NLA SoC: Part 1 of NLA-Data Management API

In this commit:
* Added code for freeing NLA data now stored in AnimData
* Started writing some utilities for adding NLA data, especially the 'push-down' concept for Actions
* Cleanups of existing code - removal of obsolete NLA code from various places

Next commits/parts:
* File IO code for new-style NLA data
* Version patching for old data to new data 

7 files changed, 270 insertions, 130 deletions

diff --git a/source/blender/blenkernel/BKE_nla.h b/source/blender/blenkernel/BKE_nla.h
index 230096d7ea7..0f23a5cb44d 100644
--- a/source/blender/blenkernel/BKE_nla.h
+++ b/source/blender/blenkernel/BKE_nla.h
@@ -17,12 +17,12 @@
  * along with this program; if not, write to the Free Software Foundation,
  * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  *
- * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
+ * The Original Code is Copyright (C) 2009 Blender Foundation, Joshua Leung
  * All rights reserved.
  *
  * The Original Code is: all of this file.
  *
- * Contributor(s): none yet.
+ * Contributor(s): Joshua Leung (full recode)
  *
  * ***** END GPL LICENSE BLOCK *****
  */
@@ -30,15 +30,26 @@
 #ifndef BKE_NLA_H
 #define BKE_NLA_H
 
-struct bActionStrip;
-struct ListBase;
-struct Object;
+struct AnimData;
+struct NlaStrip;
+struct NlaTrack;
+
+/* ----------------------------- */
+/* Data Management */
+
+void free_nlastrip(ListBase *strips, struct NlaStrip *strip);
+void free_nlatrack(ListBase *tracks, struct NlaTrack *nlt);
+void free_nladata(ListBase *tracks);
+
+struct NlaTrack *add_nlatrack(struct AnimData *adt);
+
+/* ----------------------------- */
+/* API */
+
+struct NlaTrack *BKE_nlatrack_find_active(ListBase *tracks);
+void BKE_nlatrack_set_active(ListBase *tracks, struct NlaTrack *nlt_a);
+
+void BKE_nla_action_pushdown(struct AnimData *adt);
 
-void free_actionstrip (struct bActionStrip* strip);
-void free_nlastrips (struct ListBase *nlalist);
-void copy_nlastrips (struct ListBase *dst, struct ListBase *src);
-void copy_actionstrip (struct bActionStrip **dst, struct bActionStrip **src);
-void find_stridechannel(struct Object *ob, struct bActionStrip *strip);
-struct bActionStrip *convert_action_to_strip (struct Object *ob);
 #endif
 
diff --git a/source/blender/blenkernel/intern/anim_sys.c b/source/blender/blenkernel/intern/anim_sys.c
index 702da23ef47..b47d734ef4f 100644
--- a/source/blender/blenkernel/intern/anim_sys.c
+++ b/source/blender/blenkernel/intern/anim_sys.c
@@ -17,6 +17,7 @@
 #include "BKE_animsys.h"
 #include "BKE_action.h"
 #include "BKE_fcurve.h"
+#include "BKE_nla.h"
 #include "BKE_global.h"
 #include "BKE_main.h"
 #include "BKE_utildefines.h"
@@ -118,6 +119,9 @@ void BKE_free_animdata (ID *id)
 			if (adt->action)
 				adt->action->id.us--;
 				
+			/* free nla data */
+			free_nladata(&adt->nla_tracks);
+			
 			/* free drivers - stored as a list of F-Curves */
 			free_fcurves(&adt->drivers);
 			
@@ -982,6 +986,9 @@ static void nladata_flush_channels (ListBase *channels)
 			case PROP_ENUM:
 				RNA_property_enum_set(ptr, prop, (int)value);
 				break;
+			default:
+				// can't do anything with other types of property....
+				break;
 		}
 	}
 }
diff --git a/source/blender/blenkernel/intern/nla.c b/source/blender/blenkernel/intern/nla.c
index dc2bf26759f..ac767fe86cc 100644
--- a/source/blender/blenkernel/intern/nla.c
+++ b/source/blender/blenkernel/intern/nla.c
@@ -17,171 +17,296 @@
  * along with this program; if not, write to the Free Software Foundation,
  * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  *
- * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
+ * The Original Code is Copyright (C) 2009 Blender Foundation, Joshua Leung
  * All rights reserved.
  *
  * The Original Code is: all of this file.
  *
- * Contributor(s): none yet.
+ * Contributor(s): Joshua Leung (full recode)
  *
  * ***** END GPL LICENSE BLOCK *****
  */
 
