Stick points to surface of 3D map

Q&A
1

Hi,
I am trying to plot locations on a 3d map. However, I can’t get the points to stick to the 3d surface. What would be the best way to do this?

image
image1007×611 123 KB

2

Try this. Use a file with the long-lat (or X-Y) of your data. Then use grdtrack to add a 3rd column with the z value from your dem. Finally plot your data with plot3d (or psxyz).

3

Hi, below is my code. That is sort of what I do, but I think the zsize is somehow messing with everything.

minlon, maxlon = 16.98, 17.16
minlat, maxlat = -22.65, -22.47

grid = pygmt.datasets.load_earth_relief(resolution="01s", region=[minlon, maxlon, minlat, maxlat])
frame = ["xa1f0.25","ya1f0.25", "z2000+lmeters", "wSEnZ"]

pygmt.makecpt(
        cmap='earth',
        series=f'1400/2300/10',
        continuous=True
    )
fig = pygmt.Figure()
fig.grdview(
    grid=grid,
    region=[minlon, maxlon, minlat, maxlat, 1400, 2300],
    perspective=[315, 30],
    frame=frame,
    projection="M15c",
    zsize="4c",
    surftype="i",
    plane="1400+gazure",
    shading=-0.1,
    # Set the contour pen thickness to "1p"
    contourpen="1p",
)
fig.basemap(
    perspective=[315, 30],
    rose="jTL+w3c+l+o-2c/-1c"   # map directional rose at the top left corner
)

# Generate fake coordinates in the range for plotting
lons = minlon + np.random.rand(10) * (maxlon - minlon)
lats = minlat + np.random.rand(10) * (maxlat - minlat)

df = pd.DataFrame()
df['longitude'] = lons
df['latitude'] = lats

track = pygmt.grdtrack(points=df, grid=grid, newcolname="elevation")

fig.plot3d(
    x = track.longitude,
    y = track.latitude,
    z = track.elevation,
    style='c0.1i',
    color='blue',
    pen='black',
    label='something',
    zsize="4c",
)