Wind Arrows 3D

This example demonstrates how to render 3D wind vectors.

📋 まとめ

The sample data contains a longitude and latitude point cloud, along with sample winds provided in the form of three separate eastward (U), northward (V), and upward (W) vector components.

The vector components are measured relative to each spatial sample point in the point cloud.

No connectivity is provided within the sample data, so each point is a separate location in a field of scattered points, and each point has an associated wind vector independent of the others. We use the geovista.bridge.Transform.from_points() method, passing the winds with the vectors keyword, along with the associated sample points to generate a point cloud mesh with attached vectors.

The wind arrows are generated from this point cloud mesh via the pyvista.DataSetFilters.glyph() method, which scales each arrow in size and colour relative to the magnitude of its associated wind vector.

Note that, we use all 3 wind components and amplify the upward (W) vector component by a considerable factor for illustrative purposes. Vertical winds are generally much smaller in magnitude, and tend not to be very visible otherwise.

🏷 Tags: experimental 🧪 component: graticule component: texture component: vectors domain: meteorology filter: glyph load: vectors version: 0.6.0

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Static Scene

Interactive Scene

from __future__ import annotations

import pyvista as pv

import geovista as gv
from geovista.pantry.data import lfric_winds


def main() -> None:
    """Plot 3D wind arrows (UVW).

    Notes
    -----
    .. versionadded:: 0.6.0

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

    # Provide all three components, but with exaggerated upwards scaling bias.
    vectors = (sample.u, sample.v, sample.w * 1500.0)

    # Create the point cloud mesh with attached wind vectors from the
    # sample eastward (u), northward (v), and upward (w) components.
    mesh = gv.Transform.from_points(
        sample.lons,
        sample.lats,
        vectors=vectors,
        radius=1.1,
    )

    # Create a new mesh containing arrow glyphs, from the mesh vectors.
    # NOTE: choose an overall scaling factor to make the arrows a reasonable size.

    # Generate a mesh containing arrow glyphs from the wind vectors. Apply an
    # overall scaling factor to make the arrows a reasonable size, and colour
    # the arrows relative to their associated vector magnitude.
    arrows = mesh.glyph(factor=0.02, color_mode="vector")

    # Now render the plotter scene.
    p = gv.GeoPlotter()
    sargs = {"title": f"{sample.name} / {sample.units}"}
    p.add_mesh(arrows, cmap="inferno", scalar_bar_args=sargs)
    p.add_base_layer(texture=gv.natural_earth_hypsometric())
    p.add_graticule()

    # Define a specific camera position and orientation.
    cpos = pv.CameraPosition(
        position=(0.69178, -3.06569, 0.43180),
        focal_point=(0.41358, 0.07363, 0.50912),
        viewup=(0.80885, 0.05726, 0.58522),
    )
    p.camera.zoom(1.3)

    p.add_axes()
    p.show(cpos=cpos)


if __name__ == "__main__":
    main()