FVCOM Bathymetry

This example demonstrates how to render a warped unstructured triangular mesh.

📋 Summary

Creates a mesh from 1-D latitude and longitude unstructured cell points.

The resulting mesh contains triangular cells. The connectivity is required to construct the cells from the unstructured points.

It uses an unstructured grid Finite Volume Community Ocean Model (FVCOM) mesh of sea floor depth below geoid data.

Note that, the data is on the mesh faces/cells, but also on the nodes/points which can then be used to extrude the mesh to reveal the bathymetry of the Plymouth Sound and Tamar River in Cornwall, UK.

🏷 Tags: Unstructured Warp

---

Static Scene

Interactive Scene

from __future__ import annotations

import geovista as gv
from geovista.pantry.data import fvcom_tamar
import geovista.theme


def main() -> None:
    """Plot a warped FVCOM unstructured mesh.

    Notes
    -----
    .. versionadded:: 0.1.0

    """
    # Load the sample data.
    sample = fvcom_tamar()

    # Create the mesh from the sample data.
    mesh = gv.Transform.from_unstructured(
        sample.lons,
        sample.lats,
        connectivity=sample.connectivity,
        data=sample.face,
        name="face",
    )

    # Warp the mesh nodes by the bathymetry.
    mesh.point_data["node"] = sample.node
    mesh.compute_normals(cell_normals=False, point_normals=True, inplace=True)
    mesh.warp_by_scalar(scalars="node", inplace=True, factor=2e-5)

    # Plot the unstructured mesh.
    plotter = gv.GeoPlotter()
    sargs = {"title": f"{sample.name} / {sample.units}", "shadow": True}
    plotter.add_mesh(mesh, cmap="deep", scalars="face", scalar_bar_args=sargs)
    plotter.add_axes()
    plotter.add_text(
        "PML FVCOM Tamar",
        position="upper_left",
        font_size=10,
        shadow=True,
    )
    plotter.camera.zoom(1.2)
    plotter.show()


if __name__ == "__main__":
    main()