Rework Line2D

ksunden · ksunden · commit a832384cf825 · 2026-01-08T13:57:43.000-06:00
diff --git a/lib/matplotlib/lines.py b/lib/matplotlib/lines.py
@@ -4,6 +4,7 @@
 
 import copy
 
+from dataclasses import dataclass
 from numbers import Integral, Number, Real
 import logging
 
@@ -18,7 +19,8 @@
 from .path import Path
 from .transforms import Bbox, BboxTransformTo, TransformedPath
 from ._enums import JoinStyle, CapStyle
-from ._data_containers._helpers import containerize_draw
+from ._data_containers._helpers import containerize_draw, _get_graph, check_container
+from ._data_containers.description import Desc
 
 # Imported here for backward compatibility, even though they don't
 # really belong.
@@ -228,6 +230,26 @@ def _slice_or_none(in_v, slc):
         raise ValueError(f"markevery={markevery!r} is not a recognized value")
 
 
+@dataclass
+class LineContainer:
+    x: np.ndarray
+    y: np.ndarray
+
+    def describe(self):
+
+        return {
+            "x": Desc(("N",), "data"),
+            "y": Desc(("N",), "data"),
+        }
+
+    def query(self, graph, parent_coordinates="axes"):
+        return {
+            "x": self.x,
+            "y": self.y,
+        }, ""
+        # TODO hash
+
+
 @_docstring.interpd
 @_api.define_aliases({
     "antialiased": ["aa"],
@@ -336,6 +358,9 @@ def __init__(self, xdata, ydata, *,
         """
         super().__init__()
 
+        self._container = self._init_container()
+        self.__query = None
+
         # Convert sequences to NumPy arrays.
         if not np.iterable(xdata):
             raise RuntimeError('xdata must be a sequence')
@@ -414,21 +439,60 @@ def __init__(self, xdata, ydata, *,
                 not isinstance(self._picker, bool)):
             self._pickradius = self._picker
 
-        self._xorig = np.asarray([])
-        self._yorig = np.asarray([])
         self._invalidx = True
         self._invalidy = True
-        self._x = None
-        self._y = None
-        self._xy = None
         self._path = None
         self._transformed_path = None
         self._subslice = False
         self._x_filled = None  # used in subslicing; only x is needed
-        self._container = None
 
         self.set_data(xdata, ydata)
 
+    def set_container(self, container):
+        self._container = container
+        self.stale = True
+
+    def get_container(self):
+        return self._container
+
+    def _init_container(self):
+        return LineContainer(
+            x=np.array([]),
+            y=np.array([]),
+        )
+
+    @property
+    def _xorig(self):
+        return self._query["x"]
+
+    @property
+    def _x(self):
+        xconv = self.convert_xunits(self._xorig)
+        return _to_unmasked_float_array(xconv).ravel()
+
+    @property
+    def _yorig(self):
+        return self._query["y"]
+
+    @property
+    def _y(self):
+        yconv = self.convert_yunits(self._yorig)
+        return _to_unmasked_float_array(yconv).ravel()
+
+    @property
+    def _xy(self):
+        x, y = self._x, self._y
+        return np.column_stack(np.broadcast_arrays(x, y)).astype(float)
+
+    @property
+    def _query(self):
+        if self.__query is not None:
+            return self.__query
+        return self._container.query(_get_graph(self.axes))[0]
+
+    def _cache_query(self):
+        self.__query = self._container.query(_get_graph(self.axes))[0]
+
     def contains(self, mouseevent):
         """
         Test whether *mouseevent* occurred on the line.
@@ -685,9 +749,6 @@ def recache(self, always=False):
         else:
             y = self._y
 
-        self._xy = np.column_stack(np.broadcast_arrays(x, y)).astype(float)
-        self._x, self._y = self._xy.T  # views
-
         self._subslice = False
         if (self.axes
                 and len(x) > self._subslice_optim_min_size
@@ -753,6 +814,8 @@ def draw(self, renderer, *, graph=None):
         if not self.get_visible():
             return
 
+        self._cache_query()
+
         if self._invalidy or self._invalidx:
             self.recache()
         self.ind_offset = 0  # Needed for contains() method.
@@ -1300,9 +1363,11 @@ def set_xdata(self, x):
         set_data
         set_ydata
         """
+        check_container(self, LineContainer, "'set_xdata'")
         if not np.iterable(x):
             raise RuntimeError('x must be a sequence')
-        self._xorig = copy.copy(x)
+        self._container.x = copy.copy(x)
+        self.__query = None
         self._invalidx = True
         self.stale = True
 
@@ -1319,9 +1384,11 @@ def set_ydata(self, y):
         set_data
         set_xdata
         """
+        check_container(self, LineContainer, "'set_ydata'")
         if not np.iterable(y):
             raise RuntimeError('y must be a sequence')
-        self._yorig = copy.copy(y)
+        self._container.y = copy.copy(y)
+        self.__query = None
         self._invalidy = True
         self.stale = True
 
