Match labels to corresponding cells in netlist

gplugins/klayout/get_netlist.py

@@ -7,13 +7,16 @@
 
 
 def get_l2n(
-    gdspath: PathType, klayout_tech_path: PathType | None = None
+    gdspath: PathType,
+    klayout_tech_path: PathType | None = None,
+    include_labels: bool = True,
 ) -> kdb.LayoutToNetlist:
     """Get the layout to netlist object from a given GDS and klayout technology file.
 
     Args:
         gdspath: Path to the GDS file.
         klayout_tech_path: Path to the klayout technology file.
+        include_labels: Whether to include labels in the netlist connected as individual nets.
 
     Returns:
         kdb.LayoutToNetlist: The layout to netlist object.
@@ -52,6 +55,8 @@ def get_l2n(
     layer_connection_iter = layer_connection_iter[0] if layer_connection_iter else []
     correct_layer_names = set(sum(layer_connection_iter, ()))
 
+    # label locations on the connected layers on a special layer
+    labels = kdb.Texts(c.begin_shapes_rec(0))
     # define the layers to be extracted
     for l_idx in c.kcl.layer_indexes():
         layer_info = c.kcl.get_info(l_idx)
@@ -61,6 +66,10 @@ def get_l2n(
         except StopIteration:
             same_name_as_in_connections = next(iter(names))
         l2n.connect(l2n.make_layer(l_idx, same_name_as_in_connections))
+        if include_labels:
+            l2n.connect(
+                l2n.make_layer(l_idx, f"{same_name_as_in_connections}_LABELS"), labels
+            )
 
     for layer_a, layer_via, layer_b in (
         (l2n.layer_by_name(layer) for layer in layers)
@@ -73,6 +82,7 @@ def get_l2n(
             l2n.connect(layer_via, layer_b)
 
     l2n.extract_netlist()
+
     return l2n
 
 

gplugins/klayout/plot_nets.py

@@ -1,38 +1,76 @@
 import itertools
-import re
 from pathlib import Path
 
+import klayout.db as kdb
 import matplotlib.pyplot as plt
 import networkx as nx
 
 
+def _get_subcircuit_name(subcircuit: kdb.SubCircuit) -> str:
+    """Get the _cell name_ of a `SubCircuit` instance"""
+    return f"{subcircuit.circuit_ref().name}{subcircuit.expanded_name()}"
+
+
+def netlist_to_networkx(
+    netlist: kdb.Netlist, fully_connected: bool = False, include_labels: bool = True
+) -> nx.Graph:
+    """Convert a KLayout DB `Netlist` to a networkx graph.
+
+    Args:
+        kdbnet: The KLayout DB `Netlist` to convert to a networkx `Graph`.
+        include_labels: Whether to include labels in the graph connected to corresponding cells.
+    """
+    G = nx.Graph()
+    assert netlist.top_circuit_count() == 1, "Multiple top cells not yet supported"
+
+    circuit, *_ = netlist.each_circuit_top_down()
+
+    # first flatten components that won't be kept
+    for subcircuit in circuit.each_subcircuit():
+        if subcircuit.name in {"TODO"}:
+            circuit.flatten_subcircuit(subcircuit)
+
+    for net in circuit.each_net():
+        net_pins = [
+            _get_subcircuit_name(subcircuit_pin_ref.subcircuit())
+            for subcircuit_pin_ref in net.each_subcircuit_pin()
+        ]
+
+        # Assumed lone net with only label info
+        if include_labels and net.expanded_name() and "," not in net.expanded_name():
+            G.add_edges_from(zip(net_pins, [net.name] * len(net_pins)))
+
+        if fully_connected:
+            G.add_edges_from(itertools.combinations(net_pins, 2))
+        else:
+            G.add_edges_from(zip(net_pins[:-1], net_pins[1:]))
+
+    return G
+
+
 def plot_nets(
-    filepath: str | Path, fully_connected: bool = False, interactive: bool = False
+    filepath: str | Path,
+    fully_connected: bool = False,
+    interactive: bool = False,
+    include_labels: bool = True,
 ) -> None:
-    """Plots the connectivity between the components in the GDS file.
+    """Plots the connectivity between the components in the KLayout LayoutToNetlist file from :func:`~get_l2n`.
 
     Args:
-        filepath: Path to the KLayout netlist file.
+        filepath: Path to the KLayout LayoutToNetlist file.
         fully_connected: Whether to plot the graph as elements fully connected to all other ones (True) or
+
             going through other elements (False).
         interactive: Whether to plot an interactive graph with `pyvis` or not.
+        include_labels: Whether to include labels in the graph connected to corresponding cells.
     """
-    filepath = Path(filepath)
-    code = filepath.read_text()
-    names = re.findall(r"name\('([\w,]+)'\)", code)
-
+    l2n = kdb.LayoutToNetlist()
+    l2n.read(str(filepath))
+    netlist = l2n.netlist()
     # Creating a graph for the connectivity
-    G_connectivity = nx.Graph()
-
-    # Adding nodes and edges based on names
-    for name_group in names:
-        individual_names = name_group.split(",")
-        if fully_connected:
-            G_connectivity.add_edges_from(itertools.combinations(individual_names, 2))
-        else:
-            G_connectivity.add_edges_from(
-                zip(individual_names[:-1], individual_names[1:])
-            )
+    G_connectivity = netlist_to_networkx(
+        netlist, fully_connected=fully_connected, include_labels=include_labels
+    )
 
     # Plotting the graph
     if interactive:
@@ -67,10 +105,16 @@ def plot_nets(
     from gdsfactory.samples.demo.lvs import pads_correct, pads_shorted
 
     from gplugins.common.config import PATH
+    from gplugins.klayout.get_netlist import get_l2n
 
     c = pads_correct()
     c = pads_shorted()
     c.show()
 
+    gdspath = c.write_gds(PATH.extra / "pads.gds")
+
+    l2n = get_l2n(gdspath)
     path = PATH.extra / f"{c.name}.txt"
+    l2n.write_l2n(str(path))
+
     plot_nets(path)

gplugins/klayout/tests/test_plot_nets.py

@@ -7,8 +7,9 @@
 from gplugins.klayout.plot_nets import plot_nets
 
 
-@pytest.fixture
-def klayout_netlist(tmp_path):
+@pytest.fixture(scope="session")
+def klayout_netlist(tmp_path) -> str:
+    """Get KLayout netlist file for `pads_correct`. Cached for session scope."""
     c = pads_correct()
 
     gdspath = c.write_gds(gdsdir=tmp_path)
@@ -25,3 +26,11 @@ def test_plot_nets(klayout_netlist):
 def test_plot_nets_interactive(klayout_netlist):
     plot_nets(klayout_netlist, interactive=True)
     assert Path("connectivity.html").exists()
+
+
+def test_plot_nets_not_fully_connected(klayout_netlist):
+    plot_nets(klayout_netlist, fully_connected=False)
+
+
+def test_plot_nets_no_labels(klayout_netlist):
+    plot_nets(klayout_netlist, include_labels=False)