Simple 3D Mesh Plot

Mix.install([
  {:plotly_ex, "~> 0.3"},
  {:kino, "~> 0.18"}
])

Section

Mesh3d.new(x:, y:, z:, alphahull: N) constructs a mesh from a point cloud using the alpha-hull algorithm. alphahull: 5 gives a moderate hull — larger values produce a looser (more convex) hull; alphahull: 0 uses the convex hull. color: and opacity: style the mesh.

alias Plotly.{Figure, Mesh3d}

# Random point cloud on a sphere surface
n = 100

{xs, ys, zs} =
  Enum.reduce(1..n, {[], [], []}, fn _, {xs, ys, zs} ->
    theta = :rand.uniform() * 2 * :math.pi()
    phi = :rand.uniform() * :math.pi()
    x = :math.sin(phi) * :math.cos(theta)
    y = :math.sin(phi) * :math.sin(theta)
    z = :math.cos(phi)
    {[x | xs], [y | ys], [z | zs]}
  end)

Figure.new()
|> Figure.add_trace(
  Mesh3d.new(
    x: xs,
    y: ys,
    z: zs,
    alphahull: 5,
    opacity: 0.4,
    color: "cyan"
  )
)
|> Figure.update_layout(
  title: "Simple 3D Mesh (alphahull=5)",
  scene: %{xaxis: %{title: "X"}, yaxis: %{title: "Y"}, zaxis: %{title: "Z"}}
)
|> Plotly.show()