Diffuse

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

Section

lighting.diffuse controls the intensity of angle-dependent (Lambertian) lighting — how much the surface brightens when facing the light source. Range is 0.0 to 1.0. Default is 0.8.

alias Plotly.{Figure, Surface}

z = for i <- 0..24 do
  for j <- 0..24 do
    r = :math.sqrt((i - 12) * (i - 12) + (j - 12) * (j - 12))
    if r < 12, do: :math.sqrt(max(0, 144 - r * r)), else: 0
  end
end

Figure.new()
|> Figure.add_trace(Surface.new(z: z, colorscale: "Viridis", lighting: %{diffuse: 0.1}))
|> Figure.update_layout(title: "Diffuse: 0.1 (minimal angle effect)")
|> Plotly.show()

Figure.new()
|> Figure.add_trace(Surface.new(z: z, colorscale: "Viridis", lighting: %{diffuse: 1.0}))
|> Figure.update_layout(title: "Diffuse: 1.0 (strong angle effect)")
|> Plotly.show()