FileBrowser: Reduce Overhead Browsing Libraries.

When Browsing libraries the asset files were opened multiple times.
once to determine the needed groups to query and once for each
group to query the items in the group. For file browsing this makes sense
but for asset browsing this can be reduced.

This patch will load the asset files recursively and only opens them once.
Another change is that only the assets are requested and not filtered out
later in the process.

This patch is needed to simplify the library indexing. Where
we need access to the full library content.

## The numbers ##

Benchmarked by adding scenes of the spring open movie to the default
asset library. Refreshing the asset library would recursively load all the files
there.

| **8bc27c508a** | Processed 317 'directories/libraries' | 7.573986s |
| **Patch** | Processed 42 'directories/libraries' | 0.821013s |

{F10442811}

Reviewed By: mont29, Severin

Maniphest Tasks: T91406

Differential Revision: https://developer.blender.org/D12499

2 files changed, 23 insertions, 15 deletions

diff --git a/source/blender/blenloader/BLO_readfile.h b/source/blender/blenloader/BLO_readfile.h
index c8615545df9..4b4311d32bf 100644
--- a/source/blender/blenloader/BLO_readfile.h
+++ b/source/blender/blenloader/BLO_readfile.h
@@ -168,9 +168,8 @@ struct LinkNode *BLO_blendhandle_get_datablock_names(BlendHandle *bh,
 
                                                      const bool use_assets_only,
                                                      int *r_tot_names);
-struct LinkNode *BLO_blendhandle_get_datablock_info(BlendHandle *bh,
-                                                    int ofblocktype,
-                                                    int *r_tot_info_items);
+struct LinkNode * /*BLODataBlockInfo */ BLO_blendhandle_get_datablock_info(
+    BlendHandle *bh, int ofblocktype, const bool use_assets_only, int *r_tot_info_items);
 struct LinkNode *BLO_blendhandle_get_previews(BlendHandle *bh, int ofblocktype, int *r_tot_prev);
 struct PreviewImage *BLO_blendhandle_get_preview_for_id(BlendHandle *bh,
                                                         int ofblocktype,
diff --git a/source/blender/blenloader/intern/readblenentry.c b/source/blender/blenloader/intern/readblenentry.c
index f88b470809c..3306eb9e454 100644
--- a/source/blender/blenloader/intern/readblenentry.c
+++ b/source/blender/blenloader/intern/readblenentry.c
@@ -170,17 +170,19 @@ LinkNode *BLO_blendhandle_get_datablock_names(BlendHandle *bh,
 }
 
 /**
- * Gets the names and asset-data (if ID is an asset) of all the data-blocks in a file of a certain
- * type (e.g. all the scene names in a file).
+ * Gets the names and asset-data (if ID is an asset) of data-blocks in a file of a certain type.
+ * The data-blocks can be limited to assets.
  *
  * \param bh: The blendhandle to access.
  * \param ofblocktype: The type of names to get.
+ * \param use_assets_only: Limit the result to assets only.
  * \param tot_info_items: The length of the returned list.
  * \return A BLI_linklist of BLODataBlockInfo *. The links and #BLODataBlockInfo.asset_data should
  *         be freed with MEM_freeN.
  */
 LinkNode *BLO_blendhandle_get_datablock_info(BlendHandle *bh,
                                              int ofblocktype,
+                                             const bool use_assets_only,
                                              int *r_tot_info_items)
 {
   FileData *fd = (FileData *)bh;
@@ -189,27 +191,34 @@ LinkNode *BLO_blendhandle_get_datablock_info(BlendHandle *bh,
   int tot = 0;
 
   for (bhead = blo_bhead_first(fd); bhead; bhead = blo_bhead_next(fd, bhead)) {
+    if (bhead->code == ENDB) {
+      break;
+    }
     if (bhead->code == ofblocktype) {
-      struct BLODataBlockInfo *info = MEM_mallocN(sizeof(*info), __func__);
       const char *name = blo_bhead_id_name(fd, bhead) + 2;
+      AssetMetaData *asset_meta_data = blo_bhead_id_asset_data_address(fd, bhead);
 
-      STRNCPY(info->name, name);
+      const bool is_asset = asset_meta_data != NULL;
+      const bool skip_datablock = use_assets_only && !is_asset;
+      if (skip_datablock) {
+        continue;
+      }
+      struct BLODataBlockInfo *info = MEM_mallocN(sizeof(*info), __func__);
 
       /* Lastly, read asset data from the following blocks. */
-      info->asset_data = blo_bhead_id_asset_data_address(fd, bhead);
-      if (info->asset_data) {
-        bhead = blo_read_asset_data_block(fd, bhead, &info->asset_data);
-        /* blo_read_asset_data_block() reads all DATA heads and already advances bhead to the next
-         * non-DATA one. Go back, so the loop doesn't skip the non-DATA head. */
+      if (asset_meta_data) {
+        bhead = blo_read_asset_data_block(fd, bhead, &asset_meta_data);
+        /* blo_read_asset_data_block() reads all DATA heads and already advances bhead to the
+         * next non-DATA one. Go back, so the loop doesn't skip the non-DATA head. */
         bhead = blo_bhead_prev(fd, bhead);
       }
 
+      STRNCPY(info->name, name);
+      info->asset_data = asset_meta_data;
+
       BLI_linklist_prepend(&infos, info);
       tot++;
     }
-    else if (bhead->code == ENDB) {
-      break;
-    }
   }
 
   *r_tot_info_items = tot;