source/blender/blenloader/intern/versioning_300.cc

@@ -3926,10 +3926,18 @@ void blo_do_versions_300(FileData *fd, Library * /*lib*/, Main *bmain)
             if (new_asset_shelf != nullptr) {
               new_asset_shelf->alignment = RGN_ALIGN_BOTTOM;
               new_asset_shelf->flag |= RGN_FLAG_HIDDEN;
+              new_asset_shelf->flag = RGN_FLAG_HIDDEN | RGN_FLAG_DYNAMIC_SIZE;
             }
           }
         }
       }
     }
+
+    /* Should we really use the "All" library by default? Consider loading time and memory usage.
+     */
+    LISTBASE_FOREACH (WorkSpace *, workspace, &bmain->workspaces) {
+      workspace->asset_library_ref.type = ASSET_LIBRARY_ALL;
+      workspace->asset_library_ref.custom_library_index = -1;
+    }
   }
 }

source/blender/blenloader/intern/versioning_defaults.cc

@@ -260,6 +260,9 @@ void BLO_update_defaults_workspace(WorkSpace *workspace, const char *app_templat
       BKE_workspace_tool_remove(workspace, static_cast<bToolRef *>(workspace->tools.first));
     }
 
+    workspace->asset_library_ref.type = ASSET_LIBRARY_ALL;
+    workspace->asset_library_ref.custom_library_index = -1;
+
     /* For 2D animation template. */
     if (STREQ(workspace->id.name + 2, "Drawing")) {
       workspace->object_mode = OB_MODE_PAINT_GPENCIL;

source/blender/editors/asset/ED_asset_list.h

@@ -55,8 +55,7 @@ struct ImBuf *ED_assetlist_asset_image_get(const AssetHandle *asset_handle);
 /**
  * \return True if the region needs a UI redraw.
  */
-bool ED_assetlist_listen(const struct AssetLibraryReference *library_reference,
-                         const struct wmNotifier *notifier);
+bool ED_assetlist_listen(const struct wmNotifier *notifier);
 /**
  * \return The number of assets stored in the asset list for \a library_reference, or -1 if there
  *         is no list fetched for it.

source/blender/editors/asset/intern/asset_list.cc

@@ -116,7 +116,7 @@ class AssetList : NonCopyable {
   bool isLoaded() const;
   asset_system::AssetLibrary *asset_library() const;
   void iterate(AssetListIterFn fn) const;
-  bool listen(const wmNotifier &notifier) const;
+  static bool listen(const wmNotifier &notifier);
   int size() const;
   void tagMainDataDirty() const;
   void remapID(ID *id_old, ID *id_new) const;
@@ -249,7 +249,7 @@ void AssetList::clear(bContext *C)
 /**
  * \return True if the asset-list needs a UI redraw.
  */
-bool AssetList::listen(const wmNotifier &notifier) const
+bool AssetList::listen(const wmNotifier &notifier)
 {
   switch (notifier.category) {
     case NC_ID: {
@@ -481,14 +481,9 @@ ImBuf *ED_assetlist_asset_image_get(const AssetHandle *asset_handle)
   return filelist_geticon_image_ex(asset_handle->file_data);
 }
 
-bool ED_assetlist_listen(const AssetLibraryReference *library_reference,
-                         const wmNotifier *notifier)
+bool ED_assetlist_listen(const wmNotifier *notifier)
 {
-  AssetList *list = AssetListStorage::lookup_list(*library_reference);
-  if (list) {
-    return list->listen(*notifier);
-  }
-  return false;
+  return AssetList::listen(*notifier);
 }
 
 int ED_assetlist_size(const AssetLibraryReference *library_reference)

source/blender/editors/include/ED_screen.h

@@ -122,6 +122,8 @@ void ED_region_header(const struct bContext *C, struct ARegion *region);
 void ED_region_header_layout(const struct bContext *C, struct ARegion *region);
 void ED_region_header_draw(const struct bContext *C, struct ARegion *region);
 
