ifcquery: render element types when asked

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src/ifcquery/ifcquery/render.py

@@ -24,6 +24,7 @@ import tempfile
 
 import ifcopenshell
 import ifcopenshell.geom
+import ifcopenshell.guid
 import ifcopenshell.util.selector
 
 try:
@@ -97,77 +98,18 @@ def _add_shape(
         plotter.add_mesh(mesh, color=color, opacity=opacity, show_edges=False)
 
 
-def render(
+def _render_iterator(
-    model: ifcopenshell.file,
+    iterator: object,
-    selector: str | None = None,
+    highlight_ids: list[int] | None,
-    element_ids: list[int] | None = None,
+    view: str,
-    view: str = "iso",
 ) -> bytes:
-    """Render IFC model geometry to a PNG image.
+    """Drive a geometry iterator into a pyvista plotter and return PNG bytes."""
-
-    :param model: The in-memory IFC model.
-    :param selector: ifcopenshell selector to restrict rendered elements
-        (e.g. ``'IfcWall'`` or ``'IfcBuildingStorey[Name="Ground Floor"]'``).
-        When omitted the whole model is rendered.
-    :param element_ids: Step IDs of elements to highlight. The rest of the
-        model is rendered in translucent grey so the highlighted elements
-        stand out.
-    :param view: Camera angle: ``iso``, ``top``, ``south``, ``north``,
-        ``east``, or ``west``. Defaults to ``iso``.
-    :return: PNG image as raw bytes.
-    :raises ImportError: If pyvista is not installed.
-    :raises ValueError: If the selector matches nothing or the model has no
-        renderable geometry.
-    """
-    if not _HAS_PYVISTA:
-        raise ImportError("pyvista is not installed. Install with: pip install pyvista")
-
-    settings = ifcopenshell.geom.settings()
-    settings.set("use-world-coords", True)
-
-    # Exclude 'Clearance' subcontexts (door/window operation zones) from rendering.
-    clearance_ids = {
-        c.id()
-        for c in model.by_type("IfcGeometricRepresentationSubContext")
-        if c.ContextIdentifier == "Clearance"
-    }
-    if clearance_ids:
-        ctx_ids = [
-            c.id()
-            for c in model.by_type("IfcGeometricRepresentationContext")
-            if c.id() not in clearance_ids
-        ]
-        if ctx_ids:
-            settings.set("context-ids", ctx_ids)
-
-    if selector:
-        include_elements = list(ifcopenshell.util.selector.filter_elements(model, selector))
-        if not include_elements:
-            raise ValueError(f"Selector {selector!r} matched no elements")
-        iterator = ifcopenshell.geom.iterator(
-            settings,
-            model,
-            multiprocessing.cpu_count(),
-            include=include_elements,
-        )
-    else:
-        exclude = list(model.by_type("IfcOpeningElement"))
-        iterator = ifcopenshell.geom.iterator(
-            settings,
-            model,
-            multiprocessing.cpu_count(),
-            exclude=exclude if exclude else None,
-        )
-
-    if not iterator.initialize():
-        raise ValueError("No renderable geometry found in model (or selector matched nothing)")
-
     plotter = pv.Plotter(off_screen=True, window_size=(1280, 960))
     plotter.background_color = "white"
 
