      if (BKE_nlastrips_has_space(&nlt->strips, nsa[0], nsa[1]) &&
+          BKE_nlastrips_has_space(&nlt->strips, nsb[0], nsb[1])) {
+        /* set new extents for strips then */
+        sa->start = nsa[0];
+        sa->end = nsa[1];
+        BKE_nlameta_flush_transforms(sa);
+
+        sb->start = nsb[0];
+        sb->end = nsb[1];
+        BKE_nlameta_flush_transforms(sb);
+      }
+      else {
+        /* not enough room to swap, so show message */
+        if ((sa->flag & NLASTRIP_FLAG_TEMP_META) || (sb->flag & NLASTRIP_FLAG_TEMP_META)) {
+          BKE_report(
+              op->reports,
+              RPT_WARNING,
+              "Cannot swap selected strips as they will not be able to fit in their new places");
+        }
+        else {
+          BKE_reportf(op->reports,
+                      RPT_WARNING,
+                      "Cannot swap '%s' and '%s' as one or both will not be able to fit in their "
+                      "new places",
+                      sa->name,
+                      sb->name);
+        }
+      }
+
+      /* add strips back to track now */
+      BKE_nlatrack_add_strip(nlt, sa);
+      BKE_nlatrack_add_strip(nlt, sb);
+    }
+
+    /* clear (temp) metastrips */
+    BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  /* 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_swap(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Swap Strips";
-	ot->idname = "NLA_OT_swap";
-	ot->description = "Swap order of selected strips within tracks";
+  /* identifiers */
+  ot->name = "Swap Strips";
+  ot->idname = "NLA_OT_swap";
+  ot->description = "Swap order of selected strips within tracks";
 
-	/* api callbacks */
-	ot->exec = nlaedit_swap_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_swap_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Move Strips Up Operator ************************** */
@@ -1601,74 +1626,74 @@ void NLA_OT_swap(wmOperatorType *ot)
 
 static int nlaedit_move_up_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);
-
-	/* since we're potentially moving strips from lower tracks to higher tracks, we should
-	 * loop over the tracks in reverse order to avoid moving earlier strips up multiple tracks
-	 */
-	for (ale = anim_data.last; ale; ale = ale->prev) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaTrack *nltn = nlt->next;
-		NlaStrip *strip, *stripn;
-
-		/* if this track has no tracks after it, skip for now... */
-		if (nltn == NULL)
-			continue;
-
-		/* for every selected strip, try to move */
-		for (strip = nlt->strips.first; strip; strip = stripn) {
-			stripn = strip->next;
-
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* check if the track above has room for this strip */
-				if (BKE_nlatrack_has_space(nltn, strip->start, strip->end)) {
-					/* remove from its current track, and add to the one above
-					 * (it 'should' work, so no need to worry) */
-					BLI_remlink(&nlt->strips, strip);
-					BKE_nlatrack_add_strip(nltn, strip);
-				}
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  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);
+
+  /* since we're potentially moving strips from lower tracks to higher tracks, we should
+   * loop over the tracks in reverse order to avoid moving earlier strips up multiple tracks
+   */
+  for (ale = anim_data.last; ale; ale = ale->prev) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaTrack *nltn = nlt->next;
+    NlaStrip *strip, *stripn;
+
+    /* if this track has no tracks after it, skip for now... */
+    if (nltn == NULL)
+      continue;
+
+    /* for every selected strip, try to move */
+    for (strip = nlt->strips.first; strip; strip = stripn) {
+      stripn = strip->next;
+
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* check if the track above has room for this strip */
+        if (BKE_nlatrack_has_space(nltn, strip->start, strip->end)) {
+          /* remove from its current track, and add to the one above
+           * (it 'should' work, so no need to worry) */
+          BLI_remlink(&nlt->strips, strip);
+          BKE_nlatrack_add_strip(nltn, strip);
+        }
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  /* 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_move_up(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Move Strips Up";
-	ot->idname = "NLA_OT_move_up";
-	ot->description = "Move selected strips up a track if there's room";
+  /* identifiers */
+  ot->name = "Move Strips Up";
+  ot->idname = "NLA_OT_move_up";
+  ot->description = "Move selected strips up a track if there's room";
 
-	/* api callbacks */
-	ot->exec = nlaedit_move_up_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_move_up_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Move Strips Down Operator ************************** */
@@ -1676,74 +1701,74 @@ void NLA_OT_move_up(wmOperatorType *ot)
 