+void ED_region_asset_shelf_listen(const struct wmRegionListenerParams *params);
+
 void ED_region_cursor_set(struct wmWindow *win, struct ScrArea *area, struct ARegion *region);
 /**
  * Exported to all editors, uses fading default.

source/blender/editors/include/UI_interface.h

@@ -2161,6 +2161,7 @@ int uiLayoutGetAlignment(uiLayout *layout);
 bool uiLayoutGetFixedSize(uiLayout *layout);
 bool uiLayoutGetKeepAspect(uiLayout *layout);
 int uiLayoutGetWidth(uiLayout *layout);
+int uiLayoutGetRootHeight(uiLayout *layout);
 float uiLayoutGetScaleX(uiLayout *layout);
 float uiLayoutGetScaleY(uiLayout *layout);
 float uiLayoutGetUnitsX(uiLayout *layout);
@@ -2598,6 +2599,9 @@ void uiTemplateAssetView(struct uiLayout *layout,
                          struct PointerRNA *r_activate_op_properties,
                          const char *drag_opname,
                          struct PointerRNA *r_drag_op_properties);
+void uiTemplateAssetShelf(uiLayout *layout,
+                          const struct bContext *C,
+                          const struct AssetFilterSettings *filter_settings);
 
 /**
  * \return: A RNA pointer for the operator properties.

source/blender/editors/interface/CMakeLists.txt

@@ -60,6 +60,7 @@ set(SRC
   interface_region_tooltip.cc
   interface_regions.cc
   interface_style.cc
+  interface_template_asset_shelf.cc
   interface_template_asset_view.cc
   interface_template_attribute_search.cc
   interface_template_list.cc

source/blender/editors/interface/interface_layout.cc

@@ -4088,7 +4088,7 @@ static void ui_litem_layout_box(uiLayout *litem)
   const uiStyle *style = litem->root->style;
 
   int boxspace = style->boxspace;
-  if (litem->root->type == UI_LAYOUT_HEADER) {
+  if (litem->root->type == UI_LAYOUT_HEADER && false) {
     boxspace = 0;
   }
 
@@ -5117,6 +5117,11 @@ int uiLayoutGetWidth(uiLayout *layout)
   return layout->w;
 }
 
+int uiLayoutGetRootHeight(uiLayout *layout)
+{
+  return layout->root->layout->h;
+}
+
 float uiLayoutGetScaleX(uiLayout *layout)
 {
   return layout->scale[0];

