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For general comments on plot navigation, see Appendix A.4.2.1.
Additional configuration options are available in the Navigation
tab of the Axes control.
Navigation in three dimensions with a two-dimensional screen and mouse
is a bit of a challenge. However, the actions listed below should make it
fairly straightforward to navigate around points in 3d space to zoom in
on the regions that you are interested in.
-
Left drag
-
Rotate.
Rotates the view cube about its center.
-
Wheel
-
Isotropic zoom.
Spinning the mouse wheel forwards/backwards zooms the space in the
view cube in/out around the cube center. The mouse position does not
affect it.
-
Right drag (CTRL-drag)
-
2d stretch zoom.
Dragging with the right button does a stretch zoom in the two dimensions
best aligned with the plane of the screen.
There is no movement in the third (mostly perpendicular to the screen)
direction.
The zoom is around a line defined by the position of the mouse at
the start of the zoom, pointing along the third dimension.
You can stretch/squash in both directions by dragging the mouse
up/down/left/right - it's easier to try it than to explain it.
-
Center drag (SHIFT-drag)
-
2d pan.
Dragging with the center button pans the 3d space in the two dimensions
best alighned with the plane of the screen.
There is no movement in the third (mostly perpendicular to the screen)
direction.
-
Left click
-
Select.
If there are plotted points near the cursor it will identify one,
plot a marker on it, and
activate it.
In 3d, it's not obvious which is the nearest point to a 2d cursor,
since a screen position represents a line not a point.
To break the degeneracy, the point used is the one nearest the
center of mass of plotted points along the line of sight represented
by the cursor position. The upshot of this is that if you click on
an isolated point, you'll pick that point, and if you click on a
dense cluster, you'll get a point near the center (of mass) of that
cluster.
-
Right click (CTRL-click)
-
Re-center.
Right-clicking identifies a position in a similar way to the
left-click Select action, and then translates the plot so that point
is at the center of the view cube. This means that clicking on a
cluster will put that cluster in the center of the cube.
If you click on an empty region, a position half way between front
and back of the cube at that X/Y position will be used.
You can also manually fix the plot bounds using the Range
tab of the Axes control.
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Up: Cube Plot Window
Previous: Cube Plot Window
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@jiscmail.ac.uk