 static int nlaedit_move_down_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);
-
-	/* loop through the tracks in normal order, since we're pushing strips down,
-	 * strips won't get operated on twice
-	 */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaTrack *nltp = nlt->prev;
-		NlaStrip *strip, *stripn;
-
-		/* if this track has no tracks before it, skip for now... */
-		if (nltp == NULL)
-			continue;
-
-		/* for every selected strip, try to move */
-		for (strip = nlt->strips.first; strip; strip = stripn) {
-			stripn = strip->next;
-
-			if (strip->flag & NLASTRIP_FLAG_SELECT) {
-				/* check if the track below has room for this strip */
-				if (BKE_nlatrack_has_space(nltp, strip->start, strip->end)) {
-					/* remove from its current track, and add to the one above
-					 * (it 'should' work, so no need to worry) */
-					BLI_remlink(&nlt->strips, strip);
-					BKE_nlatrack_add_strip(nltp, strip);
-				}
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  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);
+
+  /* loop through the tracks in normal order, since we're pushing strips down,
+   * strips won't get operated on twice
+   */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaTrack *nltp = nlt->prev;
+    NlaStrip *strip, *stripn;
+
+    /* if this track has no tracks before it, skip for now... */
+    if (nltp == NULL)
+      continue;
+
+    /* for every selected strip, try to move */
+    for (strip = nlt->strips.first; strip; strip = stripn) {
+      stripn = strip->next;
+
+      if (strip->flag & NLASTRIP_FLAG_SELECT) {
+        /* check if the track below has room for this strip */
+        if (BKE_nlatrack_has_space(nltp, strip->start, strip->end)) {
+          /* remove from its current track, and add to the one above
+           * (it 'should' work, so no need to worry) */
+          BLI_remlink(&nlt->strips, strip);
+          BKE_nlatrack_add_strip(nltp, strip);
+        }
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  /* 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_move_down(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Move Strips Down";
-	ot->idname = "NLA_OT_move_down";
-	ot->description = "Move selected strips down a track if there's room";
+  /* identifiers */
+  ot->name = "Move Strips Down";
+  ot->idname = "NLA_OT_move_down";
+  ot->description = "Move selected strips down a track if there's room";
 
-	/* api callbacks */
-	ot->exec = nlaedit_move_down_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_move_down_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Sync Action Length Operator ***************************** */
@@ -1751,81 +1776,87 @@ void NLA_OT_move_down(wmOperatorType *ot)
 
 static int nlaedit_sync_actlen_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-	const bool active_only = RNA_boolean_get(op->ptr, "active");
-
-	/* 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);
-	if (active_only) filter |= ANIMFILTER_ACTIVE;
-	ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
-
-	/* for each NLA-Track, apply scale of all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* strip selection/active status check */
-			if (active_only) {
-				if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
-					continue;
-			}
-			else {
-				if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
-					continue;
-			}
-
-			/* must be action-clip only (transitions don't have scale) */
-			if (strip->type == NLASTRIP_TYPE_CLIP) {
-				if (strip->act == NULL)
-					continue;
-
-				/* recalculate the length of the action */
-				calc_action_range(strip->act, &strip->actstart, &strip->actend, 0);
-
-				/* adjust the strip extents in response to this */
-				BKE_nlastrip_recalculate_bounds(strip);
-
-				ale->update |= ANIM_UPDATE_DEPS;
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+  const bool active_only = RNA_boolean_get(op->ptr, "active");
+
+  /* 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);
+  if (active_only)
+    filter |= ANIMFILTER_ACTIVE;
+  ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+
+  /* for each NLA-Track, apply scale of all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* strip selection/active status check */
+      if (active_only) {
+        if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
+          continue;
+      }
+      else {
+        if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
+          continue;
+      }
+
+      /* must be action-clip only (transitions don't have scale) */
+      if (strip->type == NLASTRIP_TYPE_CLIP) {
+        if (strip->act == NULL)
+          continue;
+
+        /* recalculate the length of the action */
+        calc_action_range(strip->act, &strip->actstart, &strip->actend, 0);
+
+        /* adjust the strip extents in response to this */
+        BKE_nlastrip_recalculate_bounds(strip);
+
+        ale->update |= ANIM_UPDATE_DEPS;
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&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_action_sync_length(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Sync Action Length";
-	ot->idname = "NLA_OT_action_sync_length";
-	ot->description = "Synchronize the length of the referenced Action with the length used in the strip";
-
-	/* api callbacks */
-	ot->exec = nlaedit_sync_actlen_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* properties */
-	ot->prop = RNA_def_boolean(ot->srna, "active", 1, "Active Strip Only", "Only sync the active length for the active strip");
+  /* identifiers */
+  ot->name = "Sync Action Length";
+  ot->idname = "NLA_OT_action_sync_length";
+  ot->description =
+      "Synchronize the length of the referenced Action with the length used in the strip";
+
+  /* api callbacks */
+  ot->exec = nlaedit_sync_actlen_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* properties */
+  ot->prop = RNA_def_boolean(ot->srna,
+                             "active",
+                             1,
+                             "Active Strip Only",
+                             "Only sync the active length for the active strip");
 }
 
 /* ******************** Make Single User ********************************* */
@@ -1833,83 +1864,83 @@ void NLA_OT_action_sync_length(wmOperatorType *ot)
 
 static int nlaedit_make_single_user_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	Main *bmain = CTX_data_main(C);
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-	bool copied = false;
-
-	/* 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(bmain, strip->act);
-
-					/* decrement user count of our existing action */
-					id_us_min(&strip->act->id);
-
-					/* switch to the new copy */
-					strip->act = new_action;
-
-					ale->update |= ANIM_UPDATE_DEPS;
-					copied = true;
-				}
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	if (copied) {
-		DEG_relations_tag_update(ac.bmain);
-	}
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  Main *bmain = CTX_data_main(C);
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+  bool copied = false;
+
+  /* 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(bmain, strip->act);
+
+          /* decrement user count of our existing action */
+          id_us_min(&strip->act->id);
+
+          /* switch to the new copy */
+          strip->act = new_action;
+
+          ale->update |= ANIM_UPDATE_DEPS;
+          copied = true;
+        }
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  if (copied) {
+    DEG_relations_tag_update(ac.bmain);
+  }
+
+  /* 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;
+  /* 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 ***************************** */
@@ -1918,108 +1949,109 @@ void NLA_OT_make_single_user(wmOperatorType *ot)
 /* apply scaling to keyframe */
 static short bezt_apply_nlamapping(KeyframeEditData *ked, BezTriple *bezt)
 {
-	/* NLA-strip which has this scaling is stored in ked->data */
-	NlaStrip *strip = (NlaStrip *)ked->data;
+  /* NLA-strip which has this scaling is stored in ked->data */
+  NlaStrip *strip = (NlaStrip *)ked->data;
 
