Note
Click here to download the full example code
Creating a 3D perspective image¶
Create 3-D perspective image or surface mesh from a grid
using pygmt.Figure.grdview
.
import pygmt
# Load sample earth relief data
grid = pygmt.datasets.load_earth_relief(resolution="05m", region=[-108, -103, 35, 40])
Out:
grdblend [NOTICE]: Remote data courtesy of GMT data server OCEANIA [https://oceania.generic-mapping-tools.org]
grdblend [NOTICE]: Earth Relief at 5x5 arc minutes from Gaussian Cartesian filtering (9 km fullwidth) of SRTM15+V2.1 [Tozer et al., 2019].
grdblend [NOTICE]: -> Download 180x180 degree grid tile (earth_relief_05m_p): S90W180
The pygmt.Figure.grdview
method takes the grid
input.
The perspective
argument changes the azimuth and elevation of the viewpoint; the
default is [180, 90], which is looking directly down on the figure and north is “up”.
The zsize
argument sets how tall the three-dimensional portion appears.
The default grid surface type is mesh plot.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
# Sets the view azimuth as 130 degrees, and the view elevation as 30 degrees
perspective=[130, 30],
# Sets the x- and y-axis labels, and annotates the west, south, and east axes
frame=["xa", "ya", "WSnE"],
# Sets a Mercator projection on a 15-centimeter figure
projection="M15c",
# Sets the height of the three-dimensional relief at 1.5 centimeters
zsize="1.5c",
)
fig.show()
Out:
<IPython.core.display.Image object>
The grid surface type can be set with the surftype
parameter.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
perspective=[130, 30],
frame=["xa", "ya", "WSnE"],
projection="M15c",
zsize="1.5c",
# Set the surftype to "surface"
surftype="s",
)
fig.show()
Out:
<IPython.core.display.Image object>
The default CPT is turbo and can be customized with the cmap
parameter.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
perspective=[130, 30],
frame=["xa", "yaf", "WSnE"],
projection="M15c",
zsize="1.5c",
surftype="s",
# Set the CPT to "geo"
cmap="geo",
)
fig.show()
Out:
<IPython.core.display.Image object>
The plane
argument sets the elevation and color of a plane that provides a fill
below the surface relief.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
perspective=[130, 30],
frame=["xa", "yaf", "WSnE"],
projection="M15c",
zsize="1.5c",
surftype="s",
cmap="geo",
# Set the plane elevation to 1,000 meters and make the fill "gray"
plane="1000+ggray",
)
fig.show()
Out:
<IPython.core.display.Image object>
The perspective
azimuth can be changed to set the direction that is “up”
in the figure.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
# Set the azimuth to -130 (230) degrees and the elevation to 30 degrees
perspective=[-130, 30],
frame=["xa", "yaf", "WSnE"],
projection="M15c",
zsize="1.5c",
surftype="s",
cmap="geo",
plane="1000+ggrey",
)
fig.show()
Out:
<IPython.core.display.Image object>
The contourpen
parameter sets the pen used to draw contour lines on the surface.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
perspective=[-130, 30],
frame=["xaf", "yaf", "WSnE"],
projection="M15c",
zsize="1.5c",
surftype="s",
cmap="geo",
plane="1000+ggrey",
# Set the contour pen thickness to "0.5p"
contourpen="0.5p",
)
fig.show()
Out:
<IPython.core.display.Image object>
pygmt.Figure.colorbar
can be used to add a color bar to the figure. The
cmap
argument does not need to be passed again. To keep the color bar’s alignment
similar to the figure, use True
as the perspective
argument.
fig = pygmt.Figure()
fig.grdview(
grid=grid,
perspective=[-130, 30],
frame=["xaf", "yaf", "WSnE"],
projection="M15c",
zsize="1.5c",
surftype="s",
cmap="geo",
plane="1000+ggrey",
contourpen="0.1p",
)
fig.colorbar(perspective=True, frame=["a500", "x+lElevation", "y+lm"])
fig.show()
Out:
<IPython.core.display.Image object>
Total running time of the script: ( 0 minutes 13.671 seconds)