 #include <stdlib.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <math.h>
+#include <float.h>
 
 #include "MEM_guardedalloc.h"
 
 #include "BLI_blenlib.h"
 
-#include "DNA_space_types.h"
-#include "DNA_nla_types.h"
+#include "DNA_anim_types.h"
 #include "DNA_action_types.h"
-#include "DNA_ID.h"
-#include "DNA_ipo_types.h"
-#include "DNA_object_types.h"
 
-#include "BKE_nla.h"
+#include "BKE_animsys.h"
 #include "BKE_action.h"
+#include "BKE_fcurve.h"
+#include "BKE_nla.h"
 #include "BKE_blender.h"
 #include "BKE_library.h"
-#include "BKE_object.h" /* for convert_action_to_strip(ob) */
+#include "BKE_object.h"
+#include "BKE_utildefines.h"
 
 
 #ifdef HAVE_CONFIG_H
 #include <config.h>
 #endif
 
-/* NOTE: in group.c the strips get copied for group-nla override, this assumes
-   that strips are one single block, without additional data to be copied */
 
-void copy_actionstrip (bActionStrip **dst, bActionStrip **src){
-	bActionStrip *dstrip;
-	bActionStrip *sstrip = *src;
+/* *************************************************** */
+/* Data Management */
 
-	if (!*src){
-		*dst=NULL;
+/* Freeing ------------------------------------------- */
+
+/* Remove the given NLA strip from the NLA track it occupies, free the strip's data,
+ * and the strip itself. 
+ */
+// TODO: with things like transitions, should these get freed too? Maybe better as a UI tool
+void free_nlastrip (ListBase *strips, NlaStrip *strip)
+{
+	FModifier *fcm, *fmn;
+	
+	/* sanity checks */
+	if (strip == NULL)
 		return;
+		
+	/* remove reference to action */
+	if (strip->act)
+		strip->act->id.us--;
+		
+	/* free remapping info */
+	//if (strip->remap)
+	//	BKE_animremap_free();
+	
+	/* free own F-Curves */
+	free_fcurves(&strip->fcurves);
+	
+	/* free F-Modifiers */
+	for (fcm= strip->modifiers.first; fcm; fcm= fmn) {
+		fmn= fcm->next;
+		
+		BLI_remlink(&strip->modifiers, fcm);
+		fcurve_remove_modifier(NULL, fcm);
 	}
+	
+	/* free the strip itself */
+	if (strips)
+		BLI_freelinkN(strips, strip);
+	else
+		MEM_freeN(strip);
+}
 
-	*dst = MEM_dupallocN(sstrip);
-
-	dstrip = *dst;
-	if (dstrip->act)
-		dstrip->act->id.us++;
-
-	if (dstrip->ipo)
-		dstrip->ipo->id.us++;
+/* Remove the given NLA track from the set of NLA tracks, free the track's data,
+ * and the track itself.
+ */
+void free_nlatrack (ListBase *tracks, NlaTrack *nlt)
+{
+	NlaStrip *strip, *stripn;
 	
-	if (dstrip->modifiers.first) {
-		BLI_duplicatelist (&dstrip->modifiers, &sstrip->modifiers);
+	/* sanity checks */
+	if (nlt == NULL)
+		return;
+		
+	/* free strips */
+	for (strip= nlt->strips.first; strip; strip= stripn) {
+		stripn= strip->next;
+		free_nlastrip(&nlt->strips, strip);
 	}
 	
+	/* free NLA track itself now */
+	if (tracks)
+		BLI_freelinkN(tracks, nlt);
+	else
+		MEM_freeN(nlt);
 }
 
