Fix issues with snapping empties and faceless objects in x-ray mode.

src/bonsai/bonsai/tool/snap.py

@@ -328,8 +328,19 @@ class Snap(bonsai.core.tool.Snap):
         def cast_rays_to_single_object(
             obj: bpy.types.Object, mouse_pos: tuple[int, int]
         ) -> Union[tuple[bpy.types.Object, Vector, int], tuple[None, None, None]]:
-            if obj.type != "MESH":
+            hit = None
+            face_index = None
+            # Wireframes
+            if obj.type in {"EMPTY", "CURVE"} or (hasattr(obj.data, "polygons") and len(obj.data.polygons) == 0) :
+                snap_points = tool.Raycast.ray_cast_by_proximity(context, event, obj)
+                if snap_points:
+                    hit = sorted(snap_points, key=lambda x: x["distance"])[0]["point"]
+                    if hit:
+                        hit_world = obj.original.matrix_world @ hit
+                        return obj, hit_world, face_index
                 return None, None, None
+            # Meshes
+            else:
                 hit, normal, face_index = tool.Raycast.obj_ray_cast(context, event, obj)
                 if hit is None:
                     # Tried original mouse position. Now it will try the offsets.
@@ -407,24 +418,7 @@ class Snap(bonsai.core.tool.Snap):
                     point["group"] = "Measure"
                     detected_snaps.append(point)
 
-        # Edge-Vertex
+        # Objects
-        for obj in objs_to_raycast:
-            if obj.type in {"MESH", "EMPTY"}:
-                # if len(obj.data.polygons) == 0:
-                snap_points = tool.Raycast.ray_cast_by_proximity(context, event, obj)
-                if snap_points:
-                    for point in snap_points:
-                        point["group"] = "Edge-Vertex"
-                        detected_snaps.append(point)
-            if obj.type == "CURVE":
-                new_object = bpy.data.objects.new("new_object", obj.to_mesh().copy())
-                snap_points = tool.Raycast.ray_cast_by_proximity(context, event, new_object)
-                if snap_points:
-                    for point in snap_points:
-                        point["group"] = "Edge-Vertex"
-                        detected_snaps.append(point)
-
-        # Obj
         if (space.shading.type == "SOLID" and space.shading.show_xray) or (
             space.shading.type == "WIREFRAME" and space.shading.show_xray_wireframe
         ):
@@ -434,11 +428,41 @@ class Snap(bonsai.core.tool.Snap):
         else:
             results = []
             results.append(cast_rays_and_get_best_object(objs_to_raycast, mouse_pos))
+
         for result in results:
             snap_obj = result[0]
             hit = result[1]
             face_index = result[2]
             if hit is not None:
+                # Wireframes
+                if snap_obj.type == "EMPTY" or (snap_obj.type == "MESH" and len(snap_obj.data.polygons) == 0):
+                    snap_points = tool.Raycast.ray_cast_by_proximity(context, event, snap_obj)
+                    if snap_points:
+                        for point in snap_points:
+                            point["group"] = "Wireframe"
+                            detected_snaps.append(point)
+
+                elif snap_obj.type == "CURVE":
+                    new_object = bpy.data.objects.new("new_object", obj.to_mesh().copy())
+                    snap_points = tool.Raycast.ray_cast_by_proximity(context, event, new_object)
+                    if snap_points:
+                        for point in snap_points:
+                            point["group"] = "Wireframe"
+                            detected_snaps.append(point)
+                # Meshes
+                else:
+                    # Add face snap
+                    snap_point = {
+                        "point": hit,
+                        "type": "Face",
+                        "group": "Object",
+                        "object": snap_obj,
+                        "face_index": face_index,
+                        "distance": 9,  # High value so it has low priority
+                    }
+                    detected_snaps.append(snap_point)
+
+                    # Add vertex and edge snap
                     snap_points = tool.Raycast.ray_cast_by_proximity(
                         context, event, snap_obj, snap_obj.data.polygons[face_index]
                     )
@@ -446,16 +470,6 @@ class Snap(bonsai.core.tool.Snap):
                         for point in snap_points:
                             point["group"] = "Object"
                             detected_snaps.append(point)
-                else:
-                    snap_point = {
-                        "point": hit,
-                        "type": "Face",
-                        "group": "Object",
-                        "object": snap_obj,
-                        "face_index": face_index,
-                        "distance": 10,  # High value so it has low priority
-                    }
-                    detected_snaps.append(snap_point)
 
         # Axis and Plane
         if tool.Ifc.get():
@@ -536,7 +550,7 @@ class Snap(bonsai.core.tool.Snap):
             return filtered_points
 
         def filter_snapping_points_by_group(detected_snaps):
-            options = ["Edge-Vertex", "Axis", "Plane"]
+            options = ["Wireframe", "Axis", "Plane"]
             props = context.scene.BIMSnapGroups
             for prop in props.__annotations__.keys():
                 if getattr(props, prop):
@@ -560,7 +574,7 @@ class Snap(bonsai.core.tool.Snap):
         snaps_by_group = filter_snapping_points_by_group(detected_snaps)
         edges = []  # Get edges to create edge-intersection snap
         for snapping_point in snaps_by_group:
-            if snapping_point["group"] in {"Polyline", "Measure", "Edge-Vertex", "Object"}:
+            if snapping_point["group"] in {"Polyline", "Measure", "Wireframe", "Object"}:
                 if snapping_point["type"] == "Edge":
                     edges.append(snapping_point)
             if snapping_point["group"] == "Axis":