Fix #147106: VSE: Show keyframes of compositor node trees in dopesheet

Any keyframes for properties inside the compositor node
trees that were used by strips did not show up in the dopesheet.
This was because the compositor tree is its own ID and needs to
be manually added by the dopesheet code.

This fix adds the node trees to the filtering code in
`animdata_filter_dopesheet_scene`.

Note that the dopesheet still uses the active scene as its context.
So this means that if the sequencer scene differes from the active
scene, the animation data from the sequencer scene will not
be shown. This is currently expected behavior.

Pull Request: https://projects.blender.org/blender/blender/pulls/147301

source/blender/blenkernel/intern/scene.cc

@@ -807,6 +807,8 @@ static bool strip_foreach_member_id_cb(Strip *strip, void *user_data)
   IDP_foreach_property(strip->system_properties, IDP_TYPE_FILTER_ID, [&](IDProperty *prop) {
     BKE_lib_query_idpropertiesForeachIDLink_callback(prop, data);
   });
+  /* TODO: This could use `seq::foreach_strip_modifier_id`, but because `FOREACHID_PROCESS_IDSUPER`
+   * doesn't take IDs but "ID supers", it makes it a bit more cumbersome. */
   LISTBASE_FOREACH (StripModifierData *, smd, &strip->modifiers) {
     FOREACHID_PROCESS_IDSUPER(data, smd->mask_id, IDWALK_CB_USER);
     if (smd->type == eSeqModifierType_Compositor) {

source/blender/editors/animation/anim_filter.cc

@@ -88,6 +88,8 @@
 #include "ED_anim_api.hh"
 #include "ED_markers.hh"
 
+#include "SEQ_iterator.hh"
+#include "SEQ_modifier.hh"
 #include "SEQ_sequencer.hh"
 #include "SEQ_utils.hh"
 
@@ -3444,6 +3446,7 @@ static size_t animdata_filter_dopesheet_scene(bAnimContext *ac,
   BEGIN_ANIMFILTER_SUBCHANNELS (EXPANDED_SCEC(sce)) {
     bNodeTree *ntree = sce->compositing_node_group;
     World *wo = sce->world;
+    Editing *ed = sce->ed;
 
     /* Action, Drivers, or NLA for Scene */
     if ((ac->ads->filterflag & ADS_FILTER_NOSCE) == 0) {
@@ -3461,6 +3464,23 @@ static size_t animdata_filter_dopesheet_scene(bAnimContext *ac,
           ac, &tmp_data, reinterpret_cast<ID *>(sce), ntree, filter_mode);
     }
 
+    /* Strip modifier node trees. */
+    if (ed && !(ac->ads->filterflag & ADS_FILTER_NONTREE)) {
+      VectorSet<ID *> node_trees;
+      seq::for_each_callback(&ed->seqbase, [&](Strip *strip) {
+        seq::foreach_strip_modifier_id(strip, [&](ID *id) {
+          if (GS(id->name) == ID_NT) {
+            node_trees.add(id);
+          }
+        });
+        return true;
+      });
+      for (ID *node_tree : node_trees) {
+        tmp_items += animdata_filter_ds_nodetree(
+            ac, &tmp_data, &sce->id, reinterpret_cast<bNodeTree *>(node_tree), filter_mode);
+      }
+    }
+
     /* line styles */
     if ((ac->ads->filterflag & ADS_FILTER_NOLINESTYLE) == 0) {
       tmp_items += animdata_filter_ds_linestyle(ac, &tmp_data, sce, filter_mode);

source/blender/sequencer/SEQ_modifier.hh

@@ -8,6 +8,8 @@
  * \ingroup sequencer
  */
 
+#include "BLI_function_ref.hh"
+
 #include "DNA_sequence_types.h"
 
 struct ARegionType;
@@ -17,6 +19,7 @@ struct ImBuf;
 struct ListBase;
 struct Strip;
 struct StripModifierData;
+struct ID;
 
 namespace blender::seq {
 
@@ -100,4 +103,7 @@ void modifier_set_active(Strip *strip, StripModifierData *smd);
 static constexpr char STRIP_MODIFIER_TYPE_PANEL_PREFIX[] = "STRIPMOD_PT_";
 void modifier_type_panel_id(eStripModifierType type, char *r_idname);
 
+/* Iterate over all the modifiers and call the callback function for every referenced ID. */
+void foreach_strip_modifier_id(Strip *strip, const FunctionRef<void(ID *)> fn);
+
 }  // namespace blender::seq

source/blender/sequencer/intern/modifiers/modifier.cc

@@ -621,6 +621,21 @@ void modifier_type_panel_id(eStripModifierType type, char *r_idname)
       r_idname, sizeof(PanelType::idname), STRIP_MODIFIER_TYPE_PANEL_PREFIX, mti->idname);
 }
 
+void foreach_strip_modifier_id(Strip *strip, const FunctionRef<void(ID *)> fn)
+{
+  LISTBASE_FOREACH (StripModifierData *, smd, &strip->modifiers) {
+    if (smd->mask_id) {
+      fn(reinterpret_cast<ID *>(smd->mask_id));
+    }
+    if (smd->type == eSeqModifierType_Compositor) {
+      auto *modifier_data = reinterpret_cast<SequencerCompositorModifierData *>(smd);
+      if (modifier_data->node_group) {
+        fn(reinterpret_cast<ID *>(modifier_data->node_group));
+      }
+    }
+  }
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */