NLA SoC: More work on Meta-Strips

* Added several API functions for Meta-Strips editing. One of these (flush transform) still needs a few tweaks before it does its job well enough for all cases.

* Meta strips are now drawn with a purple-ish colour. The start/end points of the strips they encompass are shown with lines along the length of the strips, with lines starting from the top indicating start-points and lines starting from the bottom indicating end-points.

* Meta strips can be made (i.e. strips can be assigned to meta-strips) by selecting some strips and pressing Shift-G. 
Meta strips can be removed by selecting some meta-strips and pressing Alt-G.

* Strips can now be 'snapped' to start from: the current frame, the nearest frame, the nearest second, or the nearest marker; using the Shift-S hotkey. 
'Islands' of adjacent selected strips occurring in the same track are moved together as a single strip so that the start-point of the first strip is on the sepcified time, but all the relative lengths of strips stay the same. Internally, temporary meta-strips are created to facilitate this.

5 files changed, 213 insertions, 7 deletions

diff --git a/source/blender/editors/space_nla/nla_draw.c b/source/blender/editors/space_nla/nla_draw.c
index ab33434077e..e31aebf0155 100644
--- a/source/blender/editors/space_nla/nla_draw.c
+++ b/source/blender/editors/space_nla/nla_draw.c
@@ -176,6 +176,23 @@ static void nla_strip_get_color_inside (AnimData *adt, NlaStrip *strip, float co
 			color[2]= 0.19f;
 		}
 	}	
+	else if (strip->type == NLASTRIP_TYPE_META) {
+		/* Meta Clip */
+		if (strip->flag & NLASTRIP_FLAG_SELECT) {
+			/* selected - use a bold purple color */
+			// FIXME: hardcoded temp-hack colors
+			color[0]= 0.41f;
+			color[1]= 0.13f;
+			color[2]= 0.59f;
+		}
+		else {
+			/* normal, unselected strip - use (hardly noticable) dark purple tinge */
+			// FIXME: hardcoded temp-hack colors
+			color[0]= 0.20f;
+			color[1]= 0.15f;
+			color[2]= 0.26f;
+		}
+	}	
 	else {
 		/* Action Clip (default/normal type of strip) */
 		if ((strip->flag & NLASTRIP_FLAG_ACTIVE) && (adt && (adt->flag & ADT_NLA_EDIT_ON))) {
@@ -293,7 +310,7 @@ static void nla_draw_strip (AnimData *adt, NlaTrack *nlt, NlaStrip *strip, View2
 	/* draw outline */
 	gl_round_box_shade(GL_LINE_LOOP, strip->start, yminc, strip->end, ymaxc, 0.0, 0.0, 0.1);
 	
-	/* if action-clip strip, draw lines delimiting repeats too (in the same colour */
+	/* if action-clip strip, draw lines delimiting repeats too (in the same color as outline) */
 	if ((strip->type == NLASTRIP_TYPE_CLIP) && IS_EQ(strip->repeat, 1.0f)==0) {
 		float repeatLen = (strip->actend - strip->actstart) * strip->scale;
 		int i;
@@ -309,6 +326,26 @@ static void nla_draw_strip (AnimData *adt, NlaTrack *nlt, NlaStrip *strip, View2
 				fdrawline(repeatPos, yminc, repeatPos, ymaxc);
 		}
 	}
+	/* or if meta-strip, draw lines delimiting extents of sub-strips (in same color as outline, if more than 1 exists) */
+	else if ((strip->type == NLASTRIP_TYPE_META) && (strip->strips.first != strip->strips.last)) {
+		NlaStrip *cs;
+		float y= (ymaxc-yminc)/2.0f + yminc;
+		
+		/* only draw first-level of child-strips, but don't draw any lines on the endpoints */
+		for (cs= strip->strips.first; cs; cs= cs->next) {
+			/* draw start-line if not same as end of previous (and only if not the first strip) 
+			 *	- on upper half of strip
+			 */
+			if ((cs->prev) && IS_EQ(cs->prev->end, cs->start)==0)
+				fdrawline(cs->start, y, cs->start, ymaxc);
+				
+			/* draw end-line if not the last strip
+			 *	- on lower half of strip
+			 */
+			if (cs->next) 
+				fdrawline(cs->end, yminc, cs->end, y);
+		}
+	}
 	
