better plane init in python

docs/snippets/all/views/spatial3d.py

@@ -27,7 +27,7 @@
             visible=True,  # The grid is enabled by default, but you can hide it with this property.
             spacing=0.1,  # Makes the grid more fine-grained.
             # By default, the plane is inferred from view coordinates setup, but you can set arbitrary planes.
-            plane=rr.components.Plane3D((0, 0, 1), -5.0),
+            plane=rr.components.Plane3D.XY.with_distance(-5.0),
             stroke_width=2.0,  # Makes the grid lines twice as thick as usual.
             color=[255, 255, 255, 128],  # Colors the grid a half-transparent white.
         ),

rerun_py/rerun_sdk/rerun/datatypes/plane3d_ext.py

@@ -1,8 +1,9 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any, Union
+from typing import TYPE_CHECKING, Any, Union, cast
 
 import numpy as np
+import numpy.typing as npt
 import pyarrow as pa
 
 from .._validators import flat_np_float32_array_from_array_like
@@ -53,6 +54,20 @@ def __init__(self: Any, normal: Vec3DLike, distance: Union[float, int, None] = N
 
         self.__attrs_init__(xyzd=np.concatenate((normal_np, distance_np)))
 
+    def normal(self: Any) -> npt.NDArray[np.float32]:
+        """Returns the normal vector of the plane."""
+        return cast(npt.NDArray[np.float32], self.xyzd[:3])
+
+    def distance(self: Any) -> float:
+        """Returns the distance of the plane from the origin."""
+        return cast(float, self.xyzd[3])
+
+    def with_distance(self: Any, distance: float) -> Plane3D:
+        """Returns a new plane with the same normal but with the distance set to the given amount."""
+        from . import Plane3D
+
+        return Plane3D(self.normal(), distance)
+
     @staticmethod
     def native_to_pa_array_override(data: Plane3DArrayLike, data_type: pa.DataType) -> pa.Array:
         planes = flat_np_float32_array_from_array_like(data, 4)