support for multiple gdf and geojson as input

docs/example/input-types.md

@@ -366,6 +366,69 @@ tp.Topology(dict_in, prequantize=False).to_json()
 </div>
 </div>
 
+* * * 
+
+## `list` of GeoDataFrames
+From the package `geopandas` (not a hard dependency).
+
+<div class="code-example mx-1 bg-example">
+<div class="example-label" markdown="1">
+Example 🔧
+{: .label .label-blue-000 }
+</div>
+<div class="example-text" markdown="1">
+
+```python
+import topojson as tp
+import geopandas gpd
+
+gdf_1 = gpd.GeoDataFrame({
+    "uniq_name": ["abc", "def"],
+    "shrd_name": ["rect", "rect"],    
+    "geometry": [
+        geometry.Polygon([[1, 1], [2, 1], [2, 2], [1, 2], [1, 1]]),
+        geometry.Polygon([[0, 1], [1, 1], [1, 2], [0, 2], [0, 1]])          
+    ]
+})
+gdf_2 = gdf_1.dissolve(by='shrd_name', as_index=False)
+
+topo = tp.Topology(data=[gdf_1, gdf_2], object_name=['geom_1', 'geom_2'], prequantize=False)
+topo.to_dict()
+
+```
+
+```python
+{'type': 'Topology',
+ 'objects': {'geom_1': {'geometries': [{'properties': {'uniq_name': 'abc',
+      'shrd_name': 'rect'},
+     'type': 'Polygon',
+     'arcs': [[-1, 2]],
+     'id': 0},
+    {'properties': {'uniq_name': 'def', 'shrd_name': 'rect'},
+     'type': 'Polygon',
+     'arcs': [[1, 0, 3]],
+     'id': 1}],
+   'type': 'GeometryCollection'},
+  'geom_2': {'geometries': [{'properties': {'shrd_name': 'rect',
+      'uniq_name': 'abc'},
+     'type': 'Polygon',
+     'arcs': [[1, 2, 3]],
+     'id': 0}],
+   'type': 'GeometryCollection'}},
+ 'bbox': (0.0, 1.0, 2.0, 2.0),
+ 'arcs': [[[1.0, 2.0], [1.0, 1.0]],
+  [[0.0, 1.0], [0.0, 2.0], [1.0, 2.0]],
+  [[1.0, 2.0], [2.0, 2.0], [2.0, 1.0], [1.0, 1.0]],
+  [[1.0, 1.0], [0.0, 1.0]]]}
+```
+```python
+topo.to_gdf(object_name='geom_2').plot(column='shrd_name')
+topo.to_gdf(object_name='geom_1').plot(column='uniq_name')
+```
+<img src="../images/multiple_objects.png">
+
+</div>
+</div>
 <script>
 window.addEventListener("DOMContentLoaded", event => {
     var opt = {

docs/example/output-types.md

@@ -263,7 +263,8 @@ print(topo.to_json(pretty=True))
 </pre>
 The `pretty` option depends on the setting `indent` and `maxlinelength`, these default to `4` and `88` respectively.
 
-More options in generating the GeoJSON from the computed Topology are `validate` (`True` or `False`), `winding_order` and `decimals`. Where the TopoJSON standard defines a winding order of clock-wise orientation for outer polygons and counter-clockwise orientation for inner polygons is the winding order in the GeoJSON standard the opposite (`CCW_CW`). The `decimals` option defines the number of decimals for the output coordinates.
+More options in generating the GeoJSON from the computed Topology are `validate` (`True` or `False`), `winding_order` and `decimals` and `object_name`. Where the TopoJSON standard defines a winding order of clock-wise orientation for outer polygons and counter-clockwise orientation for inner polygons is the winding order in the GeoJSON standard the opposite (`CCW_CW`). The `decimals` option defines the number of decimals for the output coordinates. With the option `object_name` it is possible to specify which object you want to serialize to GeoJSON (in case of multiple objects in the input data), defaults to index `0`.
+
 </div>
 </div>
 
