Basic Ribbon Plot

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

Section

A ribbon plot is created from multiple Scatter3d traces with mode: "lines" and surfaceaxis: 1. surfaceaxis fills the area below the line onto the specified axis plane (0 = x, 1 = y, 2 = z). Each trace becomes one ribbon. surfacecolor: sets the fill color.

alias Plotly.{Figure, Scatter3d}

x_vals = [0, 1, 2, 3, 4, 5, 6, 7, 8]

ribbons = [
  {0, [1, 3, 2, 4, 5, 3, 4, 2, 3], "blue"},
  {1, [2, 4, 3, 1, 4, 2, 3, 5, 2], "green"},
  {2, [3, 2, 4, 5, 3, 2, 1, 3, 4], "red"}
]

fig =
  Enum.reduce(ribbons, Figure.new(), fn {y_pos, z_vals, color}, fig ->
    Figure.add_trace(
      fig,
      Scatter3d.new(
        x: x_vals,
        y: List.duplicate(y_pos, length(x_vals)),
        z: z_vals,
        mode: "lines",
        surfaceaxis: 1,
        surfacecolor: color,
        line: %{color: "black", width: 4}
      )
    )
  end)

fig
|> Figure.update_layout(
  title: "Ribbon Plot",
  showlegend: false,
  scene: %{
    xaxis: %{title: "X"},
    yaxis: %{title: "Category"},
    zaxis: %{title: "Value"}
  }
)
|> Plotly.show()