     while True:
         try:
-            _add_shape(iterator.get(), plotter, highlight_ids=frozenset(element_ids) if element_ids else None)
+            _add_shape(iterator.get(), plotter, highlight_ids=frozenset(highlight_ids) if highlight_ids else None)
         except Exception:
             pass  # skip broken shapes, keep rendering the rest
         if not iterator.next():
@@ -187,3 +129,249 @@ def render(
             os.unlink(tmp_path)
         except OSError:
             pass
+
+
+def _build_geom_settings(model: ifcopenshell.file) -> "ifcopenshell.geom.settings":
+    """Build geometry settings, excluding Clearance subcontexts."""
+    settings = ifcopenshell.geom.settings()
+    settings.set("use-world-coords", True)
+
+    clearance_ids = {
+        c.id()
+        for c in model.by_type("IfcGeometricRepresentationSubContext")
+        if c.ContextIdentifier == "Clearance"
+    }
+    if clearance_ids:
+        ctx_ids = [
+            c.id()
+            for c in model.by_type("IfcGeometricRepresentationContext")
+            if c.id() not in clearance_ids
+        ]
+        if ctx_ids:
+            settings.set("context-ids", ctx_ids)
+
+    return settings
+
+
+def _get_occurrence_class(type_entity) -> str:
+    """Derive the occurrence IFC class from a type entity class name."""
+    type_class = type_entity.is_a()
+    if type_class.endswith("Type"):
+        return type_class[:-4]
+    return "IfcBuildingElementProxy"
+
+
+def _make_type_occurrence(model: ifcopenshell.file, type_entity) -> object | None:
+    """Create a temporary occurrence for *type_entity* using its RepresentationMaps.
+
+    The occurrence is added to *model* and references the type's existing
+    RepresentationMap entities via IfcMappedItem.  Returns the occurrence entity,
+    or ``None`` when the type has no usable RepresentationMaps.
+
+    .. note::
+        This function is intended for use on a temporary model copy.  The
+        caller is responsible for discarding that copy after rendering.
+    """
+    rep_maps = getattr(type_entity, "RepresentationMaps", None) or []
+    if not rep_maps:
+        return None
+
+    # One IfcMappedItem per RepresentationMap.
+    mapped_items = []
+    for rep_map in rep_maps:
+        origin = model.create_entity("IfcCartesianPoint", Coordinates=(0.0, 0.0, 0.0))
+        transform = model.create_entity(
+            "IfcCartesianTransformationOperator3D",
+            LocalOrigin=origin,
+        )
+        mapped_item = model.create_entity(
+            "IfcMappedItem",
+            MappingSource=rep_map,
+            MappingTarget=transform,
+        )
+        mapped_items.append(mapped_item)
+
+    context = rep_maps[0].MappedRepresentation.ContextOfItems
+    shape_rep = model.create_entity(
+        "IfcShapeRepresentation",
+        ContextOfItems=context,
+        RepresentationIdentifier="Body",
+        RepresentationType="MappedRepresentation",
+        Items=mapped_items,
+    )
+    prod_def_shape = model.create_entity(
+        "IfcProductDefinitionShape",
+        Representations=[shape_rep],
+    )
+
+    # Identity placement.
+    pt = model.create_entity("IfcCartesianPoint", Coordinates=(0.0, 0.0, 0.0))
+    z_dir = model.create_entity("IfcDirection", DirectionRatios=(0.0, 0.0, 1.0))
+    x_dir = model.create_entity("IfcDirection", DirectionRatios=(1.0, 0.0, 0.0))
+    axis2 = model.create_entity("IfcAxis2Placement3D", Location=pt, Axis=z_dir, RefDirection=x_dir)
+    placement = model.create_entity("IfcLocalPlacement", RelativePlacement=axis2)
+
+    occ_class = _get_occurrence_class(type_entity)
+    try:
+        occurrence = model.create_entity(
+            occ_class,
+            GlobalId=ifcopenshell.guid.new(),
+            Name=f"_type_preview_{type_entity.id()}",
+            ObjectPlacement=placement,
+            Representation=prod_def_shape,
+        )
+    except Exception:
+        occurrence = model.create_entity(
+            "IfcBuildingElementProxy",
+            GlobalId=ifcopenshell.guid.new(),
+            Name=f"_type_preview_{type_entity.id()}",
+            ObjectPlacement=placement,
+            Representation=prod_def_shape,
+        )
+    return occurrence
+
+
+def _render_with_types(
+    model: ifcopenshell.file,
+    types: list,
+    selector_elements: list | None,
+    element_ids: list[int] | None,
+    type_highlight_ids: set[int],
+    view: str,
+) -> bytes:
+    """Render type entities by creating occurrences in a temporary model copy.
+
+    *types* — list of IfcTypeProduct entities to render.
+    *selector_elements* — non-type elements from the selector (or ``None``).
+    *element_ids* — original highlight IDs (may contain type IDs).
+    *type_highlight_ids* — subset of *element_ids* that are type IDs.
+    """
+    tmp_fd, tmp_path = tempfile.mkstemp(suffix=".ifc")
+    os.close(tmp_fd)
+    try:
+        model.write(tmp_path)
+        tmp = ifcopenshell.open(tmp_path)
+
