Todo #22395: Restoring Grease Pencil Editing Mode in DopeSheet Editor

This commit restores some basic functionality for retiming Grease
Pencil sketches. Some of the functionality that existed before still
hasn't been restored (namely snap/mirror tools as well as copy+paste),
though it should be possible to use this for basic retiming and
sketch-frame management again.

- There's still a lot of work required to get this up to the standard
of the rest of the animation editor code, as some of this code was
originally just hacked in based on the old-style code.
- Work is already required to not have to directly access the main db
global to get the list of Grease Pencil datablocks to show, but that
can come along with pending cleanups of the filtering code.

1 files changed, 55 insertions, 15 deletions

diff --git a/source/blender/editors/animation/keyframes_draw.c b/source/blender/editors/animation/keyframes_draw.c
index 5e7e071954c..12c4baaaa87 100644
--- a/source/blender/editors/animation/keyframes_draw.c
+++ b/source/blender/editors/animation/keyframes_draw.c
@@ -137,6 +137,49 @@ static void nupdate_ak_bezt (void *node, void *data)
 		ak->key_type= BEZT_KEYTYPE_KEYFRAME;
 }
 
+/* ......... */
+
+/* Comparator callback used for ActKeyColumns and GPencil frame */
+static short compare_ak_gpframe (void *node, void *data)
+{
+	ActKeyColumn *ak= (ActKeyColumn *)node;
+	bGPDframe *gpf= (bGPDframe *)data;
+	
+	if (gpf->framenum < ak->cfra)
+		return -1;
+	else if (gpf->framenum > ak->cfra)
+		return 1;
+	else
+		return 0;
+}
+
+/* New node callback used for building ActKeyColumns from GPencil frames */
+static DLRBT_Node *nalloc_ak_gpframe (void *data)
+{
+	ActKeyColumn *ak= MEM_callocN(sizeof(ActKeyColumn), "ActKeyColumnGPF");
+	bGPDframe *gpf= (bGPDframe *)data;
+	
+	/* store settings based on state of BezTriple */
+	ak->cfra= gpf->framenum;
+	ak->sel= (gpf->flag & GP_FRAME_SELECT) ? SELECT : 0;
+	
+	/* set 'modified', since this is used to identify long keyframes */
+	ak->modified = 1;
+	
+	return (DLRBT_Node *)ak;
+}
+
+/* Node updater callback used for building ActKeyColumns from GPencil frames */
+static void nupdate_ak_gpframe (void *node, void *data)
+{
+	ActKeyColumn *ak= (ActKeyColumn *)node;
+	bGPDframe *gpf= (bGPDframe *)data;
+	
+	/* set selection status and 'touched' status */
+	if (gpf->flag & GP_FRAME_SELECT) ak->sel = SELECT;
+	ak->modified += 1;
+}
+
 /* --------------- */
 
 /* Add the given BezTriple to the given 'list' of Keyframes */
@@ -148,6 +191,15 @@ static void add_bezt_to_keycolumns_list(DLRBT_Tree *keys, BezTriple *bezt)
 		BLI_dlrbTree_add(keys, compare_ak_bezt, nalloc_ak_bezt, nupdate_ak_bezt, bezt);
 }
 
+/* Add the given GPencil Frame to the given 'list' of Keyframes */
+static void add_gpframe_to_keycolumns_list(DLRBT_Tree *keys, bGPDframe *gpf)
+{
+	if ELEM(NULL, keys, gpf) 
+		return;
+	else
+		BLI_dlrbTree_add(keys, compare_ak_gpframe, nalloc_ak_gpframe, nupdate_ak_gpframe, gpf);
+}
+
 /* ActBeztColumns (Helpers for Long Keyframes) ------------------------------ */
 
 /* maximum size of default buffer for BezTriple columns */
@@ -917,23 +969,11 @@ void action_to_keylist(AnimData *adt, bAction *act, DLRBT_Tree *keys, DLRBT_Tree
 void gpl_to_keylist(bDopeSheet *UNUSED(ads), bGPDlayer *gpl, DLRBT_Tree *keys)
 {
 	bGPDframe *gpf;
-	ActKeyColumn *ak;
 	
 	if (gpl && keys) {
-		/* loop over frames, converting directly to 'keyframes' (should be in order too) */
-		for (gpf= gpl->frames.first; gpf; gpf= gpf->next) {
-			ak= MEM_callocN(sizeof(ActKeyColumn), "ActKeyColumn");
-			BLI_addtail((ListBase *)keys, ak);
-			
-			ak->cfra= (float)gpf->framenum;
-			ak->modified = 1;
-			ak->key_type= 0; 
-			
-			if (gpf->flag & GP_FRAME_SELECT)
-				ak->sel = SELECT;
-			else
-				ak->sel = 0;
-		}
+		/* although the frames should already be in an ordered list, they are not suitable for displaying yet */
+		for (gpf= gpl->frames.first; gpf; gpf= gpf->next)
+			add_gpframe_to_keycolumns_list(keys, gpf);
 	}
 }