-	/* adjust all the times */
-	bezt->vec[0][0] = nlastrip_get_frame(strip, bezt->vec[0][0], NLATIME_CONVERT_MAP);
-	bezt->vec[1][0] = nlastrip_get_frame(strip, bezt->vec[1][0], NLATIME_CONVERT_MAP);
-	bezt->vec[2][0] = nlastrip_get_frame(strip, bezt->vec[2][0], NLATIME_CONVERT_MAP);
+  /* adjust all the times */
+  bezt->vec[0][0] = nlastrip_get_frame(strip, bezt->vec[0][0], NLATIME_CONVERT_MAP);
+  bezt->vec[1][0] = nlastrip_get_frame(strip, bezt->vec[1][0], NLATIME_CONVERT_MAP);
+  bezt->vec[2][0] = nlastrip_get_frame(strip, bezt->vec[2][0], NLATIME_CONVERT_MAP);
 
-	/* nothing to return or else we exit */
-	return 0;
+  /* nothing to return or else we exit */
+  return 0;
 }
 
 static int nlaedit_apply_scale_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	Main *bmain = CTX_data_main(C);
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-	bool copied = false;
-
-	KeyframeEditData ked = {{NULL}};
-
-	/* 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);
-
-	/* for each NLA-Track, apply scale of all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* strip must be selected, and must be action-clip only
-			 * (transitions don't have scale) */
-			if ((strip->flag & NLASTRIP_FLAG_SELECT) && (strip->type == NLASTRIP_TYPE_CLIP)) {
-				/* if the referenced action is used by other strips,
-				 * make this strip use its own copy */
-				if (strip->act == NULL)
-					continue;
-				if (strip->act->id.us > 1) {
-					/* make a copy of the Action to work on */
-					bAction *act = BKE_action_copy(bmain, strip->act);
-
-					/* set this as the new referenced action,
-					 * decrementing the users of the old one */
-					id_us_min(&strip->act->id);
-					strip->act = act;
-
-					copied = true;
-				}
-
-				/* setup iterator, and iterate over all the keyframes in the action,
-				 * applying this scaling */
-				ked.data = strip;
-				ANIM_animchanneldata_keyframes_loop(&ked, ac.ads, strip->act, ALE_ACT, NULL, bezt_apply_nlamapping, calchandles_fcurve);
-
-				/* clear scale of strip now that it has been applied,
-				 * and recalculate the extents of the action now that it has been scaled
-				 * but leave everything else alone
-				 */
-				strip->scale = 1.0f;
-				calc_action_range(strip->act, &strip->actstart, &strip->actend, 0);
-
-				ale->update |= ANIM_UPDATE_DEPS;
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	if (copied) {
-		DEG_relations_tag_update(ac.bmain);
-	}
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  Main *bmain = CTX_data_main(C);
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+  bool copied = false;
+
+  KeyframeEditData ked = {{NULL}};
+
+  /* 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);
+
+  /* for each NLA-Track, apply scale of all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* strip must be selected, and must be action-clip only
+       * (transitions don't have scale) */
+      if ((strip->flag & NLASTRIP_FLAG_SELECT) && (strip->type == NLASTRIP_TYPE_CLIP)) {
+        /* if the referenced action is used by other strips,
+         * make this strip use its own copy */
+        if (strip->act == NULL)
+          continue;
+        if (strip->act->id.us > 1) {
+          /* make a copy of the Action to work on */
+          bAction *act = BKE_action_copy(bmain, strip->act);
+
+          /* set this as the new referenced action,
+           * decrementing the users of the old one */
+          id_us_min(&strip->act->id);
+          strip->act = act;
+
+          copied = true;
+        }
+
+        /* setup iterator, and iterate over all the keyframes in the action,
+         * applying this scaling */
+        ked.data = strip;
+        ANIM_animchanneldata_keyframes_loop(
+            &ked, ac.ads, strip->act, ALE_ACT, NULL, bezt_apply_nlamapping, calchandles_fcurve);
+
+        /* clear scale of strip now that it has been applied,
+         * and recalculate the extents of the action now that it has been scaled
+         * but leave everything else alone
+         */
+        strip->scale = 1.0f;
+        calc_action_range(strip->act, &strip->actstart, &strip->actend, 0);
+
+        ale->update |= ANIM_UPDATE_DEPS;
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  if (copied) {
+    DEG_relations_tag_update(ac.bmain);
+  }
+
+  /* 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_apply_scale(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Apply Scale";
-	ot->idname = "NLA_OT_apply_scale";
-	ot->description = "Apply scaling of selected strips to their referenced Actions";
+  /* identifiers */
+  ot->name = "Apply Scale";
+  ot->idname = "NLA_OT_apply_scale";
+  ot->description = "Apply scaling of selected strips to their referenced Actions";
 
