feat: new "--no_normals" option to not include normals in 3D tiles (#159

)

* Added new "--no_normals" option to not include normals in 3D tiles

* Updated tests

py3dtilers/Common/README.md

@@ -178,6 +178,24 @@ Project the features on another CRS. The `crs_in` flag allows to specify the inp
 <tiler> <input> --crs_in EPSG:3946 --crs_out EPSG:4171
 ```
 
+### No Normals
+
+| Tiler        |                    |
+| ------------ | ------------------ |
+| CityTiler    | :heavy_check_mark: |
+| ObjTiler     | :heavy_check_mark: |
+| GeojsonTiler | :heavy_check_mark: |
+| IfcTiler     | :heavy_check_mark: |
+| TilesetTiler | :heavy_check_mark: |
+
+Optionally disable creation of normals in 3D tiles:
+
+```bash
+<tiler> <input> --no_normals
+```
+
+This could be very useful for 3D tiles created out Photogrammetry OBJ meshes. If normals are not present, Cesium wil display tiles using flat lighning. 
+
 ### With texture
 
 | Tiler        |                    |

py3dtilers/Common/tiler.py

@@ -67,6 +67,11 @@ def __init__(self):
                                  dest='with_texture',
                                  action='store_true',
                                  help='Adds texture to 3DTiles when defined')
+
+        self.parser.add_argument('--no_normals',
+                                 dest='no_normals',
+                                 action='store_true',
+                                 help='If specified, no normals will be written to glTf, useful for Photogrammetry meshes')
 
         self.parser.add_argument('--quality',
                                  nargs='?',
@@ -244,11 +249,12 @@ def create_tileset_from_groups(self, groups: Groups, extension_name=None):
         """
         create_loa = self.args.loa is not None
         geometric_errors = self.args.geometric_error if hasattr(self.args, 'geometric_error') else [None, None, None]
+        with_normals = False if self.args.no_normals else True
 
         tree = LodTree(groups, self.args.lod1, create_loa, self.args.with_texture, geometric_errors, self.args.texture_lods)
 
         self.create_output_directory()
-        return FromGeometryTreeToTileset.convert_to_tileset(tree, self.args, extension_name, self.get_output_dir())
+        return FromGeometryTreeToTileset.convert_to_tileset(tree, self.args, extension_name, self.get_output_dir(), with_normals=with_normals)
 
     def create_output_directory(self):
         """

py3dtilers/Common/tileset_creation.py

@@ -19,7 +19,7 @@ class FromGeometryTreeToTileset():
     nb_nodes = 0
 
     @staticmethod
-    def convert_to_tileset(geometry_tree: 'GeometryTree', user_arguments=None, extension_name=None, output_dir=None):
+    def convert_to_tileset(geometry_tree: 'GeometryTree', user_arguments=None, extension_name=None, output_dir=None, with_normals=True):
         """
         Recursively creates a tileset from the nodes of a GeometryTree
         :param geometry_tree: an instance of GeometryTree to transform into 3DTiles.
@@ -39,7 +39,7 @@ def convert_to_tileset(geometry_tree: 'GeometryTree', user_arguments=None, exten
             root_node = geometry_tree.root_nodes[0]
             root_node.set_node_features_geometry(user_arguments)
             offset = FromGeometryTreeToTileset.__transform_node(root_node, user_arguments, tree_centroid, obj_writer=obj_writer)
-            tileset.add_tile(FromGeometryTreeToTileset.__create_tile(root_node, offset, extension_name, output_dir))
+            tileset.add_tile(FromGeometryTreeToTileset.__create_tile(root_node, offset, extension_name, output_dir, with_normals))
             geometry_tree.root_nodes.remove(root_node)
 
         if user_arguments.obj is not None:
@@ -84,7 +84,7 @@ def __transform_node(node: 'GeometryNode', user_args, tree_centroid=np.array([0,
         return distance if user_args.offset[0] == 'centroid' else offset
 
     @staticmethod
-    def __create_tile(node: 'GeometryNode', transform_offset, extension_name=None, output_dir=None):
+    def __create_tile(node: 'GeometryNode', transform_offset, extension_name=None, output_dir=None, with_normals=True):
         """
         Create a tile from a node. Recursively create tiles from the children of the node.
         :param node: the GeometryNode.
@@ -98,7 +98,7 @@ def __create_tile(node: 'GeometryNode', transform_offset, extension_name=None, o
         tile = Tile()
         tile.set_geometric_error(node.geometric_error)
 
-        content_b3dm = FromGeometryTreeToTileset.__create_tile_content(feature_list, extension_name, node.has_texture(), node.downsample_factor)
+        content_b3dm = FromGeometryTreeToTileset.__create_tile_content(feature_list, extension_name, node.has_texture(), node.downsample_factor, with_normals)
         tile.set_content(content_b3dm)
         tile.set_content_uri('tiles/' + f'{FromGeometryTreeToTileset.tile_index}.b3dm')
         tile.write_content(output_dir)
@@ -125,12 +125,12 @@ def __create_tile(node: 'GeometryNode', transform_offset, extension_name=None, o
 
         FromGeometryTreeToTileset.tile_index += 1
         for child_node in node.child_nodes:
