fix(plotting): Improve interface of the plotting class. (#3702)

* fix(plotting): Test plotting changes

* chore: adding changelog file 3702.fixed.md [dependabot-skip]

* fix(plotting): Small bug

* fix: Bug caused tests failure

* fix: Add warning

* chore: adding changelog file 3702.fixed.md [dependabot-skip]

* test: Add mesh testing

* test: Add docstring to test

* fix: PyVista lazy import

---------

Co-authored-by: pyansys-ci-bot <92810346+pyansys-ci-bot@users.noreply.github.com>
Co-authored-by: Camille <78221213+clatapie@users.noreply.github.com>
Co-authored-by: German <28149841+germa89@users.noreply.github.com>

Author: 4 people

doc/changelog.d/3702.fixed.md

@@ -0,0 +1 @@
+fix(plotting): Improve interface of the plotting class.

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

@@ -22,13 +22,14 @@
 
 """Module for the MapdlPlotter class."""
 from collections import OrderedDict
-from typing import Any, Iterable, Optional, Union
+from typing import Any, Dict, Iterable, Optional, Union
 
 from ansys.tools.visualization_interface import Plotter
 from ansys.tools.visualization_interface.backends.pyvista import PyVistaBackendInterface
 import numpy as np
 from numpy.typing import NDArray
 
+from ansys.mapdl.core import LOG as logger
 from ansys.mapdl.core import _HAS_VISUALIZER
 from ansys.mapdl.core.misc import get_bounding_box
 from ansys.mapdl.core.plotting.consts import (
@@ -277,9 +278,9 @@ def plot_iter(
 
     def add_mesh(
         self,
-        meshes,
-        points,
-        labels,
+        meshes: Union[pv.PolyData, Dict[str, Any]] = [],
+        points=[],
+        labels=[],
         *,
         cpos=None,
         show_bounds=False,
@@ -328,6 +329,10 @@ def add_mesh(
         plotter_kwargs : dict, optional
             Extra kwargs, by default {}
         """
+        if not meshes and not points and not labels:
+            logger.warning("No meshes, points or labels to plot.")
+            return
+
         if theme is None:
             theme = MapdlTheme()
 
@@ -375,31 +380,43 @@ def add_mesh(
                 **(add_points_kwargs or {}),
             )
 
+        if isinstance(meshes, pv.PolyData):
+            meshes = [meshes]
         for mesh in meshes:
-            scalars: Optional[NDArray[Any]] = mesh.get("scalars")
-
-            if (
-                "scalars" in mesh
-                and scalars.ndim == 2
-                and (scalars.shape[1] == 3 or scalars.shape[1] == 4)
-            ):
-                # for the case we are using scalars for plotting
-                rgb = True
+            rgb = False
+            if isinstance(mesh, Dict):
+                scalars: Optional[NDArray[Any]] = mesh.get("scalars")
+
+                if (
+                    "scalars" in mesh
+                    and scalars.ndim == 2
+                    and (scalars.shape[1] == 3 or scalars.shape[1] == 4)
+                ):
+                    # for the case we are using scalars for plotting
+                    rgb = True
+
+                # To avoid index error.
+                mesh_ = mesh["mesh"]
+                if not isinstance(mesh_, list):
+                    mesh_ = [mesh_]
             else:
-                rgb = False
-
-            # To avoid index error.
-            mesh_ = mesh["mesh"]
-            if not isinstance(mesh_, list):
-                mesh_ = [mesh_]
-
+                scalars = None
+                mesh_ = meshes
             for each_mesh in mesh_:
                 self.scene.add_mesh(
                     each_mesh,
                     scalars=scalars,
                     scalar_bar_args=scalar_bar_args,
-                    color=mesh.get("color", color),
-                    style=mesh.get("style", style),
+                    color=(
+                        mesh.get("color", color)
+                        if isinstance(mesh, Dict) and "color" in mesh
+                        else color
+                    ),
+                    style=(
+                        mesh.get("style", style)
+                        if isinstance(mesh, Dict) and "style" in mesh
+                        else style
+                    ),
                     show_edges=show_edges,
                     edge_color=edge_color,
                     smooth_shading=smooth_shading,
@@ -648,9 +665,9 @@ def bc_nodes_plot(
 
     def plot(
         self,
-        meshes,
-        points,
-        labels,
+        meshes: Union[pv.PolyData, Dict[str, Any]] = [],
+        points=[],
+        labels=[],
         *,
         title="",
         cpos=None,

tests/test_plotting.py

@@ -1262,6 +1262,37 @@ def test_plot_path(mapdl, tmpdir):
         mapdl.eplot(vtk=False)
 
 
+def test_add_mesh():
+    """Test the add_mesh method from MapdlPlotter class."""
+    import pyvista as pv
+
+    cube1 = pv.Cube()
+    pl1 = MapdlPlotter()
+    pl1.add_mesh(cube1)
+
+    cube2 = pv.Cube()
+    meshes_dict = [
+        {
+            "mesh": cube2,
+            "scalars": np.random.default_rng(seed=1).random((8, 3)),
+        }
+    ]
+
+    pl2 = MapdlPlotter()
+    pl2.add_mesh(meshes_dict)
+
+    cube3 = pv.Cube()
+    sphere = pv.Sphere()
+
+    pl3 = MapdlPlotter()
+    pl3.add_mesh([cube3, sphere])
+
+    assert pl1.meshes[0] == cube1
+    assert pl2.meshes[0] == cube2
+    assert pl3.meshes[0] == cube3
+    assert pl3.meshes[1] == sphere
+
+
 def test_plot_path_screenshoot(mapdl, cleared, tmpdir):
     mapdl.graphics("POWER")
     # mapdl.screenshot is not affected by the device.