 	/* reset linestyle */
 	setlinestyle(0);
diff --git a/source/blender/editors/space_nla/nla_edit.c b/source/blender/editors/space_nla/nla_edit.c
index e95d0b1a50a..f7d4db17e2c 100644
--- a/source/blender/editors/space_nla/nla_edit.c
+++ b/source/blender/editors/space_nla/nla_edit.c
@@ -346,7 +346,6 @@ void NLA_OT_add_actionclip (wmOperatorType *ot)
 /* ******************** Add Transition Operator ***************************** */
 /* Add a new transition strip between selected strips */
 
-/* add the specified action as new strip */
 static int nlaedit_add_transition_exec (bContext *C, wmOperator *op)
 {
 	bAnimContext ac;
@@ -453,6 +452,113 @@ void NLA_OT_add_transition (wmOperatorType *ot)
 	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
 }
 
+/* ******************** Add Meta-Strip Operator ***************************** */
+/* Add new meta-strips incorporating the selected strips */
+
+/* add the specified action as new strip */
+static int nlaedit_add_meta_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_VISIBLE | ANIMFILTER_NLATRACKS | 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;
+		
+		/* create meta-strips from the continuous chains of selected strips */
+		BKE_nlastrips_make_metas(&nlt->strips, 0);
+	}
+	
+	/* free temp data */
+	BLI_freelistN(&anim_data);
+	
+	/* set notifier that things have changed */
+	ANIM_animdata_send_notifiers(C, &ac, ANIM_CHANGED_BOTH);
+	WM_event_add_notifier(C, NC_SCENE, NULL);
+	
+	/* done */
+	return OPERATOR_FINISHED;
+}
+
+void NLA_OT_add_meta (wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Add Meta-Strips";
+	ot->idname= "NLA_OT_add_meta";
+	ot->description= "Add new meta-strips incorporating the selected strips.";
+	
+	/* api callbacks */
+	ot->exec= nlaedit_add_meta_exec;
+	ot->poll= nlaop_poll_tweakmode_off;
+	
+	/* flags */
+	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
+}
+
+/* ******************** Remove Meta-Strip Operator ***************************** */
+/* Separate out the strips held by the selected meta-strips */
+
+static int nlaedit_remove_meta_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_VISIBLE | ANIMFILTER_NLATRACKS | 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;
+		
+		/* clear all selected meta-strips, regardless of whether they are temporary or not */
+		BKE_nlastrips_clear_metas(&nlt->strips, 1, 0);
+	}
+	
+	/* free temp data */
+	BLI_freelistN(&anim_data);
+	
+	/* set notifier that things have changed */
+	ANIM_animdata_send_notifiers(C, &ac, ANIM_CHANGED_BOTH);
+	WM_event_add_notifier(C, NC_SCENE, NULL);
+	
+	/* done */
+	return OPERATOR_FINISHED;
+}
+
+void NLA_OT_remove_meta (wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Remove Meta-Strips";
+	ot->idname= "NLA_OT_remove_meta";
+	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;
+	
+	/* flags */
+	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
+}
+
 /* ******************** Duplicate Strips Operator ************************** */
 /* Duplicates the selected NLA-Strips, putting them on new tracks above the one
  * the originals were housed in.
@@ -1047,9 +1153,9 @@ static int nlaedit_snap_exec (bContext *C, wmOperator *op)
 	bAnimListElem *ale;
 	int filter;
 	