-	/* api callbacks */
-	ot->exec = nlaedit_apply_scale_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_apply_scale_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Clear Scale Operator ***************************** */
@@ -2027,63 +2059,63 @@ void NLA_OT_apply_scale(wmOperatorType *ot)
 
 static int nlaedit_clear_scale_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	bAnimContext ac;
+  bAnimContext ac;
 
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
 
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
+  /* 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);
+  /* 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);
 
-	/* for each NLA-Track, reset scale of all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
+  /* for each NLA-Track, reset scale of all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
 
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* strip must be selected, and must be action-clip only
-			 * (transitions don't have scale) */
-			if ((strip->flag & NLASTRIP_FLAG_SELECT) && (strip->type == NLASTRIP_TYPE_CLIP)) {
-				PointerRNA strip_ptr;
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* strip must be selected, and must be action-clip only
+       * (transitions don't have scale) */
+      if ((strip->flag & NLASTRIP_FLAG_SELECT) && (strip->type == NLASTRIP_TYPE_CLIP)) {
+        PointerRNA strip_ptr;
 
-				RNA_pointer_create(NULL, &RNA_NlaStrip, strip, &strip_ptr);
-				RNA_float_set(&strip_ptr, "scale", 1.0f);
-			}
-		}
-	}
+        RNA_pointer_create(NULL, &RNA_NlaStrip, strip, &strip_ptr);
+        RNA_float_set(&strip_ptr, "scale", 1.0f);
+      }
+    }
+  }
 
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
 
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
 
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+  /* set notifier that things have changed */
+  WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
 
-	/* done */
-	return OPERATOR_FINISHED;
+  /* done */
+  return OPERATOR_FINISHED;
 }
 
 void NLA_OT_clear_scale(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Clear Scale";
-	ot->idname = "NLA_OT_clear_scale";
-	ot->description = "Reset scaling of selected strips";
+  /* identifiers */
+  ot->name = "Clear Scale";
+  ot->idname = "NLA_OT_clear_scale";
+  ot->description = "Reset scaling of selected strips";
 
-	/* api callbacks */
-	ot->exec = nlaedit_clear_scale_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nlaedit_clear_scale_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
 /* ******************** Snap Strips Operator ************************** */
@@ -2091,149 +2123,153 @@ void NLA_OT_clear_scale(wmOperatorType *ot)
 
 /* defines for snap keyframes tool */
 static const EnumPropertyItem prop_nlaedit_snap_types[] = {
-	{NLAEDIT_SNAP_CFRA, "CFRA", 0, "Current Frame", ""},
-	{NLAEDIT_SNAP_NEAREST_FRAME, "NEAREST_FRAME", 0, "Nearest Frame", ""}, // XXX as single entry?
-	{NLAEDIT_SNAP_NEAREST_SECOND, "NEAREST_SECOND", 0, "Nearest Second", ""}, // XXX as single entry?
-	{NLAEDIT_SNAP_NEAREST_MARKER, "NEAREST_MARKER", 0, "Nearest Marker", ""},
-	{0, NULL, 0, NULL, NULL},
+    {NLAEDIT_SNAP_CFRA, "CFRA", 0, "Current Frame", ""},
+    {NLAEDIT_SNAP_NEAREST_FRAME, "NEAREST_FRAME", 0, "Nearest Frame", ""},  // XXX as single entry?
+    {NLAEDIT_SNAP_NEAREST_SECOND,
+     "NEAREST_SECOND",
+     0,
+     "Nearest Second",
+     ""},  // XXX as single entry?
+    {NLAEDIT_SNAP_NEAREST_MARKER, "NEAREST_MARKER", 0, "Nearest Marker", ""},
+    {0, NULL, 0, NULL, NULL},
 };
 