-void copy_nlastrips (ListBase *dst, ListBase *src)
+/* Free the elements of type NLA Tracks provided in the given list, but do not free
+ * the list itself since that is not free-standing
+ */
+void free_nladata (ListBase *tracks)
 {
-	bActionStrip *strip;
-
-	dst->first=dst->last=NULL;
-
-	BLI_duplicatelist (dst, src);
-
-	/* Update specific data */
-	if (!dst->first)
+	NlaTrack *nlt, *nltn;
+	
+	/* sanity checks */
+	if ELEM(NULL, tracks, tracks->first)
 		return;
-
-	for (strip = dst->first; strip; strip=strip->next){
-		if (strip->act)
-			strip->act->id.us++;
-		if (strip->ipo)
-			strip->ipo->id.us++;
-		if (strip->modifiers.first) {
-			ListBase listb;
-			BLI_duplicatelist (&listb, &strip->modifiers);
-			strip->modifiers= listb;
-		}
+		
+	/* free tracks one by one */
+	for (nlt= tracks->first; nlt; nlt= nltn) {
+		nltn= nlt->next;
+		free_nlatrack(tracks, nlt);
 	}
+	
+	/* clear the list's pointers to be safe */
+	tracks->first= tracks->last= NULL;
 }
 
-/* from editnla, for convert_action_to_strip -- no UI code so should be ok here.. */
-void find_stridechannel(Object *ob, bActionStrip *strip)
+/* Copying ------------------------------------------- */
+
+// TODO...
+
+/* Adding ------------------------------------------- */
+
+/* Add a NLA Strip referencing the given Action, to the given NLA Track */
+// TODO: any extra parameters to control how this is done?
+NlaStrip *add_nlastrip (NlaTrack *nlt, bAction *act)
 {
-	if(ob && ob->pose) {
-		bPoseChannel *pchan;
-		for(pchan= ob->pose->chanbase.first; pchan; pchan= pchan->next)
-			if(pchan->flag & POSE_STRIDE)
-				break;
-		if(pchan)
-			BLI_strncpy(strip->stridechannel, pchan->name, 32);
-		else
-			strip->stridechannel[0]= 0;
-	}
+	NlaStrip *strip;
+	
+	/* sanity checks */
+	if ELEM(NULL, nlt, act)
+		return NULL;
+		
+	/* allocate new strip */
+	strip= MEM_callocN(sizeof(NlaStrip), "NlaStrip");
+	BLI_addtail(&nlt->strips, strip);
+	
+	/* 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
+	 *	- (XXX) synchronisation of strip-length in accordance with changes to action-length
+	 *	  is not done though, since this should only really happens in editmode for strips now
+	 *	  though this decision is still subject to further review...
+	 */
+	strip->flag = NLASTRIP_FLAG_SELECT|NLASTRIP_FLAG_AUTO_BLENDS;
+	
+	/* assign the action reference */
+	strip->act= act;
+	id_us_plus(&act->id);
+	
+	/* determine initial range 
+	 *	- strip length cannot be 0... ever...
+	 */
+	calc_action_range(strip->act, &strip->actstart, &strip->actend, 1);
+	
+	strip->start = strip->actstart;
+	strip->end = (IS_EQ(strip->actstart, strip->actend)) ?  (strip->actstart + 1.0f): (strip->actend);
+	
+	/* strip should be referenced as-is */
+	strip->scale= 1.0f;
+	strip->repeat = 1.0f;
+	
+	/* return the new strip */
+	return strip;
 }
 
-//called by convert_nla / bpy api with an object with the action to be converted to a new strip
-bActionStrip *convert_action_to_strip (Object *ob)
+/* Add a NLA Track to the given AnimData */
+NlaTrack *add_nlatrack (AnimData *adt)
 {
-	bActionStrip *nstrip;
-
-	/* Make new actionstrip */
-	nstrip = MEM_callocN(sizeof(bActionStrip), "bActionStrip");
-			
-	/* Link the action to the nstrip */
-	nstrip->act = ob->action;
-	id_us_plus(&nstrip->act->id);
-	calc_action_range(nstrip->act, &nstrip->actstart, &nstrip->actend, 1);
-	nstrip->start = nstrip->actstart;
-	nstrip->end = nstrip->actend;
-	nstrip->flag = ACTSTRIP_SELECT|ACTSTRIP_LOCK_ACTION;
-			
-	find_stridechannel(ob, nstrip);
-	//set_active_strip(ob, nstrip); /* is in editnla as does UI calls */
-			
-	nstrip->repeat = 1.0;
-
-	if(ob->nlastrips.first == NULL)
-		ob->nlaflag |= OB_NLA_OVERRIDE;
-	
-	BLI_addtail(&ob->nlastrips, nstrip);
-	return nstrip; /* is created, malloced etc. here so is safe to just return the pointer?
-			  this is needed for setting this active in UI, and probably useful for API too */
+	NlaTrack *nlt;
+	
+	/* sanity checks */
+	if (adt == NULL)
+		return NULL;
+		
+	/* allocate new track */
+	nlt= MEM_callocN(sizeof(NlaTrack), "NlaTrack");
+	
+	/* set settings requiring the track to not be part of the stack yet */
+	nlt->flag = NLATRACK_SELECTED;
+	nlt->index= BLI_countlist(&adt->nla_tracks);
+	
+	/* add track to stack, and make it the active one */
+	BLI_addtail(&adt->nla_tracks, nlt);
+	BKE_nlatrack_set_active(&adt->nla_tracks, nlt);
+	
+	/* must have unique name, but we need to seed this */
+	sprintf(nlt->name, "NlaTrack");
+	BLI_uniquename(&adt->nla_tracks, nlt, "NlaTrack", '.', offsetof(NlaTrack, name), 64);
 	
+	/* return the new track */
+	return nlt;
 }
 
+/* *************************************************** */
+/* Basic Utilities */
 
-/* not strip itself! */
-void free_actionstrip(bActionStrip* strip)
-{
-	if (!strip)
-		return;
+/* States ------------------------------------------- */
 
-	if (strip->act){
-		strip->act->id.us--;
-		strip->act = NULL;
-	}
-	if (strip->ipo){
-		strip->ipo->id.us--;
-		strip->ipo = NULL;
-	}
-	if (strip->modifiers.first) {
-		BLI_freelistN(&strip->modifiers);
+/* Find the active NLA-track for the given stack */
+NlaTrack *BKE_nlatrack_find_active (ListBase *tracks)
+{
+	NlaTrack *nlt;
+	
+	/* sanity check */
+	if ELEM(NULL, tracks, tracks->first)
+		return NULL;
+		
+	/* try to find the first active track */
+	for (nlt= tracks->first; nlt; nlt= nlt->next) {
+		if (nlt->flag & NLATRACK_ACTIVE)
+			return nlt;
 	}
 	
+	/* none found */
+	return NULL;
 }
 
-void free_nlastrips (ListBase *nlalist)
+/* Make the given NLA-track the active one for the given stack. If no track is provided, 
+ * this function can be used to simply deactivate all the NLA tracks in the given stack too.
+ */
+void BKE_nlatrack_set_active (ListBase *tracks, NlaTrack *nlt_a)
 {
-	bActionStrip *strip;
-
-	if (!nlalist->first)
+	NlaTrack *nlt;
+	
+	/* sanity check */
+	if ELEM(NULL, tracks, tracks->first)
 		return;
+	
+	/* deactive all the rest */
+	for (nlt= tracks->first; nlt; nlt= nlt->next) 
+		nlt->flag &= ~NLATRACK_ACTIVE;
+		
+	/* set the given one as the active one */
+	if (nlt_a)
+		nlt_a->flag |= NLATRACK_ACTIVE;
+}
 
-	/* Do any specific freeing */
-	for (strip=nlalist->first; strip; strip=strip->next)
-	{
-		free_actionstrip (strip);
-	};
+/* Tools ------------------------------------------- */
 
