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Sphere Plot Window
The Sphere Plot (
)
plots spherical polar coordinates in an isotropic 3-dimensional space.
Although the supplied coordinates are spherical polar,
the visible space is not necessarily centred on the coordinate origin,
and the visible axes are Cartesian.
In many respects this works like the
Cube Plot Window
See the Window Overview
for features common to all layer plots.
The positional coordinates are
Longitude and Latitude (in degrees) and
Radius.
Navigation is like that for the Cube Plot:
-
Panning
- Rotate the plot by holding the left mouse button.
It's also possible to rotate by using the rotation sliders in the
View tab of the
Axes control.
To re-centre the plot in the visible cube,
right-click
on the position you're interested in.
A screen position represents a line not a point, so there is a
degeneracy here; the new central position is actually the average
of data point positions near the mouse click. The upshot is that
if you click on a point or clump of interest, it should do what you want.
-
Zooming
- You can zoom using the mouse wheel or the zoom buttons
(
/
) on the toolbar.
Either of these zooms the data volume in the visible cube
about its centre, so the cube wireframe axes stay in the same place
on the screen, but the axis annotations move.
If you want to get zoom in or out on the cube wireframe itself,
you can do it using the Zoom Factor slider in the
View tab of the Axes
control.
The sphere plot offers the following plot controls:
Note that use of the
Auto and Density
shading modes can be confusing in 3 dimensions with multiple datasets.
This is because pixels based on density along a line of sight are not
located at any point on that line, so shaded pixels can't appear
at the "right" place in the 3-d space. The same applies to a lesser
extent with contours. They work fine with a single dataset though.
The Axes control (
) is described in
the next subsection.
Next Previous Up Contents
Next: Sphere Axes Control
Up: Layer Plot Windows
Previous: Cube Axes Control
TOPCAT - Tool for OPerations on Catalogues And Tables
Starlink User Note253
TOPCAT web page:
http://www.starlink.ac.uk/topcat/
Author email:
m.b.taylor@bristol.ac.uk
Mailing list:
topcat-user@bristol.ac.uk