source/blender/editors/interface/interface_template_asset_shelf.cc

@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/** \file
+ * \ingroup edinterface
+ */
+
+#include "BKE_context.h"
+
+#include "DNA_space_types.h"
+
+#include "ED_asset.h"
+
+#include "UI_interface.h"
+#include "UI_resources.h"
+#include "interface_intern.hh"
+
+/* TODO copy of #asset_view_item_but_drag_set(). */
+static void asset_tile_but_drag_set(uiBut &but, AssetHandle &asset_handle)
+{
+  ID *id = ED_asset_handle_get_local_id(&asset_handle);
+  if (id != nullptr) {
+    UI_but_drag_set_id(&but, id);
+    return;
+  }
+
+  char blend_path[FILE_MAX_LIBEXTRA];
+  /* Context can be null here, it's only needed for a File Browser specific hack that should go
+   * away before too long. */
+  ED_asset_handle_get_full_library_path(&asset_handle, blend_path);
+
+  if (blend_path[0]) {
+    ImBuf *imbuf = ED_assetlist_asset_image_get(&asset_handle);
+    UI_but_drag_set_asset(&but,
+                          &asset_handle,
+                          BLI_strdup(blend_path),
+                          FILE_ASSET_IMPORT_APPEND,
+                          ED_asset_handle_get_preview_icon_id(&asset_handle),
+                          imbuf,
+                          1.0f);
+  }
+}
+
+static void asset_tile_draw(uiLayout &layout,
+                            AssetHandle &asset_handle,
+                            const int width,
+                            const int height,
+                            const bool show_names)
+{
+  uiBlock *block = uiLayoutGetBlock(&layout);
+  uiBut *but = uiDefIconTextBut(block,
+                                UI_BTYPE_PREVIEW_TILE,
+                                0,
+                                ED_asset_handle_get_preview_icon_id(&asset_handle),
+                                show_names ? ED_asset_handle_get_name(&asset_handle) : "",
+                                0,
+                                0,
+                                width,
+                                height,
+                                nullptr,
+                                0,
+                                0,
+                                0,
+                                0,
+                                "");
+  ui_def_but_icon(but,
+                  ED_asset_handle_get_preview_icon_id(&asset_handle),
+                  /* NOLINTNEXTLINE: bugprone-suspicious-enum-usage */
+                  UI_HAS_ICON | UI_BUT_ICON_PREVIEW);
+  asset_tile_but_drag_set(*but, asset_handle);
+}
+
+void uiTemplateAssetShelf(uiLayout *layout,
+                          const bContext *C,
+                          const AssetFilterSettings *filter_settings)
+{
+  const AssetLibraryReference *library_ref = CTX_wm_asset_library_ref(C);
+
+  ED_assetlist_storage_fetch(library_ref, C);
+  ED_assetlist_ensure_previews_job(library_ref, C);
+  uiLayoutSetScaleX(layout, 1.0f);
+  uiLayoutSetScaleY(layout, 1.0f);
+
+  const bool show_names = true;
+  const int height = uiLayoutGetRootHeight(layout) - UI_style_get_dpi()->boxspace * 2;
+  /* Width is derived from the height. It's the height without the space for the name (if there is
+   * any). */
+  const int width = height - (show_names ? 0 : UI_UNIT_Y);
+
+  uiLayout *box = uiLayoutBox(layout);
+  uiLayout *row = uiLayoutRow(box, false);
+
+  ED_assetlist_iterate(*library_ref, [&](AssetHandle asset) {
+    if (!ED_asset_filter_matches_asset(filter_settings, &asset)) {
+      /* Don't do anything else, but return true to continue iterating. */
+      return true;
+    }
+
+    asset_tile_draw(*row, asset, width, height, show_names);
+    return true;
+  });
+}

source/blender/editors/interface/interface_template_asset_view.cc

@@ -108,9 +108,8 @@ static void asset_view_draw_item(uiList *ui_list,
   }
 }
 
-static void asset_view_listener(uiList *ui_list, wmRegionListenerParams *params)
+static void asset_view_listener(uiList * /*ui_list*/, wmRegionListenerParams *params)
 {
-  AssetViewListData *list_data = (AssetViewListData *)ui_list->dyn_data->customdata;
   const wmNotifier *notifier = params->notifier;
 
   switch (notifier->category) {
@@ -122,7 +121,7 @@ static void asset_view_listener(uiList *ui_list, wmRegionListenerParams *params)
     }
   }
 
-  if (ED_assetlist_listen(&list_data->asset_library_ref, params->notifier)) {
+  if (ED_assetlist_listen(params->notifier)) {
     ED_region_tag_redraw(params->region);
   }
 }

source/blender/editors/screen/area.c

@@ -33,6 +33,7 @@
 #include "WM_toolsystem.h"
 #include "WM_types.h"
 
+#include "ED_asset.h"
 #include "ED_buttons.h"
 #include "ED_screen.h"
 #include "ED_screen_types.h"
@@ -3311,12 +3312,15 @@ void ED_region_header_layout(const bContext *C, ARegion *region)
   bool region_layout_based = region->flag & RGN_FLAG_DYNAMIC_SIZE;
 
   /* Height of buttons and scaling needed to achieve it. */
-  const int buttony = min_ii(UI_UNIT_Y, region->winy - 2 * UI_DPI_FAC);
+  const bool is_fixed_header_height = region->type->prefsizey == HEADERY;
+  const int buttony = is_fixed_header_height ? UI_UNIT_Y :
+                                               region->winy - 2 * UI_DPI_FAC - UI_HEADER_OFFSET;
   const float buttony_scale = buttony / (float)UI_UNIT_Y;
 