-	/* Free the whole list */
-	BLI_freelistN(nlalist);
+/* For the given AnimData block, add the active action to the NLA
+ * stack (i.e. 'push-down' action). The UI should only allow this 
+ * for normal editing only (i.e. not in editmode for some strip's action),
+ * so no checks for this are performed.
+ */
+// TODO: maybe we should have checks for this too...
+void BKE_nla_action_pushdown (AnimData *adt)
+{
+	NlaTrack *nlt;
+	NlaStrip *strip;
+	
+	/* sanity checks */
+	// TODO: need to report the error for this
+	if ELEM(NULL, adt, adt->action) 
+		return;
+		
+	/* if the action is empty, we also shouldn't try to add to stack, 
+	 * as that will cause us grief down the track
+	 */
+	// TODO: code a method for this, and report errors after...
+		
+	/* add a new NLA track to house this action 
+	 *	- we could investigate trying to fit the action into an appropriately
+	 *	  sized gap in the existing tracks, however, this may result in unexpected 
+	 *	  changes in blending behaviour...
+	 */
+	nlt= add_nlatrack(adt);
+	if (nlt == NULL)
+		return;
+	
+	/* add a new NLA strip to the track, which references the active action */
+	strip= add_nlastrip(nlt, adt->action);
+	
+	/* clear reference to action now that we've pushed it onto the stack */
+	if (strip) {
+		adt->action->id.us--;
+		adt->action= NULL;
+	}
+	
+	// TODO: set any other flags necessary here...
 }
+
+/* *************************************************** */
diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index b913651d856..b0902784687 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -1193,18 +1193,12 @@ Object *copy_object(Object *ob)
 			armature_rebuild_pose(obn, obn->data);
 	}
 	copy_defgroups(&obn->defbase, &ob->defbase);
-#if 0 // XXX old animation system
-	copy_nlastrips(&obn->nlastrips, &ob->nlastrips);
-#endif // XXX old animation system
 	copy_constraints(&obn->constraints, &ob->constraints);
 
 	/* increase user numbers */
 	id_us_plus((ID *)obn->data);
-#if 0 // XXX old animation system
-	id_us_plus((ID *)obn->ipo);
-	id_us_plus((ID *)obn->action);
-#endif // XXX old animation system
 	id_us_plus((ID *)obn->dup_group);
+	// FIXME: add this for animdata too...
 
 	for(a=0; a<obn->totcol; a++) id_us_plus((ID *)obn->mat[a]);
 	
diff --git a/source/blender/editors/space_nla/space_nla.c b/source/blender/editors/space_nla/space_nla.c
index 6e1a97dea34..188315c73fb 100644
--- a/source/blender/editors/space_nla/space_nla.c
+++ b/source/blender/editors/space_nla/space_nla.c
@@ -29,6 +29,7 @@
 #include <string.h>
 #include <stdio.h>
 
+#include "DNA_anim_types.h"
 #include "DNA_nla_types.h"
 #include "DNA_object_types.h"
 #include "DNA_space_types.h"
diff --git a/source/blender/makesdna/DNA_anim_types.h b/source/blender/makesdna/DNA_anim_types.h
index c0cdc1ab589..b20ec7ba37f 100644
--- a/source/blender/makesdna/DNA_anim_types.h
+++ b/source/blender/makesdna/DNA_anim_types.h
@@ -395,7 +395,7 @@ typedef struct AnimMapper {
 typedef struct NlaStrip {
 	struct NlaStrip *next, *prev;
 	
-	bAction *act;				/* Action that is referenced by this strip */
+	bAction *act;				/* Action that is referenced by this strip (strip is 'user' of the action) */
 	AnimMapper *remap;			/* Remapping info this strip (for tweaking correspondance of action with context) */
 	
 	ListBase fcurves;			/* F-Curves for controlling this strip's influence and timing */	// TODO: move out?
@@ -458,6 +458,8 @@ enum {
 		/* NLA strip is muted (i.e. doesn't contribute in any way) */
 		// TODO: this overlaps a lot with the functionality in track
 	NLASTRIP_FLAG_MUTED			= (1<<12),
+		/* NLA strip length is synced to the length of the referenced action */
+	NLASTRIP_FLAG_SYNC_LENGTH	= (1<<13),
 } eNlaStrip_Flag;
 
 /* NLA Strip Type */
diff --git a/source/blender/makesdna/DNA_space_types.h b/source/blender/makesdna/DNA_space_types.h
index 0e19a6845da..0a4fe1c5814 100644
--- a/source/blender/makesdna/DNA_space_types.h
+++ b/source/blender/makesdna/DNA_space_types.h
@@ -244,7 +244,7 @@ typedef struct SpaceNla {
 
 	short blockhandler[8];
 
-	short menunr, lock;
+	int filterflag;			/* filtering flags (similar to the ones used for Keyframe Editors) */
 	short autosnap;			/* this uses the same settings as autosnap for Action Editor */
 	short flag;