"""
.. _vertices_example:

Visible Vertices
~~~~~~~~~~~~~~~~

Display vertices on a mesh in the same fashion as edge visibility.
"""

# sphinx_gallery_thumbnail_number = 3
import pyvista as pv
from pyvista import examples

mesh = examples.download_bunny_coarse()

cpos = pv.CameraPosition(
    position=(0.036, 0.367, 0.884),
    focal_point=(0.024, 0.033, -0.022),
    viewup=(-0.303, 0.895, -0.325),
)

# %%
# We can easily display all vertices of a mesh with a ``points`` style
# representation when plotting:
pl = pv.Plotter()
pl.add_mesh(
    mesh, style='points', color='magenta', render_points_as_spheres=True, point_size=10
)
pl.show(cpos=cpos)


# %%
# However, we often want to see the vertices of a mesh rendered atop the
# surface geometry. Much like how we can render the edges of a mesh:
pl = pv.Plotter()
pl.add_mesh(mesh, show_edges=True)
pl.show(cpos=cpos)


# %%
# In order to display the vertices atop a mesh's surface geometry, simply pass
# ``show_vertices=True`` to render them along side the original geometry.
#
# .. note::
#    Vertex styling can be changed using ``vertex_color``, ``vertex_opacity``,
#    and ``vertex_style``.
pl = pv.Plotter()
pl.add_mesh(
    mesh,
    show_edges=True,
    vertex_color='magenta',
    render_points_as_spheres=True,
    point_size=10,
    show_vertices=True,
)
pl.show(cpos=cpos)


# %%
# If you wish to have further control over the way surface points are plotted
# alongside the surface geometry, extract the surface points and plot them
# separately.
#
# The first step is to extract the outer surface geometry of the mesh then
# grab all the points of that extraction.
surf_points = mesh.extract_surface(algorithm=None).points


# %%
# Now that we have the vertices extracted, we can use :func:`add_points()
# <pyvista.Plotter.add_points>` to render them along side the original
# geometry.
#
# Color the points by their Y position.

pl = pv.Plotter()
pl.add_mesh(mesh, show_edges=True)
pl.add_points(
    surf_points,
    color='magenta',
    render_points_as_spheres=True,
    point_size=10,
    scalars=surf_points[:, 1],
    lighting=False,
    show_scalar_bar=False,
)
pl.show(cpos=cpos)
# %%
# .. tags:: plot
