Fix/node-numbering (#3297)

* tests: add test

* tests: testing

* fix: removing everything that handled the duplicated points. It is not needed anymore.

* chore: adding changelog file 3297.fixed.md

---------

Co-authored-by: pyansys-ci-bot <92810346+pyansys-ci-bot@users.noreply.github.com>

doc/changelog.d/3297.fixed.md

@@ -0,0 +1 @@
+Fix/node-numbering

src/ansys/mapdl/core/mapdl_extended.py

@@ -1243,6 +1243,7 @@ def eplot(self, show_node_numbering=False, vtk=None, **kwargs):
 
             pl = kwargs.get("plotter", None)
             pl = MapdlPlotter().switch_scene(pl)
+            pl.mapdl = self
 
             kwargs.setdefault("title", "MAPDL Element Plot")
             if not self._mesh.n_elem:

src/ansys/mapdl/core/plotting/visualizer.py

@@ -30,7 +30,7 @@
 from numpy.typing import NDArray
 
 from ansys.mapdl.core import _HAS_PYVISTA
-from ansys.mapdl.core.misc import get_bounding_box, unique_rows
+from ansys.mapdl.core.misc import get_bounding_box
 from ansys.mapdl.core.plotting.consts import (
     ALLOWED_TARGETS,
     BC_D,
@@ -424,16 +424,12 @@ def add_mesh(
                 )
 
         for label in labels:
-            # verify points are not duplicates
-            points = np.atleast_2d(np.array(label["points"]))
-            _, idx, idx2 = unique_rows(points)
-            points = points[idx2][idx]  # Getting back the initial order.
+            # Pyvista does not support plotting two labels with the same point.
+            # It does handle that case by keeping only the first label.
 
-            # Converting python order (0 based)
-            labels_ = np.array(label["labels"] - 1)[idx]
             self.add_labels(
-                points,
-                labels_,
+                label["points"],
+                label["labels"],
                 show_points=False,
                 shadow=False,
                 font_size=font_size,

tests/test_plotting.py

@@ -1109,3 +1109,20 @@ def test_node_numbering_order(mapdl, cleared):
     # There is no way to retrieve labels from the plotter object. So we cannot
     # test it.
     pl.show()
+
+
+def test_lplot_line(mapdl, cleared):
+    mapdl.prep7()
+
+    # Create keypoints 3 keypoints
+    mapdl.k(1, 0, 0, 0)
+    mapdl.k(2, 1, 0, 0)
+    mapdl.k(3, 1, 1, 0)
+
+    # Create line connecting keypoints 1 and 2
+    mapdl.l(1, 2)
+
+    # Plot the geometry
+    mapdl.lplot(
+        show_line_numbering=False, show_keypoint_numbering=True, color_lines=True
+    )