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.

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_nla.h b/source/blender/blenkernel/BKE_nla.h
index efa0591bd53..3fcd799310e 100644
--- a/source/blender/blenkernel/BKE_nla.h
+++ b/source/blender/blenkernel/BKE_nla.h
@@ -58,6 +58,12 @@ void BKE_nlastrips_sort_strips(ListBase *strips);
 
 short BKE_nlastrips_add_strip(ListBase *strips, struct NlaStrip *strip);
 
+
+void BKE_nlastrips_make_metas(ListBase *strips, short temp);
+void BKE_nlastrips_clear_metas(ListBase *strips, short onlySel, short onlyTemp);
+short BKE_nlameta_add_strip(struct NlaStrip *mstrip, struct NlaStrip *strip);
+void BKE_nlameta_flush_transforms(struct NlaStrip *mstrip);
+
 /* ............ */
 
 struct NlaTrack *BKE_nlatrack_find_active(ListBase *tracks);