Fix optional viser import and add Space caption metadata

README.md

@@ -1,5 +1,6 @@
 ---
 title: LingBot 3D
+short_description: Streaming 3D scene reconstruction from short clips.
 colorFrom: blue
 colorTo: green
 sdk: gradio

lingbot_map/vis/__init__.py

@@ -1,59 +1,47 @@
-# Copyright (c) Meta Platforms, Inc. and affiliates.
-# All rights reserved.
-#
-# This source code is licensed under the license found in the
-# LICENSE file in the root directory of this source tree.
-
 """
-GCT Visualization Module
-
-This module provides visualization utilities for 3D reconstruction results:
-- PointCloudViewer: Interactive point cloud viewer with camera visualization
-- viser_wrapper: Quick visualization wrapper for predictions
-- predictions_to_glb: Export predictions to GLB 3D format
-- Colorization and utility functions
-
-Usage:
-    from lingbot_map.vis import PointCloudViewer, viser_wrapper, predictions_to_glb
+Visualization helpers for LingBot-Map.
 
-    # Interactive visualization
-    viewer = PointCloudViewer(pred_dict=predictions, port=8080)
-    viewer.run()
-
-    # Quick visualization
-    viser_wrapper(predictions, port=8080)
-
-    # Export to GLB
-    scene = predictions_to_glb(predictions)
-    scene.export("output.glb")
+This package is imported by the Space only for GLB export. Keep imports lazy so
+optional viewer dependencies like `viser` do not become hard runtime
+requirements for the ZeroGPU Gradio app.
 """
 
-from lingbot_map.vis.point_cloud_viewer import PointCloudViewer
-from lingbot_map.vis.viser_wrapper import viser_wrapper
-from lingbot_map.vis.utils import CameraState, colorize, colorize_np, get_vertical_colorbar
-from lingbot_map.vis.sky_segmentation import (
-    apply_sky_segmentation,
-    download_skyseg_model,
-    load_or_create_sky_masks,
-    segment_sky,
-)
-from lingbot_map.vis.glb_export import predictions_to_glb
+from importlib import import_module
 
 __all__ = [
-    # Main viewer
     "PointCloudViewer",
-    # Quick visualization
     "viser_wrapper",
-    # GLB export
     "predictions_to_glb",
-    # Utilities
     "CameraState",
     "colorize",
     "colorize_np",
     "get_vertical_colorbar",
-    # Sky segmentation
     "apply_sky_segmentation",
     "segment_sky",
     "download_skyseg_model",
     "load_or_create_sky_masks",
 ]
+
+
+def __getattr__(name):
+    if name == "predictions_to_glb":
+        return import_module("lingbot_map.vis.glb_export").predictions_to_glb
+
+    if name in {"apply_sky_segmentation", "segment_sky", "download_skyseg_model", "load_or_create_sky_masks"}:
+        return getattr(import_module("lingbot_map.vis.sky_segmentation"), name)
+
+    if name in {"CameraState", "colorize", "colorize_np", "get_vertical_colorbar"}:
+        return getattr(import_module("lingbot_map.vis.utils"), name)
+
+    if name in {"PointCloudViewer", "viser_wrapper"}:
+        try:
+            module_name = "lingbot_map.vis.point_cloud_viewer" if name == "PointCloudViewer" else "lingbot_map.vis.viser_wrapper"
+            return getattr(import_module(module_name), name)
+        except ModuleNotFoundError as exc:
+            if exc.name == "viser":
+                raise ModuleNotFoundError(
+                    "`viser` is not installed. The Hugging Face Space uses GLB preview instead of the live Viser viewer."
+                ) from exc
+            raise
+
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")