 static int nlaedit_snap_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	Scene *scene;
-	int mode = RNA_enum_get(op->ptr, "type");
-	float secf;
-
-	/* 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);
-
-	/* get some necessary vars */
-	scene = ac.scene;
-	secf = (float)FPS;
-
-	/* since we may add tracks, perform this in reverse order */
-	for (ale = anim_data.last; ale; ale = ale->prev) {
-		ListBase tmp_strips = {NULL, NULL};
-		AnimData *adt = ale->adt;
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip, *stripn;
-		NlaTrack *track;
-
-		/* create meta-strips from the continuous chains of selected strips */
-		BKE_nlastrips_make_metas(&nlt->strips, 1);
-
-		/* apply the snapping to all the temp meta-strips, then put them in a separate list to be added
-		 * back to the original only if they still fit
-		 */
-		for (strip = nlt->strips.first; strip; strip = stripn) {
-			stripn = strip->next;
-
-			if (strip->flag & NLASTRIP_FLAG_TEMP_META) {
-				float start, end;
-
-				/* get the existing end-points */
-				start = strip->start;
-				end = strip->end;
-
-				/* calculate new start position based on snapping mode */
-				switch (mode) {
-					case NLAEDIT_SNAP_CFRA: /* to current frame */
-						strip->start = (float)CFRA;
-						break;
-					case NLAEDIT_SNAP_NEAREST_FRAME: /* to nearest frame */
-						strip->start = floorf(start + 0.5f);
-						break;
-					case NLAEDIT_SNAP_NEAREST_SECOND: /* to nearest second */
-						strip->start = floorf(start / secf + 0.5f) * secf;
-						break;
-					case NLAEDIT_SNAP_NEAREST_MARKER: /* to nearest marker */
-						strip->start = (float)ED_markers_find_nearest_marker_time(ac.markers, start);
-						break;
-					default: /* just in case... no snapping */
-						strip->start = start;
-						break;
-				}
-
-				/* get new endpoint based on start-point (and old length) */
-				strip->end = strip->start + (end - start);
-
-				/* apply transforms to meta-strip to its children */
-				BKE_nlameta_flush_transforms(strip);
-
-				/* remove strip from track, and add to the temp buffer */
-				BLI_remlink(&nlt->strips, strip);
-				BLI_addtail(&tmp_strips, strip);
-			}
-		}
-
-		/* try adding each meta-strip back to the track one at a time, to make sure they'll fit */
-		for (strip = tmp_strips.first; strip; strip = stripn) {
-			stripn = strip->next;
-
-			/* remove from temp-strips list */
-			BLI_remlink(&tmp_strips, strip);
-
-			/* in case there's no space in the current track, try adding */
-			if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
-				/* need to add a new track above the current one */
-				track = BKE_nlatrack_add(adt, nlt);
-				BKE_nlatrack_add_strip(track, strip);
-
-				/* clear temp meta-strips on this new track,
-				 * as we may not be able to get back to it */
-				BKE_nlastrips_clear_metas(&track->strips, 0, 1);
-			}
-		}
-
-		/* remove the meta-strips now that we're done */
-		BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
-
-		/* tag for recalculating the animation */
-		ale->update |= ANIM_UPDATE_DEPS;
-	}
-
-	/* cleanup */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* refresh auto strip properties */
-	ED_nla_postop_refresh(&ac);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  Scene *scene;
+  int mode = RNA_enum_get(op->ptr, "type");
+  float secf;
+
+  /* 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);
+
+  /* get some necessary vars */
+  scene = ac.scene;
+  secf = (float)FPS;
+
+  /* since we may add tracks, perform this in reverse order */
+  for (ale = anim_data.last; ale; ale = ale->prev) {
+    ListBase tmp_strips = {NULL, NULL};
+    AnimData *adt = ale->adt;
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip, *stripn;
+    NlaTrack *track;
+
+    /* create meta-strips from the continuous chains of selected strips */
+    BKE_nlastrips_make_metas(&nlt->strips, 1);
+
+    /* apply the snapping to all the temp meta-strips, then put them in a separate list to be added
+     * back to the original only if they still fit
+     */
+    for (strip = nlt->strips.first; strip; strip = stripn) {
+      stripn = strip->next;
+
+      if (strip->flag & NLASTRIP_FLAG_TEMP_META) {
+        float start, end;
+
+        /* get the existing end-points */
+        start = strip->start;
+        end = strip->end;
+
+        /* calculate new start position based on snapping mode */
+        switch (mode) {
+          case NLAEDIT_SNAP_CFRA: /* to current frame */
+            strip->start = (float)CFRA;
+            break;
+          case NLAEDIT_SNAP_NEAREST_FRAME: /* to nearest frame */
+            strip->start = floorf(start + 0.5f);
+            break;
+          case NLAEDIT_SNAP_NEAREST_SECOND: /* to nearest second */
+            strip->start = floorf(start / secf + 0.5f) * secf;
+            break;
+          case NLAEDIT_SNAP_NEAREST_MARKER: /* to nearest marker */
+            strip->start = (float)ED_markers_find_nearest_marker_time(ac.markers, start);
+            break;
+          default: /* just in case... no snapping */
+            strip->start = start;
+            break;
+        }
+
+        /* get new endpoint based on start-point (and old length) */
+        strip->end = strip->start + (end - start);
+
+        /* apply transforms to meta-strip to its children */
+        BKE_nlameta_flush_transforms(strip);
+
+        /* remove strip from track, and add to the temp buffer */
+        BLI_remlink(&nlt->strips, strip);
+        BLI_addtail(&tmp_strips, strip);
+      }
+    }
+
+    /* try adding each meta-strip back to the track one at a time, to make sure they'll fit */
+    for (strip = tmp_strips.first; strip; strip = stripn) {
+      stripn = strip->next;
+
+      /* remove from temp-strips list */
+      BLI_remlink(&tmp_strips, strip);
+
+      /* in case there's no space in the current track, try adding */
+      if (BKE_nlatrack_add_strip(nlt, strip) == 0) {
+        /* need to add a new track above the current one */
+        track = BKE_nlatrack_add(adt, nlt);
+        BKE_nlatrack_add_strip(track, strip);
+
+        /* clear temp meta-strips on this new track,
+         * as we may not be able to get back to it */
+        BKE_nlastrips_clear_metas(&track->strips, 0, 1);
+      }
+    }
+
+    /* remove the meta-strips now that we're done */
+    BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
+
+    /* tag for recalculating the animation */
+    ale->update |= ANIM_UPDATE_DEPS;
+  }
+
+  /* cleanup */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  /* refresh auto strip properties */
+  ED_nla_postop_refresh(&ac);
+
+  /* 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_snap(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Snap Strips";
-	ot->idname = "NLA_OT_snap";
-	ot->description = "Move start of strips to specified time";
+  /* identifiers */
+  ot->name = "Snap Strips";
+  ot->idname = "NLA_OT_snap";
+  ot->description = "Move start of strips to specified time";
 