   /* Vertically center buttons. */
   int xco = UI_HEADER_OFFSET;
-  int yco = buttony + (region->winy - buttony) / 2;
+  int yco = is_fixed_header_height ? buttony + (region->winy - buttony) / 2 :
+                                     buttony + UI_HEADER_OFFSET / 2;
   int maxco = xco;
 
   /* XXX workaround for 1 px alignment issue. Not sure what causes it...
@@ -3422,6 +3426,13 @@ void ED_region_header_init(ARegion *region)
   UI_view2d_region_reinit(&region->v2d, V2D_COMMONVIEW_HEADER, region->winx, region->winy);
 }
 
+void ED_region_asset_shelf_listen(const wmRegionListenerParams *params)
+{
+  if (ED_assetlist_listen(params->notifier)) {
+    ED_region_tag_redraw_no_rebuild(params->region);
+  }
+}
+
 int ED_area_headersize(void)
 {
   /* Accommodate widget and padding. */

source/blender/editors/space_view3d/space_view3d.cc

@@ -2148,10 +2148,11 @@ void ED_spacetype_view3d()
   /* regions: asset shelf */
   art = MEM_cnew<ARegionType>("spacetype view3d asset shelf region");
   art->regionid = RGN_TYPE_ASSET_SHELF;
-  art->prefsizey = HEADERY * 4;
+  art->prefsizey = HEADERY * 3.5f;
   art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_FRAMES | ED_KEYMAP_HEADER;
+  art->listener = ED_region_asset_shelf_listen;
   art->init = view3d_header_region_init;
-  art->draw = view3d_header_region_draw;
+  art->draw = ED_region_header;
   BLI_addhead(&st->regiontypes, art);
 
   /* regions: hud */

source/blender/makesdna/DNA_asset_defaults.h

@@ -20,7 +20,7 @@
 
 #define _DNA_DEFAULT_AssetLibraryReference \
   { \
-    .type = ASSET_LIBRARY_LOCAL, \
+    .type = ASSET_LIBRARY_ALL, \
     /* Not needed really (should be ignored for anything but #ASSET_LIBRARY_CUSTOM), but helps debugging. */ \
     .custom_library_index = -1, \
   }

source/blender/makesrna/intern/rna_ui_api.c

@@ -714,6 +714,15 @@ static const EnumPropertyItem *rna_uiTemplateAssetView_filter_id_types_itemf(
   return items;
 }
 
+static void rna_uiTemplateAssetShelf(uiLayout *layout, bContext *C, int filter_id_types)
+{
+  AssetFilterSettings filter_settings = {
+      .id_types = filter_id_types ? filter_id_types : FILTER_ID_ALL,
+  };
+
+  uiTemplateAssetShelf(layout, C, &filter_settings);
+}
+
 static uiLayout *rna_uiLayoutRowWithHeading(
     uiLayout *layout, bool align, const char *heading, const char *heading_ctxt, bool translate)
 {
@@ -1958,6 +1967,16 @@ void RNA_api_ui_layout(StructRNA *srna)
       "Operator properties to fill in for the custom drag operator passed to the template");
   RNA_def_parameter_flags(parm, 0, PARM_RNAPTR);
   RNA_def_function_output(func, parm);
+
+  func = RNA_def_function(srna, "template_asset_shelf", "rna_uiTemplateAssetShelf");
+  RNA_def_function_ui_description(func,
+                                  "Item. A list of assets in a horizontally scrollable layout. "
+                                  "Meant to be placed in a 'ASSET_SHELF' region");
+  RNA_def_function_flag(func, FUNC_USE_CONTEXT);
+  parm = RNA_def_property(func, "filter_id_types", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_items(parm, DummyRNA_NULL_items);
+  RNA_def_property_enum_funcs(parm, NULL, NULL, "rna_uiTemplateAssetView_filter_id_types_itemf");
+  RNA_def_property_flag(parm, PROP_ENUM_FLAG);
 }
 
 #endif