properly render point-like objects in viz

CHANGELOG.md

@@ -5,9 +5,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-# Changed
+### Added
+
+### Changed
 - Source validation happens before simulation upload and raises an error if no source is present.
 
+### Fixed
+- Point-like objects correctly appear as single points using `plt.scatter`.
+
 ## [2.3.0] - 2023-6-30
 
 ### Added

tests/test_components/test_viz.py

@@ -1,9 +1,35 @@
 """Tests visualization operations."""
 import pytest
+import matplotlib.pylab as plt
 import tidy3d as td
 from tidy3d.components.viz import Polygon
 
 
 def test_make_polygon_dict():
     p = Polygon(context={"coordinates": [(1, 0), (0, 1), (0, 0)]})
     p.interiors
+
+
+@pytest.mark.parametrize("center_z, len_collections", ((0, 1), (0.1, 0)))
+def test_0d_plot(center_z, len_collections):
+    """Ensure that 0d objects show up in plots."""
+
+    sim = td.Simulation(
+        size=(1, 1, 1),
+        sources=[
+            td.PointDipole(
+                center=(0, 0, center_z),
+                source_time=td.GaussianPulse(
+                    freq0=td.C_0 / 1.0,
+                    fwidth=td.C_0 / 5.0,
+                ),
+                polarization="Ez",
+            )
+        ],
+        run_time=1e-13,
+    )
+
+    ax = sim.plot(z=0)
+
+    # if a point is plotted, a single collection will be present, otherwise nothing
+    assert len(ax.collections) == len_collections

tidy3d/components/geometry.py

@@ -427,6 +427,8 @@ def plot_shape(self, shape: Shapely, plot_params: PlotParams, ax: Ax) -> Ax:
         if isinstance(_shape, LineString):
             xs, ys = zip(*_shape.coords)
             ax.plot(xs, ys, color=plot_params.edgecolor)
+        elif isinstance(_shape, Point):
+            ax.scatter(shape.x, shape.y, color=plot_params.facecolor)
         else:
             patch = polygon_patch(_shape, **plot_params.to_kwargs())
             ax.add_artist(patch)
@@ -1275,6 +1277,7 @@ def surfaces_with_exclusion(
             surfaces = [surf for surf in surfaces if surf.name[-2:] not in exclude_surfaces]
         return surfaces
 
+    # pylint:disable=too-many-locals
     def intersections_plane(self, x: float = None, y: float = None, z: float = None):
         """Returns shapely geometry at plane specified by one non None value of x,y,z.
 
@@ -1302,7 +1305,17 @@ def intersections_plane(self, x: float = None, y: float = None, z: float = None)
         dz = np.abs(z0 - position)
         if dz > Lz / 2 + fp_eps:
             return []
-        return [box(minx=x0 - Lx / 2, miny=y0 - Ly / 2, maxx=x0 + Lx / 2, maxy=y0 + Ly / 2)]
+
+        minx = x0 - Lx / 2
+        miny = y0 - Ly / 2
+        maxx = x0 + Lx / 2
+        maxy = y0 + Ly / 2
+
+        # handle case where the box vertices are identical
+        if isclose(minx, maxx) and isclose(miny, maxy):
+            return [Point(minx, miny)]
+
+        return [box(minx=minx, miny=miny, maxx=maxx, maxy=maxy)]
 
     def inside(
         self, x: np.ndarray[float], y: np.ndarray[float], z: np.ndarray[float]