-	/* api callbacks */
-	ot->invoke = WM_menu_invoke;
-	ot->exec = nlaedit_snap_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->invoke = WM_menu_invoke;
+  ot->exec = nlaedit_snap_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
-	/* properties */
-	ot->prop = RNA_def_enum(ot->srna, "type", prop_nlaedit_snap_types, 0, "Type", "");
+  /* properties */
+  ot->prop = RNA_def_enum(ot->srna, "type", prop_nlaedit_snap_types, 0, "Type", "");
 }
 
 /* *********************************************** */
@@ -2241,275 +2277,289 @@ void NLA_OT_snap(wmOperatorType *ot)
 
 /* ******************** Add F-Modifier Operator *********************** */
 
-static const EnumPropertyItem *nla_fmodifier_itemf(bContext *C, PointerRNA *UNUSED(ptr), PropertyRNA *UNUSED(prop), bool *r_free)
+static const EnumPropertyItem *nla_fmodifier_itemf(bContext *C,
+                                                   PointerRNA *UNUSED(ptr),
+                                                   PropertyRNA *UNUSED(prop),
+                                                   bool *r_free)
 {
-	EnumPropertyItem *item = NULL;
-	int totitem = 0;
-	int i = 0;
-
-	if (C == NULL) {
-		return rna_enum_fmodifier_type_items;
-	}
-
-	/* start from 1 to skip the 'Invalid' modifier type */
-	for (i = 1; i < FMODIFIER_NUM_TYPES; i++) {
-		const FModifierTypeInfo *fmi = get_fmodifier_typeinfo(i);
-		int index;
-
-		/* check if modifier is valid for this context */
-		if (fmi == NULL)
-			continue;
-		if (i == FMODIFIER_TYPE_CYCLES) /* we already have repeat... */
-			continue;
-
-		index = RNA_enum_from_value(rna_enum_fmodifier_type_items, fmi->type);
-		if (index != -1) {  /* Not all types are implemented yet... */
-			RNA_enum_item_add(&item, &totitem, &rna_enum_fmodifier_type_items[index]);
-		}
-	}
-
-	RNA_enum_item_end(&item, &totitem);
-	*r_free = true;
-
-	return item;
+  EnumPropertyItem *item = NULL;
+  int totitem = 0;
+  int i = 0;
+
+  if (C == NULL) {
+    return rna_enum_fmodifier_type_items;
+  }
+
+  /* start from 1 to skip the 'Invalid' modifier type */
+  for (i = 1; i < FMODIFIER_NUM_TYPES; i++) {
+    const FModifierTypeInfo *fmi = get_fmodifier_typeinfo(i);
+    int index;
+
+    /* check if modifier is valid for this context */
+    if (fmi == NULL)
+      continue;
+    if (i == FMODIFIER_TYPE_CYCLES) /* we already have repeat... */
+      continue;
+
+    index = RNA_enum_from_value(rna_enum_fmodifier_type_items, fmi->type);
+    if (index != -1) { /* Not all types are implemented yet... */
+      RNA_enum_item_add(&item, &totitem, &rna_enum_fmodifier_type_items[index]);
+    }
+  }
+
+  RNA_enum_item_end(&item, &totitem);
+  *r_free = true;
+
+  return item;
 }
 