-	Scene *scene= ac.scene;
+	Scene *scene;
 	int mode = RNA_enum_get(op->ptr, "type");
-	const float secf = (float)FPS;
+	float secf;
 	
 	/* get editor data */
 	if (ANIM_animdata_get_context(C, &ac) == 0)
@@ -1059,17 +1165,28 @@ static int nlaedit_snap_exec (bContext *C, wmOperator *op)
 	filter= (ANIMFILTER_VISIBLE | ANIMFILTER_NLATRACKS | 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= BKE_animdata_from_id(ale->id);
 		NlaTrack *nlt= (NlaTrack *)ale->data;
 		NlaStrip *strip, *stripn;
+		NlaTrack *track;
 		
-		/* first pass: move all selected strips to a separate buffer, and apply snapping to them */
+		/* 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_SELECT) {
+			if (strip->flag & NLASTRIP_FLAG_TEMP_META) {
 				float start, end;
 				
 				/* get the existing end-points */
@@ -1098,13 +1215,32 @@ static int nlaedit_snap_exec (bContext *C, wmOperator *op)
 				/* 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);
 			}
 		}
 		
-		// TODO: finish this...
+		/* 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= add_nlatrack(adt, nlt);
+				BKE_nlatrack_add_strip(track, strip);
+			}
+		}
+		
+		/* remove the meta-strips now that we're done */
+		BKE_nlastrips_clear_metas(&nlt->strips, 0, 1);
 	}
 	
 	/* free temp data */
diff --git a/source/blender/editors/space_nla/nla_header.c b/source/blender/editors/space_nla/nla_header.c
index fc6db76ba65..9b9b21629cc 100644
--- a/source/blender/editors/space_nla/nla_header.c
+++ b/source/blender/editors/space_nla/nla_header.c
@@ -70,6 +70,8 @@
 
 #include "ED_markers.h"
 
+#include "nla_intern.h"
+
 /* button events */
 enum {
 	B_REDR 	= 0,
@@ -142,9 +144,18 @@ static void nla_edit_transformmenu(bContext *C, uiLayout *layout, void *arg_unus
 	uiItemEnumO(layout, "Scale", 0, "TFM_OT_transform", "mode", TFM_TIME_SCALE);
 }
 
+static void nla_edit_snapmenu(bContext *C, uiLayout *layout, void *arg_unused)
+{
+	uiItemEnumO(layout, NULL, 0, "NLA_OT_snap", "type", NLAEDIT_SNAP_CFRA);
+	uiItemEnumO(layout, NULL, 0, "NLA_OT_snap", "type", NLAEDIT_SNAP_NEAREST_FRAME);
+	uiItemEnumO(layout, NULL, 0, "NLA_OT_snap", "type", NLAEDIT_SNAP_NEAREST_SECOND);
+	uiItemEnumO(layout, NULL, 0, "NLA_OT_snap", "type", NLAEDIT_SNAP_NEAREST_MARKER);
+}
+
 static void nla_editmenu(bContext *C, uiLayout *layout, void *arg_unused)
 {
 	uiItemMenuF(layout, "Transform", 0, nla_edit_transformmenu);
+	uiItemMenuF(layout, "Snap", 0, nla_edit_snapmenu);
 	
 	uiItemS(layout);
 	
@@ -173,6 +184,11 @@ static void nla_addmenu(bContext *C, uiLayout *layout, void *arg_unused)
 	
 	uiItemS(layout);
 	
+	uiItemO(layout, NULL, 0, "NLA_OT_add_meta");
+	uiItemO(layout, NULL, 0, "NLA_OT_remove_meta");
+	
+	uiItemS(layout);
+	
 	uiItemO(layout, NULL, 0, "NLA_OT_add_tracks");
 	uiItemBooleanO(layout, "Add Tracks Above Selected", 0, "NLA_OT_add_tracks", "above_selected", 1);
 }
diff --git a/source/blender/editors/space_nla/nla_intern.h b/source/blender/editors/space_nla/nla_intern.h
index 422686bb424..4391a019207 100644
--- a/source/blender/editors/space_nla/nla_intern.h
+++ b/source/blender/editors/space_nla/nla_intern.h
@@ -106,6 +106,9 @@ void NLA_OT_tweakmode_exit(wmOperatorType *ot);
 void NLA_OT_add_actionclip(wmOperatorType *ot);
 void NLA_OT_add_transition(wmOperatorType *ot);
 