@@ -299,7 +300,7 @@ topo.to_alt()
 ```
 <div id="embed_output_mesh_altair"></div>
 
-A few more convenience options are included for Altair visualizations, such as assigning a color property for individual features and using geographic projections. 
+A few more convenience options are included for Altair visualizations, such as assigning a color property for individual features and using geographic projections and defining the `object_name`. With the option `object_name` it is possible to specify which object you want to serialize to Altair (in case of multiple objects in the input data), defaults to index `0`. 
 
 Per TopoJSON specification, information of individual features are stored as an nested object within `properties`. For example here is shown the properties of the feature at index-0:
 
@@ -339,7 +340,7 @@ topo.to_alt(color='properties.name:N', projection='equalEarth')
 
 ## .to_gdf()
 
-Serialize the Topology object into a GeoPandas GeoDataFrame. This destroys the Topology. GeoPandas is an optional dependency and not automatically installed. 
+Serialize the Topology object into a GeoPandas GeoDataFrame. This destroys the Topology. GeoPandas is an optional dependency and not automatically installed. With the option `object_name` it is possible to specify which object you want to serialize into a GeoDataFrame using the `object_name` (in case of multiple objects in the input data), defaults to index `0`.
 
 **Note:** There is no winding-order enforcement in the OGR model; so the Fiona/OGR `TopoJSON` driver is NOT used in this routine, but the `.to_geojson()` function.  
 

tests/test_extract.py

@@ -476,3 +476,15 @@ def test_extract_read_geojson_from_json_dict():
     topo = Extract(data).to_dict()
 
     assert len(topo["linestrings"]) == 287
+
+
+def test_extract_read_multiple_gdf_object_name():
+    world = geopandas.read_file(geopandas.datasets.get_path("naturalearth_lowres"))
+    world = world[["continent", "geometry", "pop_est"]]
+    continents = world.dissolve(by="continent", aggfunc="sum")
+
+    topo = Extract(
+        data=[world, continents], options={"object_name": ["world", "continents"]}
+    ).to_dict()
+
+    assert len(topo["objects"]) == len(world) + len(continents)

tests/test_hashmap.py

@@ -30,8 +30,8 @@ def test_hashmap_geomcol_multipolygon_polygon():
     topo = Hashmap(data).to_dict()
 
     assert topo["objects"]["data"]["geometries"][0]["geometries"][0]["arcs"] == [
-        [[4, 0], [1]], 
-        [[2]]
+        [[4, 0], [1]],
+        [[2]],
     ]
 
 
@@ -276,22 +276,36 @@ def test_hashmap_fiona_gpkg_to_dict():
 
     assert len(topo["linestrings"]) == 4
 
+
 # issue #148 and issue #167
 def test_hashmap_serializing_holes():
-    mp = geometry.shape({
-        "type": "MultiPolygon",
-        "coordinates": [
-            [
-                [[0, 0], [20, 0], [10, 20], [0, 0]],  # CCW
-                [[8, 2], [12, 12], [17, 2], [8, 2]],  # CW
-                [[3, 2], [5, 6], [7, 2], [3, 2]],  # CW            
+    mp = geometry.shape(
+        {
+            "type": "MultiPolygon",
+            "coordinates": [
+                [
+                    [[0, 0], [20, 0], [10, 20], [0, 0]],  # CCW
+                    [[8, 2], [12, 12], [17, 2], [8, 2]],  # CW
+                    [[3, 2], [5, 6], [7, 2], [3, 2]],  # CW
+                ],
+                [[[10, 3], [15, 3], [12, 9], [10, 3]]],  # CCW
             ],
-            [[[10, 3], [15, 3], [12, 9], [10, 3]]],  # CCW
-        ]
-    })  
+        }
+    )
     topo = Hashmap(mp)
     topo = topo.to_dict()
 
-    arc = topo['objects']['data']['geometries'][0]['arcs']
+    arc = topo["objects"]["data"]["geometries"][0]["arcs"]
     assert arc == [[[0], [1], [2]], [[3]]]
 
+
+def test_hashmap_read_multiple_gdf_object_name():
+    world = geopandas.read_file(geopandas.datasets.get_path("naturalearth_lowres"))
+    world = world[["continent", "geometry", "pop_est"]]
+    continents = world.dissolve(by="continent", aggfunc="sum")
+
+    topo = Hashmap(
+        data=[world, continents], options={"object_name": ["world", "continents"]}
+    ).to_dict()
+
+    assert len(topo["objects"]) == 2

tests/test_topology.py

@@ -608,6 +608,7 @@ def test_topology_topoquantize():
 
     assert len(topo["arcs"]) == 149
 
+
 # test for https://github.com/mattijn/topojson/issues/164
 def test_topology_gdf_keep_index():
     gdf = (
@@ -619,3 +620,16 @@ def test_topology_gdf_keep_index():
     gdf_idx = topo.to_gdf().index.to_list()
 
     assert gdf_idx == [1, 2, 11, 12, 13]
+
+
+def test_topology_write_multiple_object_json_dict():
+    world = geopandas.read_file(geopandas.datasets.get_path("naturalearth_lowres"))
+    world = world[["continent", "geometry", "pop_est"]]
+    continents = world.dissolve(by="continent", aggfunc="sum")
+
+    topo = topojson.Topology(
+        data=[world, continents], object_name=["world", "continents"]
+    )
+    topo_dict = topo.to_dict()
+
+    assert len(topo_dict["objects"]) == 2

topojson/core/cut.py

@@ -1,9 +1,11 @@
 import itertools
 import pprint
 import copy
+import warnings
 import numpy as np
 from shapely import geometry
 from shapely.strtree import STRtree
+from shapely.errors import ShapelyDeprecationWarning
 from .join import Join
 from ..ops import insert_coords_in_line
