Select IfcProjectLibrary to display for the loaded library

Example - https://imgur.com/a/14LOL0J

src/bonsai/bonsai/bim/module/project/data.py

@@ -116,6 +116,8 @@ class ProjectLibraryData:
     def load(cls):
         cls.data = {}
         cls.data["project_libraries"] = cls.project_libraries()
+        # After .project_libraries().
+        cls.data["project_libraries_enum"] = cls.project_libraries_enum()
         cls.is_loaded = True
 
     @classmethod
@@ -129,6 +131,16 @@ class ProjectLibraryData:
             results[l.id()] = {k: v for k, v in l.get_info().items() if k in KEEP_ATTRS}
         return results
 
+    @classmethod
+    def project_libraries_enum(cls) -> list[tuple[str, str, str]]:
+        results = [
+            ("*", "All Libraries", "Show all elements"),
+            ("-", "No Library", "Show elements without library assigned"),
+        ]
+        for data in cls.data["project_libraries"].values():
+            results.append((str(data["id"]), data["Name"] or "", data["Description"] or ""))
+        return results
+
 
 class LinksData:
     linked_data = {}

src/bonsai/bonsai/bim/module/project/operator.py

@@ -214,10 +214,15 @@ class RefreshLibrary(bpy.types.Operator):
 
         self.props.active_library_element = ""
 
+        library_file = IfcStore.library_file
+        assert library_file
+
+        condition = tool.Project.get_filter_for_active_library()
         for importable_type in sorted(tool.Project.get_appendable_asset_types()):
-            if IfcStore.library_file.by_type(importable_type):
+            if (elements := library_file.by_type(importable_type)) and next(condition(elements), None):
                 new = self.props.library_elements.add()
                 new.name = importable_type
+
         return {"FINISHED"}
 
 
@@ -225,7 +230,7 @@ class ChangeLibraryElement(bpy.types.Operator):
     bl_idname = "bim.change_library_element"
     bl_label = "Change Library Element"
     bl_options = {"REGISTER", "UNDO"}
-    element_name: bpy.props.StringProperty()
+    element_name: bpy.props.StringProperty(description="IFC class to select")
 
     if TYPE_CHECKING:
         element_name: str
@@ -242,7 +247,9 @@ class ChangeLibraryElement(bpy.types.Operator):
         crumb = self.props.library_breadcrumb.add()
         crumb.name = self.element_name
 
+        filter_elements = tool.Project.get_filter_for_active_library()
         elements = self.library_file.by_type(self.element_name)
+        elements = list(filter_elements(elements))
         [ifc_classes.add(e.is_a()) for e in elements]
 
         self.props.library_elements.clear()

src/bonsai/bonsai/bim/module/project/prop.py

@@ -21,7 +21,7 @@ import bpy
 import ifcopenshell.util.element
 import ifcopenshell.util.placement
 import bonsai.tool as tool
-from bonsai.bim.module.project.data import ProjectData
+from bonsai.bim.module.project.data import ProjectData, ProjectLibraryData
 from bonsai.bim.ifc import IfcStore
 from bonsai.bim.prop import StrProperty, ObjProperty
 from bpy.types import PropertyGroup
@@ -66,6 +66,16 @@ def update_library_file(self: "BIMProjectProperties", context: bpy.types.Context
         bpy.ops.bim.select_library_file(filepath=filepath.__str__())
 
 
+def update_selected_project_library(self: "BIMProjectProperties", context: bpy.types.Context) -> None:
+    bpy.ops.bim.refresh_library()
+
+
+def get_project_libaries(self: "BIMProjectProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
+    if not ProjectLibraryData.is_loaded:
+        ProjectLibraryData.load()
+    return ProjectLibraryData.data["project_libraries_enum"]
+
+
 def update_filter_mode(self: "BIMProjectProperties", context: bpy.types.Context) -> None:
     self.filter_categories.clear()
     if self.filter_mode == "NONE":
@@ -260,7 +270,16 @@ class BIMProjectProperties(PropertyGroup):
     active_link_index: IntProperty(name="Active Link Index")
     export_schema: EnumProperty(items=get_export_schema, name="IFC Schema", update=update_export_schema)
     template_file: EnumProperty(items=get_template_file, name="Template File")
+
+    # Project library UI.
     library_file: EnumProperty(items=get_library_file, name="Library File", update=update_library_file)
+    selected_project_library: EnumProperty(
+        items=get_project_libaries,
+        name="Project Library",
+        description="Project library to display elements from",
+        update=update_selected_project_library,
+    )
+
     use_relative_project_path: BoolProperty(name="Use Relative Project Path", default=False)
     queried_obj: bpy.props.PointerProperty(type=bpy.types.Object)
     queried_obj_root: bpy.props.PointerProperty(type=bpy.types.Object)
@@ -317,7 +336,10 @@ class BIMProjectProperties(PropertyGroup):
         active_link_index: int
         export_schema: str
         template_file: str
+
         library_file: str
+        selected_project_library: Union[Literal["*", "-"], str]
+
         use_relative_project_path: bool
         queried_obj: Union[bpy.types.Object, None]
         queried_obj_root: Union[bpy.types.Object, None]

src/bonsai/bonsai/bim/module/project/ui.py

@@ -367,6 +367,7 @@ class BIM_PT_project_library(Panel):
             row = self.layout.row()
             row.label(text="No Assets Found", icon="ERROR")
             return
+        self.layout.prop(self.props, "selected_project_library", text="")
         row = self.layout.row(align=True)
         row.label(text=self.props.active_library_element or "Top Level Assets")
         if self.props.active_library_element:

src/bonsai/bonsai/tool/project.py

@@ -34,7 +34,7 @@ import bonsai.tool as tool
 from bonsai.bim.ifc import IfcStore
 from ifcopenshell.api.project.append_asset import APPENDABLE_ASSET_TYPES
 from pathlib import Path
-from typing import Optional, Union, TYPE_CHECKING
+from typing import Optional, Union, TYPE_CHECKING, Generator, Callable
 
 if TYPE_CHECKING:
     from bonsai.bim.module.project.prop import BIMProjectProperties
@@ -294,3 +294,42 @@ class Project(bonsai.core.tool.Project):
         if references_to_remove:
             for reference in references_to_remove:
                 ifcopenshell.api.document.remove_reference(ifc_file, reference)
+
+    @classmethod
+    def get_filter_for_active_library(
+        cls,
+    ) -> Callable[[list[ifcopenshell.entity_instance]], Generator[ifcopenshell.entity_instance, None, None]]:
+        props = cls.get_project_props()
+        library_file = IfcStore.library_file
+        assert library_file
+
+        if props.selected_project_library == "*":
+
+            def condition(elements: list[ifcopenshell.entity_instance]):
+                yield from elements
+
+        elif props.selected_project_library == "-":
+
+            def condition(elements: list[ifcopenshell.entity_instance]):
+                for element in elements:
+                    if not getattr(element, "HasContext", False):
+                        yield element
+
+        else:
+            project_library = library_file.by_id(int(props.selected_project_library))
+            project_library_rels = set(project_library.Declares)
+            if project_library_rels:
+
+                def condition(elements: list[ifcopenshell.entity_instance]):
+                    for element in elements:
+                        for rel in getattr(element, "HasContext", ()):
+                            if rel in project_library_rels:
+                                yield element
+                                break
+
+            else:
+
+                def condition(elements: list[ifcopenshell.entity_instance]):
+                    pass
+
+        return condition