+void NLA_OT_add_meta(wmOperatorType *ot);
+void NLA_OT_remove_meta(wmOperatorType *ot);
+
 void NLA_OT_duplicate(wmOperatorType *ot);
 void NLA_OT_delete(wmOperatorType *ot);
 void NLA_OT_split(wmOperatorType *ot);
@@ -116,6 +119,8 @@ void NLA_OT_move_down(wmOperatorType *ot);
 void NLA_OT_apply_scale(wmOperatorType *ot);
 void NLA_OT_clear_scale(wmOperatorType *ot);
 
+void NLA_OT_snap(wmOperatorType *ot);
+
 void NLA_OT_fmodifier_add(wmOperatorType *ot);
 
 
diff --git a/source/blender/editors/space_nla/nla_ops.c b/source/blender/editors/space_nla/nla_ops.c
index 7caab02d6a0..25fd8db668c 100644
--- a/source/blender/editors/space_nla/nla_ops.c
+++ b/source/blender/editors/space_nla/nla_ops.c
@@ -146,6 +146,9 @@ void nla_operatortypes(void)
 	WM_operatortype_append(NLA_OT_add_actionclip);
 	WM_operatortype_append(NLA_OT_add_transition);
 	
+	WM_operatortype_append(NLA_OT_add_meta);
+	WM_operatortype_append(NLA_OT_remove_meta);
+	
 	WM_operatortype_append(NLA_OT_duplicate);
 	WM_operatortype_append(NLA_OT_delete);
 	WM_operatortype_append(NLA_OT_split);
@@ -156,6 +159,8 @@ void nla_operatortypes(void)
 	WM_operatortype_append(NLA_OT_apply_scale);
 	WM_operatortype_append(NLA_OT_clear_scale);
 	
+	WM_operatortype_append(NLA_OT_snap);
+	
 	WM_operatortype_append(NLA_OT_fmodifier_add);
 }
 
@@ -236,6 +241,10 @@ static void nla_keymap_main (wmWindowManager *wm, ListBase *keymap)
 		/* add strips */
 	WM_keymap_add_item(keymap, "NLA_OT_add_actionclip", AKEY, KM_PRESS, KM_SHIFT, 0);
 	WM_keymap_add_item(keymap, "NLA_OT_add_transition", TKEY, KM_PRESS, KM_SHIFT, 0);
+	
+		/* meta-strips */
+	WM_keymap_add_item(keymap, "NLA_OT_add_meta", GKEY, KM_PRESS, KM_SHIFT, 0);
+	WM_keymap_add_item(keymap, "NLA_OT_remove_meta", GKEY, KM_PRESS, KM_ALT, 0);
 		
 		/* duplicate */
 	WM_keymap_add_item(keymap, "NLA_OT_duplicate", DKEY, KM_PRESS, KM_SHIFT, 0);	
@@ -257,6 +266,9 @@ static void nla_keymap_main (wmWindowManager *wm, ListBase *keymap)
 		/* clear scale */
 	WM_keymap_add_item(keymap, "NLA_OT_clear_scale", SKEY, KM_PRESS, KM_ALT, 0);
 	
+		/* snap */
+	WM_keymap_add_item(keymap, "NLA_OT_snap", SKEY, KM_PRESS, KM_SHIFT, 0);
+	
 		/* add f-modifier */
 	WM_keymap_add_item(keymap, "NLA_OT_fmodifier_add", MKEY, KM_PRESS, KM_CTRL|KM_SHIFT, 0);