-            tile.add_child(FromGeometryTreeToTileset.__create_tile(child_node, [0., 0., 0.], extension_name, output_dir))
+            tile.add_child(FromGeometryTreeToTileset.__create_tile(child_node, [0., 0., 0.], extension_name, output_dir, with_normals))
 
         return tile
 
     @staticmethod
-    def __create_tile_content(feature_list: 'FeatureList', extension_name=None, with_texture=False, downsample_factor=1):
+    def __create_tile_content(feature_list: 'FeatureList', extension_name=None, with_texture=False, downsample_factor=1, with_normals=True):
         """
         :param pre_tile: an array containing features of a single tile
 
@@ -174,7 +174,7 @@ def __create_tile_content(feature_list: 'FeatureList', extension_name=None, with
                               0, 1, 0, 0,
                               0, 0, 0, 1])
 
-        gltf = GlTF.from_binary_arrays(arrays, transform, materials=materials)
+        gltf = GlTF.from_binary_arrays(arrays, transform, materials=materials, withNormals=with_normals)
 
         # Create a batch table and add the ID of each feature to it
         ids = [feature.get_id() for feature in feature_list]

tests/test_cityTemporalTiler.py

@@ -22,7 +22,7 @@ def get_default_namespace():
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, scale=1,
                      output_dir=None, geometric_error=[None, None, None],
                      split_surfaces=False, add_color=False, kd_tree_max=None, texture_lods=0,
-                     keep_ids=[], exclude_ids=[])
+                     keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 class Test_Tile(unittest.TestCase):

tests/test_cityTiler.py

@@ -18,7 +18,7 @@ def get_default_namespace():
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, scale=1,
                      output_dir=None, geometric_error=[None, None, None],
                      split_surfaces=False, add_color=False, kd_tree_max=None, ids=[], texture_lods=0,
-                     keep_ids=[], exclude_ids=[])
+                     keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 class Test_Tile(unittest.TestCase):

tests/test_geojsonTiler.py

@@ -9,7 +9,7 @@ def get_default_namespace():
     return Namespace(obj=None, loa=None, lod1=False, crs_in='EPSG:3946',
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, scale=1,
                      output_dir=None, geometric_error=[None, None, None], kd_tree_max=None,
-                     texture_lods=0, keep_ids=[], exclude_ids=[])
+                     texture_lods=0, keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 class Test_Tile(unittest.TestCase):

tests/test_ifcTiler.py

@@ -8,7 +8,7 @@
 def get_default_namespace():
     return Namespace(obj=None, loa=None, lod1=False, crs_in='EPSG:3946',
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, grouped_by='IfcTypeObject', scale=1,
-                     output_dir=None, geometric_error=[None, None, None], kd_tree_max=None, texture_lods=0, keep_ids=[], exclude_ids=[])
+                     output_dir=None, geometric_error=[None, None, None], kd_tree_max=None, texture_lods=0, keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 class Test_Tile(unittest.TestCase):

tests/test_objTiler.py

@@ -9,7 +9,7 @@ def get_default_namespace():
     return Namespace(obj=None, loa=None, lod1=False, crs_in='EPSG:3946',
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, scale=1,
                      output_dir=None, geometric_error=[None, None, None], kd_tree_max=None,
-                     texture_lods=0, keep_ids=[], exclude_ids=[])
+                     texture_lods=0, keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 class Test_Tile(unittest.TestCase):
@@ -24,6 +24,17 @@ def test_basic_case(self):
         if tileset is not None:
             tileset.write_as_json(Path(obj_tiler.args.output_dir))
 
+    def test_basic_case_no_normals(self):
+        obj_tiler = ObjTiler()
+        obj_tiler.files = [Path('tests/obj_tiler_data/Cube/cube_1.obj'), Path('tests/obj_tiler_data/Cube/cube_2.obj')]
+        obj_tiler.args = get_default_namespace()
+        obj_tiler.args.output_dir = Path("tests/obj_tiler_data/generated_tilesets/basic_case_no_normals")
+        obj_tiler.args.no_normals = True
+
+        tileset = obj_tiler.from_obj_directory()
+        if tileset is not None:
+            tileset.write_as_json(Path(obj_tiler.args.output_dir))
+
     def test_texture(self):
         obj_tiler = ObjTiler()
         obj_tiler.files = [Path('tests/obj_tiler_data/TexturedCube/cube.obj')]

tests/test_tiler.py

@@ -12,7 +12,7 @@ def get_default_namespace():
     return Namespace(obj=None, loa=None, lod1=False, crs_in='EPSG:3946',
                      crs_out='EPSG:3946', offset=[0, 0, 0], with_texture=False, scale=1,
                      output_dir=None, geometric_error=[None, None, None], kd_tree_max=None,
-                     texture_lods=0, keep_ids=[], exclude_ids=[])
+                     texture_lods=0, keep_ids=[], exclude_ids=[], no_normals=False)
 
 
 triangles = [[np.array([1843366, 5174473, 200]),