add: evaluate drivers on Python node trees

source/blender/blenkernel/BKE_animsys.h

@@ -178,6 +178,9 @@ void BKE_fcurves_main_cb(struct Main *bmain, ID_FCurve_Edit_Callback func, void
 /* Evaluation loop for evaluating animation data  */
 void BKE_animsys_evaluate_animdata(struct Scene *scene, struct ID *id, struct AnimData *adt, float ctime, short recalc);
 
+/* Evaluation loop for evaluating Python nodes trees animation data  */
+void BKE_animsys_evaluate_animdata_pyntree(struct Main *main, struct Scene *scene, float ctime, short recalc);
+
 /* Evaluation of all ID-blocks with Animation Data blocks - Animation Data Only */
 void BKE_animsys_evaluate_all_animation(struct Main *main, struct Scene *scene, float ctime);
 

source/blender/blenkernel/intern/anim_sys.c

@@ -2789,6 +2789,15 @@ void BKE_animsys_evaluate_animdata(Scene *scene, ID *id, AnimData *adt, float ct
 	adt->recalc = 0;
 }
 
+void BKE_animsys_evaluate_animdata_pyntree(struct Main *main, struct Scene *scene, float ctime, short recalc)
+{
+	for (bNodeTree *ntree = main->nodetree.first; ntree; ntree = ntree->id.next) {
+		if (ntree->type == NTREE_CUSTOM) {
+			BKE_animsys_evaluate_animdata(scene, &ntree->id, ntree->adt, ctime, recalc);
+		}
+	}
+}
+
 /* Evaluation of all ID-blocks with Animation Data blocks - Animation Data Only
  *
  * This will evaluate only the animation info available in the animation data-blocks

source/blender/blenkernel/intern/scene.c

@@ -1305,7 +1305,7 @@ void BKE_scene_frame_set(struct Scene *scene, double cfra)
  *	- these happen after objects are all done so that we can read in their final transform values,
  *	  though this means that objects can't refer to scene info for guidance...
  */
-static void scene_update_drivers(Main *UNUSED(bmain), Scene *scene)
+static void scene_update_drivers(Main *bmain, Scene *scene)
 {
 	SceneRenderLayer *srl;
 	float ctime = BKE_scene_frame_get(scene);
@@ -1334,6 +1334,9 @@ static void scene_update_drivers(Main *UNUSED(bmain), Scene *scene)
 			BKE_animsys_evaluate_animdata(scene, nid, adt, ctime, ADT_RECALC_DRIVERS);
 	}
 
+	/* A hacky way to evaluate drivers for Python nodes */
+	BKE_animsys_evaluate_animdata_pyntree(bmain, scene, ctime, ADT_RECALC_DRIVERS);
+
 	/* world nodes */
 	if (scene->world && scene->world->nodetree) {
 		ID *nid = (ID *)scene->world->nodetree;
@@ -1888,6 +1891,10 @@ void BKE_scene_update_tagged(EvaluationContext *eval_ctx, Main *bmain, Scene *sc
 #endif
 	{
 		DEG_evaluate_on_refresh(eval_ctx, scene->depsgraph, scene);
+
+		/* A hacky way to evaluate drivers for Python nodes */
+		const float ctime = BKE_scene_frame_get(scene);
+		BKE_animsys_evaluate_animdata_pyntree(bmain, scene, ctime, ADT_RECALC_DRIVERS);
 	}
 
 	/* update sound system animation (TODO, move to depsgraph) */

source/blender/editors/animation/anim_filter.c

@@ -2947,6 +2947,19 @@ static Base **animdata_filter_ds_sorted_bases(bDopeSheet *ads, Scene *scene, int
 	return sorted_bases;
 }
 
+static size_t animdata_filter_dopesheet_pyntree(bAnimContext *ac, ListBase *anim_data, bDopeSheet *ads, Scene *sce, int filter_mode)
+{
+	Main *main = (Main*)ac->bmain;
+	size_t items = 0;
+
+	for (bNodeTree *ntree = main->nodetree.first; ntree; ntree = ntree->id.next) {
+		if (ntree->type == NTREE_CUSTOM) {
+			items += animdata_filter_ds_nodetree_group(ac, anim_data, ads, &sce->id, ntree, filter_mode);
+		}
+	}
+
+	return items;
+}
 
 // TODO: implement pinning... (if and when pinning is done, what we need to do is to provide freeing mechanisms - to protect against data that was deleted)
 static size_t animdata_filter_dopesheet(bAnimContext *ac, ListBase *anim_data, bDopeSheet *ads, int filter_mode)
@@ -2982,6 +2995,9 @@ static size_t animdata_filter_dopesheet(bAnimContext *ac, ListBase *anim_data, b
 	/* scene-linked animation - e.g. world, compositing nodes, scene anim (including sequencer currently) */
 	items += animdata_filter_dopesheet_scene(ac, anim_data, ads, scene, filter_mode);
 
+	/* Python node trees */
+	items += animdata_filter_dopesheet_pyntree(ac, anim_data, ads, scene, filter_mode);
+
 	/* If filtering for channel drawing, we want the objects in alphabetical order,
 	 * to make it easier to predict where items are in the hierarchy
 	 *  - This order only really matters if we need to show all channels in the list (e.g. for drawing)