 from ..ops import np_array_bbox_points_line
@@ -109,7 +111,9 @@ def _cutter(self, data):
                 mp = geometry.MultiPoint([mp])
 
             # create spatial index on junctions
-            tree_splitter = STRtree(mp)
+            with warnings.catch_warnings():
+                warnings.filterwarnings("ignore", category=ShapelyDeprecationWarning)
+                tree_splitter = STRtree(mp)
             slist = []
             # junctions are only existing in coordinates of linestring
             if self.options.shared_coords:

topojson/core/extract.py

@@ -60,6 +60,8 @@ def __init__(self, data, options={}):
         self._is_single = True
         self._invalid_geoms = 0
         self._tried_geojson = False
+        self._is_multi_geom = False
+        self._geom_offset = 0
 
         self.output = self._extractor(data)
 
@@ -165,6 +167,7 @@ def _serialize_geom_type(self, geom):
         - geopandas.GeoSeries
         - dict of objects that provide a __geo_interface__
         - list of objects that provide a __geo_interface__
+        - list of geopandas.GeoDataFrames
         - object that provide a __geo_interface__
         - TopoJSON dict
         - TopoJSON string
@@ -574,8 +577,32 @@ def _extract_list(self, geom):
         geom : list
             List instance
         """
-        # convert list to indexed-dictionary
-        data = dict(enumerate(geom))
+        # check if there are multiple entries in the `object_name` in settings.
+        # currently only supports multiple GeoDataFrames as input entries
+        if len(self.options.object_name) > 1:
+            # list consist of objects
+            if len(self.options.object_name) != len(geom):
+                raise LookupError(
+                    "the number of data objects does not match the number of object_name"
+                )
+            geom_offset = np.cumsum([len(gdf) for gdf in geom]).tolist()
+            geom_offset.pop()
+            geom_offset.insert(0, 0)
+            self._geom_offset = geom_offset
+            for ix, gdf in enumerate(geom):
+                gdf = gdf.copy()
+                start = geom_offset[ix]
+                gdf["__geom_name"] = self.options.object_name[ix]
+                geom[ix] = dict(enumerate(gdf.to_dict(orient="records"), start))
+
+            for ix in range(1, len(geom)):
+                geom[0].update(geom.pop(ix))
+            data = geom[0]
+            self._is_multi_geom = True
+        else:
+            # list consist of features
+            # convert list to indexed-dictionary
+            data = dict(enumerate(geom))
 
         # new data dictionary is created, throw the geometries back to main()
         self._is_single = False

topojson/core/hashmap.py

@@ -92,22 +92,36 @@ def _hashmapper(self, data):
         # resolve bookkeeping of coordinates in objects, including delta-encoding
         list(self._resolve_objects(["arcs", "coordinates"], self._data["objects"]))
 
-        objects = {}
-        objects["geometries"] = []
-        objects["type"] = "GeometryCollection"
-        for feature in data["objects"]:
-            feat = data["objects"][feature]
-            feat["id"] = feature
-
-            if "geometries" in feat and len(feat["geometries"]) == 1:
-                feat["type"] = feat["geometries"][0]["type"]
+        resolved_data_objects = {}
+        for object_ix, object_name in enumerate(self.options.object_name):
+            objects = {}
+            objects["geometries"] = []
+            objects["type"] = "GeometryCollection"
+            for feature in data["objects"]:
+                feat = data["objects"][feature]
+                if not self._is_multi_geom:
+                    do_resolve = True
+                    feat["id"] = feature
+                elif (
+                    "__geom_name" in feat["properties"]
+                    and feat["properties"]["__geom_name"] == object_name
+                ):
+                    do_resolve = True
+                    feat["id"] = feature - self._geom_offset[object_ix]
+                    del feat["properties"]["__geom_name"]
+                else:
+                    do_resolve = False
 
-            self._resolve_arcs(feat)
+                if do_resolve:
+                    if "geometries" in feat and len(feat["geometries"]) == 1:
+                        feat["type"] = feat["geometries"][0]["type"]
 
-            objects["geometries"].append(feat)
+                    self._resolve_arcs(feat)
 
+                    objects["geometries"].append(feat)
+            resolved_data_objects[object_name] = objects
         data["objects"] = {}
-        data["objects"][self.options.object_name] = objects
+        data["objects"] = resolved_data_objects
 
         # prepare to return object
         data = self._data

topojson/core/join.py

@@ -6,7 +6,6 @@
 from shapely.wkb import loads
 from shapely.ops import shared_paths
 from shapely.ops import linemerge
-from shapely import speedups
 from ..ops import select_unique_combs
 from ..ops import simplify
 from ..ops import quantize
@@ -15,9 +14,6 @@
 from ..utils import serialize_as_svg
 from .extract import Extract
 
-if speedups.available:
-    speedups.enable()
-
 
 class Join(Extract):
     """