+        # Map original type step-ID → new occurrence step-ID in the tmp model.
+        type_id_to_occ_id: dict[int, int] = {}
+        for t in types:
+            tmp_type = tmp.by_id(t.id())
+            occ = _make_type_occurrence(tmp, tmp_type)
+            if occ:
+                type_id_to_occ_id[t.id()] = occ.id()
+
+        if not type_id_to_occ_id:
+            raise ValueError("Type entities have no RepresentationMaps to render")
+
+        include = [tmp.by_id(occ_id) for occ_id in type_id_to_occ_id.values()]
+        if selector_elements:
+            include.extend(tmp.by_id(e.id()) for e in selector_elements)
+
+        settings = _build_geom_settings(tmp)
+        iterator = ifcopenshell.geom.iterator(settings, tmp, multiprocessing.cpu_count(), include=include)
+        if not iterator.initialize():
+            raise ValueError("Type entities have no renderable geometry")
+
+        # Remap type IDs → occurrence IDs in the highlight list.
+        new_highlight = None
+        if element_ids:
+            new_highlight = []
+            for hid in element_ids:
+                if hid in type_highlight_ids:
+                    mapped = type_id_to_occ_id.get(hid)
+                    if mapped:
+                        new_highlight.append(mapped)
+                else:
+                    new_highlight.append(hid)
+
+        return _render_iterator(iterator, new_highlight, view)
+    finally:
+        try:
+            os.unlink(tmp_path)
+        except OSError:
+            pass
+
+
+def render(
+    model: ifcopenshell.file,
+    selector: str | None = None,
+    element_ids: list[int] | None = None,
+    view: str = "iso",
+) -> bytes:
+    """Render IFC model geometry to a PNG image.
+
+    Supports both element instances and element types (e.g. ``IfcWallType``).
+    When type entities are targeted — via *selector* or *element_ids* — a
+    temporary copy of the model is used to create proxy occurrences that
+    reference the type's RepresentationMaps; the original model is not
+    modified.
+
+    :param model: The in-memory IFC model.
+    :param selector: ifcopenshell selector to restrict rendered elements
+        (e.g. ``'IfcWall'``, ``'IfcWallType'``, or
+        ``'IfcBuildingStorey[Name="Ground Floor"]'``).
+        When omitted the whole model is rendered.
+    :param element_ids: Step IDs of elements (or types) to highlight. The
+        rest of the model is rendered in translucent grey so the highlighted
+        items stand out.
+    :param view: Camera angle: ``iso``, ``top``, ``south``, ``north``,
+        ``east``, or ``west``. Defaults to ``iso``.
+    :return: PNG image as raw bytes.
+    :raises ImportError: If pyvista is not installed.
+    :raises ValueError: If the selector matches nothing or the model has no
+        renderable geometry.
+    """
+    if not _HAS_PYVISTA:
+        raise ImportError("pyvista is not installed. Install with: pip install pyvista")
+
+    # --- Partition selector results into types and elements ---
+    if selector:
+        matched = list(ifcopenshell.util.selector.filter_elements(model, selector))
+        if not matched:
+            raise ValueError(f"Selector {selector!r} matched no elements")
+        types = [e for e in matched if e.is_a("IfcTypeProduct")]
+        selector_elements: list | None = [e for e in matched if not e.is_a("IfcTypeProduct")]
+    else:
+        types = []
+        selector_elements = None  # no restriction — render all elements
+
+    # --- Collect any type entities from element_ids ---
+    type_highlight_ids: set[int] = set()
+    if element_ids:
+        for eid in element_ids:
+            entity = model.by_id(eid)
+            if entity.is_a("IfcTypeProduct"):
+                type_highlight_ids.add(eid)
+                seen = {t.id() for t in types}
+                if eid not in seen:
+                    types.append(entity)
+
+    # --- Delegate to temp-copy path when any type entities are involved ---
+    if types:
+        return _render_with_types(model, types, selector_elements, element_ids, type_highlight_ids, view)
+
+    # --- Regular element rendering ---
+    settings = _build_geom_settings(model)
+
+    if selector_elements is not None:
+        if not selector_elements:
+            raise ValueError(f"Selector {selector!r} matched only type entities (use a type selector or IfcElement)")
+        iterator = ifcopenshell.geom.iterator(
+            settings,
+            model,
+            multiprocessing.cpu_count(),
+            include=selector_elements,
+        )
+    else:
+        exclude = list(model.by_type("IfcOpeningElement"))
+        iterator = ifcopenshell.geom.iterator(
+            settings,
+            model,
+            multiprocessing.cpu_count(),
+            exclude=exclude if exclude else None,
+        )
+
+    if not iterator.initialize():
+        raise ValueError("No renderable geometry found in model (or selector matched nothing)")
+
+    return _render_iterator(iterator, element_ids, view)