-
 static int nla_fmodifier_add_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-
-	FModifier *fcm;
-	int type = RNA_enum_get(op->ptr, "type");
-	const bool active_only = RNA_boolean_get(op->ptr, "only_active");
-
-	/* 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);
-
-	/* for each NLA-Track, add the specified modifier to all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* can F-Modifier be added to the current strip? */
-			if (active_only) {
-				/* if not active, cannot add since we're only adding to active strip */
-				if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
-					continue;
-			}
-			else {
-				/* strip must be selected, since we're not just doing active */
-				if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
-					continue;
-			}
-
-			/* sound clips are not affected by FModifiers */
-			if (strip->type == NLASTRIP_TYPE_SOUND)
-				continue;
-
-			/* add F-Modifier of specified type to selected, and make it the active one */
-			fcm = add_fmodifier(&strip->modifiers, type, NULL);
-
-			if (fcm) {
-				set_active_fmodifier(&strip->modifiers, fcm);
-				ale->update |= ANIM_UPDATE_DEPS;
-			}
-			else {
-				BKE_reportf(op->reports, RPT_ERROR,
-				            "Modifier could not be added to (%s : %s) (see console for details)",
-				            nlt->name, strip->name);
-			}
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* set notifier that things have changed */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-
-	/* done */
-	return OPERATOR_FINISHED;
+  bAnimContext ac;
+
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+
+  FModifier *fcm;
+  int type = RNA_enum_get(op->ptr, "type");
+  const bool active_only = RNA_boolean_get(op->ptr, "only_active");
+
+  /* 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);
+
+  /* for each NLA-Track, add the specified modifier to all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* can F-Modifier be added to the current strip? */
+      if (active_only) {
+        /* if not active, cannot add since we're only adding to active strip */
+        if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
+          continue;
+      }
+      else {
+        /* strip must be selected, since we're not just doing active */
+        if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
+          continue;
+      }
+
+      /* sound clips are not affected by FModifiers */
+      if (strip->type == NLASTRIP_TYPE_SOUND)
+        continue;
+
+      /* add F-Modifier of specified type to selected, and make it the active one */
+      fcm = add_fmodifier(&strip->modifiers, type, NULL);
+
+      if (fcm) {
+        set_active_fmodifier(&strip->modifiers, fcm);
+        ale->update |= ANIM_UPDATE_DEPS;
+      }
+      else {
+        BKE_reportf(op->reports,
+                    RPT_ERROR,
+                    "Modifier could not be added to (%s : %s) (see console for details)",
+                    nlt->name,
+                    strip->name);
+      }
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&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_fmodifier_add(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Add F-Modifier";
-	ot->idname = "NLA_OT_fmodifier_add";
-	ot->description = "Add F-Modifier to the active/selected NLA-Strips";
-
-	/* api callbacks */
-	ot->invoke = WM_menu_invoke;
-	ot->exec = nla_fmodifier_add_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* id-props */
-	ot->prop = RNA_def_enum(ot->srna, "type", rna_enum_fmodifier_type_items, 0, "Type", "");
-	RNA_def_enum_funcs(ot->prop, nla_fmodifier_itemf);
-
-	RNA_def_boolean(ot->srna, "only_active", true, "Only Active", "Only add a F-Modifier of the specified type to the active strip");
+  /* identifiers */
+  ot->name = "Add F-Modifier";
+  ot->idname = "NLA_OT_fmodifier_add";
+  ot->description = "Add F-Modifier to the active/selected NLA-Strips";
+
+  /* api callbacks */
+  ot->invoke = WM_menu_invoke;
+  ot->exec = nla_fmodifier_add_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* id-props */
+  ot->prop = RNA_def_enum(ot->srna, "type", rna_enum_fmodifier_type_items, 0, "Type", "");
+  RNA_def_enum_funcs(ot->prop, nla_fmodifier_itemf);
+
+  RNA_def_boolean(ot->srna,
+                  "only_active",
+                  true,
+                  "Only Active",
+                  "Only add a F-Modifier of the specified type to the active strip");
 }
 
 /* ******************** Copy F-Modifiers Operator *********************** */
 
 static int nla_fmodifier_copy_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter;
-	bool ok = false;
-
-	/* get editor data */
-	if (ANIM_animdata_get_context(C, &ac) == 0)
-		return OPERATOR_CANCELLED;
-
-	/* clear buffer first */
-	ANIM_fmodifiers_copybuf_free();
-
-	/* 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);
-
-	/* for each NLA-Track, add the specified modifier to all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* only add F-Modifier if on active strip? */
-			if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
-				continue;
-
-			// TODO: when 'active' vs 'all' boolean is added, change last param!
-			ok |= ANIM_fmodifiers_copy_to_buf(&strip->modifiers, 0);
-		}
-	}
-
-	/* free temp data */
-	ANIM_animdata_freelist(&anim_data);
-
-	/* successful or not? */
-	if (ok == 0) {
-		BKE_report(op->reports, RPT_ERROR, "No F-Modifiers available to be copied");
-		return OPERATOR_CANCELLED;
-	}
-	else {
-		/* no updates needed - copy is non-destructive operation */
-		return OPERATOR_FINISHED;
-	}
+  bAnimContext ac;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter;
+  bool ok = false;
+
+  /* get editor data */
+  if (ANIM_animdata_get_context(C, &ac) == 0)
+    return OPERATOR_CANCELLED;
+
+  /* clear buffer first */
+  ANIM_fmodifiers_copybuf_free();
+
+  /* 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);
+
+  /* for each NLA-Track, add the specified modifier to all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* only add F-Modifier if on active strip? */
+      if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
+        continue;
+
+      // TODO: when 'active' vs 'all' boolean is added, change last param!
+      ok |= ANIM_fmodifiers_copy_to_buf(&strip->modifiers, 0);
+    }
+  }
+
+  /* free temp data */
+  ANIM_animdata_freelist(&anim_data);
+
+  /* successful or not? */
+  if (ok == 0) {
+    BKE_report(op->reports, RPT_ERROR, "No F-Modifiers available to be copied");
+    return OPERATOR_CANCELLED;
+  }
+  else {
+    /* no updates needed - copy is non-destructive operation */
+    return OPERATOR_FINISHED;
+  }
 }
 
 void NLA_OT_fmodifier_copy(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Copy F-Modifiers";
-	ot->idname = "NLA_OT_fmodifier_copy";
-	ot->description = "Copy the F-Modifier(s) of the active NLA-Strip";
+  /* identifiers */
+  ot->name = "Copy F-Modifiers";
+  ot->idname = "NLA_OT_fmodifier_copy";
+  ot->description = "Copy the F-Modifier(s) of the active NLA-Strip";
 
-	/* api callbacks */
-	ot->exec = nla_fmodifier_copy_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
+  /* api callbacks */
+  ot->exec = nla_fmodifier_copy_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
 
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 
-	/* id-props */
-	//ot->prop = RNA_def_boolean(ot->srna, "all", 1, "All F-Modifiers", "Copy all the F-Modifiers, instead of just the active one");
+  /* id-props */
+  //ot->prop = RNA_def_boolean(ot->srna, "all", 1, "All F-Modifiers", "Copy all the F-Modifiers, instead of just the active one");
 }
 
