3 files changed, 40 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/asset.c b/source/blender/blenkernel/intern/asset.c
index 0f62ee6df1d..427ede47272 100644
--- a/source/blender/blenkernel/intern/asset.c
+++ b/source/blender/blenkernel/intern/asset.c
@@ -26,6 +26,7 @@
 
 #include "BKE_asset.h"
 #include "BKE_icons.h"
+#include "BKE_idprop.h"
 
 #include "DNA_ID.h"
 #include "DNA_asset_types.h"
@@ -44,6 +45,9 @@ AssetData *BKE_asset_data_create(void)
 
 void BKE_asset_data_free(AssetData *asset_data)
 {
+  if (asset_data->properties) {
+    IDP_FreeProperty(asset_data->properties);
+  }
   MEM_SAFE_FREE(asset_data->description);
   BLI_freelistN(&asset_data->tags);
 
@@ -86,6 +90,10 @@ void BKE_assetdata_write(BlendWriter *writer, AssetData *asset_data)
 {
   BLO_write_struct(writer, AssetData, asset_data);
 
+  if (asset_data->properties) {
+    IDP_BlendWrite(writer, asset_data->properties);
+  }
+
   if (asset_data->description) {
     BLO_write_string(writer, asset_data->description);
   }
@@ -98,6 +106,11 @@ void BKE_assetdata_read(BlendDataReader *reader, AssetData *asset_data)
 {
   /* asset_data itself has been read already. */
 
+  if (asset_data->properties) {
+    BLO_read_data_address(reader, &asset_data->properties);
+    IDP_BlendDataRead(reader, &asset_data->properties);
+  }
+
   BLO_read_data_address(reader, &asset_data->description);
   BLO_read_list(reader, &asset_data->tags);
 }
diff --git a/source/blender/makesdna/DNA_asset_types.h b/source/blender/makesdna/DNA_asset_types.h
index ab626d73be0..b1ce2a01785 100644
--- a/source/blender/makesdna/DNA_asset_types.h
+++ b/source/blender/makesdna/DNA_asset_types.h
@@ -33,10 +33,21 @@ typedef struct CustomTag {
   char name[64]; /* MAX_NAME */
 } CustomTag;
 
+/**
+ * \brief The meta-data of an asset.
+ * By creating and giving this for a data-block (#ID.asset_data), the data-block becomes an asset.
+ *
+ * \note This struct must be readable without having to read anything but blocks from the ID it is
+ *       attached to! That way, asset information of a file can be read, without reading anything
+ *       more than that from the file. So pointers to other IDs or ID data are strictly forbidden.
+ */
 typedef struct AssetData {
   /** Thumbnail image of the data-block. Duplicate of the referenced ID preview. */
   struct PreviewImage *preview;
 
+  /** Custom asset meta-data. Cannot store pointers to IDs (#STRUCT_NO_DATABLOCK_IDPROPERTIES)! */
+  struct IDProperty *properties;
+
   /** Optional description of this asset for display in the UI. Dynamic length. */
   char *description;
   /** Optional name of the person that created this asset. */
diff --git a/source/blender/makesrna/intern/rna_asset.c b/source/blender/makesrna/intern/rna_asset.c
index 32725739cde..60eb9ffc30d 100644
--- a/source/blender/makesrna/intern/rna_asset.c
+++ b/source/blender/makesrna/intern/rna_asset.c
@@ -31,6 +31,7 @@
 #ifdef RNA_RUNTIME
 
 #  include "BKE_asset.h"
+#  include "BKE_idprop.h"
 
 #  include "RNA_access.h"
 
@@ -63,6 +64,18 @@ static void rna_AssetData_tag_remove(AssetData *asset_data,
   RNA_POINTER_INVALIDATE(tag_ptr);
 }
 
+static IDProperty *rna_AssetData_idprops(PointerRNA *ptr, bool create)
+{
+  AssetData *asset_data = ptr->data;
+
+  if (create && !asset_data->properties) {
+    IDPropertyTemplate val = {0};
+    asset_data->properties = IDP_New(IDP_GROUP, &val, "RNA_AssetData group");
+  }
+
+  return asset_data->properties;
+}
+
 static void rna_AssetData_description_get(PointerRNA *ptr, char *value)
 {
   AssetData *asset_data = ptr->data;
@@ -152,6 +165,9 @@ static void rna_def_asset_data(BlenderRNA *brna)
   srna = RNA_def_struct(brna, "AssetData", NULL);
   RNA_def_struct_ui_text(srna, "Asset Data", "Additional data stored for an asset data-block");
   //  RNA_def_struct_ui_icon(srna, ICON_ASSET); /* TODO: Icon doesn't exist!. */
+  /* The struct has custom properties, but no pointer properties to other IDs! */
+  RNA_def_struct_idprops_func(srna, "rna_AssetData_idprops");
+  RNA_def_struct_flag(srna, STRUCT_NO_DATABLOCK_IDPROPERTIES); /* Mandatory! */
 
   prop = RNA_def_property(srna, "description", PROP_STRING, PROP_NONE);
   RNA_def_property_string_funcs(prop,