Legends and glyphs

Using custom legends and glyphs within PyVista.

from __future__ import annotations

import pyvista as pv
from pyvista import examples

Default legend for glyphs

The method pyvista.PolyData.add_legend() is able to retrieve and use the glyphs for each plot.

pl = pv.Plotter()

# Loading mesh
mesh = examples.load_random_hills()

# Adding another set of glyphs with opposite value.
mesh["NormalInversed"] = -1 * mesh["Normals"].copy()

# Generating glyph meshes
arrows = mesh.glyph(scale="Normals", orient="Normals", tolerance=0.05)
pl.add_mesh(arrows, color="blue", label="Top pressure")

arrows_inversed = mesh.glyph(scale="NormalInversed", orient="NormalInversed", tolerance=0.05)
pl.add_mesh(arrows_inversed, color="red", label="Lower pressure")

# Adding surface mesh
pl.add_mesh(mesh, scalars="Elevation", cmap="terrain", show_scalar_bar=False)

# Add default legend
pl.add_legend()

# Plot
pl.show()

Using custom legends

You can use specific labels with pyvista.PolyData.add_legend()

pl = pv.Plotter()

# Adding glyph meshes
pl.add_mesh(arrows, color="blue", label="Top pressure")
pl.add_mesh(arrows_inversed, color="red", label="Lower pressure")

# Adding surface mesh
pl.add_mesh(mesh, scalars="Elevation", cmap="terrain", show_scalar_bar=False)

# adding legend
legend = ["New top pressure", "New lower pressure"]

# You can
pl.add_legend(legend)

# In this case, the default values are used, not the ones from the
# :func:`pyvista.PolyData.add_mesh`.

pl.show()

Using custom legend and glyphs

You can use specific labels or glyphs even if they have been specified before.

pl = pv.Plotter()

# Adding glyph meshes
pl.add_mesh(arrows, color="blue", label="Top pressure")
pl.add_mesh(arrows_inversed, color="red", label="Lower pressure")

# Adding surface mesh
pl.add_mesh(mesh, scalars="Elevation", cmap="terrain", show_scalar_bar=False)

# You can use custom glyphs even if they don't match the plot.
# You can use either ``list`` or ``dict`` for passing the data.
legend = [
    ["Top pressure", "blue"],  # no custom glyph
    ["Middle point pressure", "green", "circle"],  # Using a defaults glyph
    {"label": "Lower pressure", "color": "red", "face": pv.Box()},
]

# You can
pl.add_legend(legend)

# Plot
pl.show()