src/ifcquery/tests/test_render.py

@@ -16,7 +16,7 @@ import ifcopenshell.api.unit
 import numpy as np
 import pytest
 
-from ifcquery.render import render
+from ifcquery.render import render, _make_type_occurrence
 
 try:
     import pyvista  # noqa: F401
@@ -69,6 +69,35 @@ def model_with_geometry():
     return f
 
 
+@pytest.fixture
+def library_with_type():
+    """IFC4 library file: a WallType with a RepresentationMap but no instances."""
+    f = ifcopenshell.api.project.create_file()
+    ifcopenshell.api.owner.settings.get_user = lambda ifc: (ifc.by_type("IfcPersonAndOrganization") or [None])[0]
+    ifcopenshell.api.owner.settings.get_application = lambda ifc: (ifc.by_type("IfcApplication") or [None])[0]
+
+    project = ifcopenshell.api.root.create_entity(f, ifc_class="IfcProject", name="LibProject")
+    ifcopenshell.api.unit.assign_unit(f)
+
+    model_ctx = ifcopenshell.api.context.add_context(f, context_type="Model")
+    body = ifcopenshell.api.context.add_context(
+        f, context_type="Model", context_identifier="Body", target_view="MODEL_VIEW", parent=model_ctx
+    )
+
+    # Build the shape representation and wrap it in an IfcRepresentationMap.
+    shape_rep = ifcopenshell.api.geometry.add_wall_representation(f, context=body, length=3, height=2.5, thickness=0.2)
+    origin = f.create_entity("IfcCartesianPoint", Coordinates=(0.0, 0.0, 0.0))
+    z_dir = f.create_entity("IfcDirection", DirectionRatios=(0.0, 0.0, 1.0))
+    x_dir = f.create_entity("IfcDirection", DirectionRatios=(1.0, 0.0, 0.0))
+    map_origin = f.create_entity("IfcAxis2Placement3D", Location=origin, Axis=z_dir, RefDirection=x_dir)
+    rep_map = f.create_entity("IfcRepresentationMap", MappingOrigin=map_origin, MappedRepresentation=shape_rep)
+
+    wall_type = ifcopenshell.api.root.create_entity(f, ifc_class="IfcWallType", name="LibWallType")
+    wall_type.RepresentationMaps = [rep_map]
+
+    return f, wall_type
+
+
 class TestRenderBasic:
     def test_returns_png_bytes(self, model_with_geometry):
         result = render(model_with_geometry)
@@ -115,6 +144,44 @@ class TestRenderHighlight:
         assert result[:4] == PNG_MAGIC
 
 
+class TestRenderTypes:
+    def test_render_type_by_selector(self, library_with_type):
+        """Selecting a type class renders its RepresentationMap geometry."""
+        model, wall_type = library_with_type
+        result = render(model, selector="IfcWallType")
+        assert result[:4] == PNG_MAGIC
+
+    def test_render_type_by_element_id(self, library_with_type):
+        """Passing a type step-ID via element_ids renders it highlighted."""
+        model, wall_type = library_with_type
+        result = render(model, element_ids=[wall_type.id()])
+        assert result[:4] == PNG_MAGIC
+
+    def test_original_model_unmodified(self, library_with_type):
+        """Rendering a type must not add entities to the original model."""
+        model, wall_type = library_with_type
+        entity_count_before = len(list(model))
+        render(model, selector="IfcWallType")
+        assert len(list(model)) == entity_count_before
+
+    def test_make_type_occurrence_no_rep_maps(self, library_with_type):
+        """_make_type_occurrence returns None for a type with no RepresentationMaps."""
+        model, _ = library_with_type
+        bare_type = ifcopenshell.api.root.create_entity(model, ifc_class="IfcWallType", name="Bare")
+        assert _make_type_occurrence(model, bare_type) is None
+
+    def test_type_without_rep_maps_raises(self):
+        """Selecting a type that has no RepresentationMaps raises ValueError."""
+        f = ifcopenshell.api.project.create_file()
+        ifcopenshell.api.owner.settings.get_user = lambda ifc: (ifc.by_type("IfcPersonAndOrganization") or [None])[0]
+        ifcopenshell.api.owner.settings.get_application = lambda ifc: (ifc.by_type("IfcApplication") or [None])[0]
+        ifcopenshell.api.root.create_entity(f, ifc_class="IfcProject", name="P")
+        ifcopenshell.api.unit.assign_unit(f)
+        ifcopenshell.api.root.create_entity(f, ifc_class="IfcWallType", name="Bare")
+        with pytest.raises(ValueError):
+            render(f, selector="IfcWallType")
+
+
 class TestRenderNoGeometry:
     def test_no_geometry_raises(self):
         """A model without geometry representations raises ValueError."""