 /* ******************** Paste F-Modifiers Operator *********************** */
 
 static int nla_fmodifier_paste_exec(bContext *C, wmOperator *op)
 {
-	bAnimContext ac;
-	ListBase anim_data = {NULL, NULL};
-	bAnimListElem *ale;
-	int filter, ok = 0;
-
-	const bool active_only = RNA_boolean_get(op->ptr, "only_active");
-	const bool replace = RNA_boolean_get(op->ptr, "replace");
-
-	/* 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 | ANIMFILTER_NODUPLIS);
-	ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
-
-	/* for each NLA-Track, add the specified modifier to all selected strips */
-	for (ale = anim_data.first; ale; ale = ale->next) {
-		NlaTrack *nlt = (NlaTrack *)ale->data;
-		NlaStrip *strip;
-
-		for (strip = nlt->strips.first; strip; strip = strip->next) {
-			/* can F-Modifier be added to the current strip? */
-			if (active_only) {
-				/* if not active, cannot add since we're only adding to active strip */
-				if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
-					continue;
-			}
-			else {
-				/* strip must be selected, since we're not just doing active */
-				if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
-					continue;
-			}
-
-			/* paste FModifiers from buffer */
-			ok += ANIM_fmodifiers_paste_from_buf(&strip->modifiers, replace, NULL);
-			ale->update |= ANIM_UPDATE_DEPS;
-		}
-	}
-
-	/* clean up */
-	ANIM_animdata_update(&ac, &anim_data);
-	ANIM_animdata_freelist(&anim_data);
-
-	/* successful or not? */
-	if (ok) {
-		WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
-		return OPERATOR_FINISHED;
-	}
-	else {
-		BKE_report(op->reports, RPT_ERROR, "No F-Modifiers to paste");
-		return OPERATOR_CANCELLED;
-	}
+  bAnimContext ac;
+  ListBase anim_data = {NULL, NULL};
+  bAnimListElem *ale;
+  int filter, ok = 0;
+
+  const bool active_only = RNA_boolean_get(op->ptr, "only_active");
+  const bool replace = RNA_boolean_get(op->ptr, "replace");
+
+  /* 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 |
+            ANIMFILTER_NODUPLIS);
+  ANIM_animdata_filter(&ac, &anim_data, filter, ac.data, ac.datatype);
+
+  /* for each NLA-Track, add the specified modifier to all selected strips */
+  for (ale = anim_data.first; ale; ale = ale->next) {
+    NlaTrack *nlt = (NlaTrack *)ale->data;
+    NlaStrip *strip;
+
+    for (strip = nlt->strips.first; strip; strip = strip->next) {
+      /* can F-Modifier be added to the current strip? */
+      if (active_only) {
+        /* if not active, cannot add since we're only adding to active strip */
+        if ((strip->flag & NLASTRIP_FLAG_ACTIVE) == 0)
+          continue;
+      }
+      else {
+        /* strip must be selected, since we're not just doing active */
+        if ((strip->flag & NLASTRIP_FLAG_SELECT) == 0)
+          continue;
+      }
+
+      /* paste FModifiers from buffer */
+      ok += ANIM_fmodifiers_paste_from_buf(&strip->modifiers, replace, NULL);
+      ale->update |= ANIM_UPDATE_DEPS;
+    }
+  }
+
+  /* clean up */
+  ANIM_animdata_update(&ac, &anim_data);
+  ANIM_animdata_freelist(&anim_data);
+
+  /* successful or not? */
+  if (ok) {
+    WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_EDITED, NULL);
+    return OPERATOR_FINISHED;
+  }
+  else {
+    BKE_report(op->reports, RPT_ERROR, "No F-Modifiers to paste");
+    return OPERATOR_CANCELLED;
+  }
 }
 
 void NLA_OT_fmodifier_paste(wmOperatorType *ot)
 {
-	/* identifiers */
-	ot->name = "Paste F-Modifiers";
-	ot->idname = "NLA_OT_fmodifier_paste";
-	ot->description = "Add copied F-Modifiers to the selected NLA-Strips";
-
-	/* api callbacks */
-	ot->exec = nla_fmodifier_paste_exec;
-	ot->poll = nlaop_poll_tweakmode_off;
-
-	/* flags */
-	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
-
-	/* properties */
-	RNA_def_boolean(ot->srna, "only_active", true, "Only Active", "Only paste F-Modifiers on active strip");
-	RNA_def_boolean(ot->srna, "replace", false, "Replace Existing",
-	                "Replace existing F-Modifiers, instead of just appending to the end of the existing list");
+  /* identifiers */
+  ot->name = "Paste F-Modifiers";
+  ot->idname = "NLA_OT_fmodifier_paste";
+  ot->description = "Add copied F-Modifiers to the selected NLA-Strips";
+
+  /* api callbacks */
+  ot->exec = nla_fmodifier_paste_exec;
+  ot->poll = nlaop_poll_tweakmode_off;
+
+  /* flags */
+  ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  /* properties */
+  RNA_def_boolean(
+      ot->srna, "only_active", true, "Only Active", "Only paste F-Modifiers on active strip");
+  RNA_def_boolean(
+      ot->srna,
+      "replace",
+      false,
+      "Replace Existing",
+      "Replace existing F-Modifiers, instead of just appending to the end of the existing list");
 }
 
 /* *********************************************** */