This module generates 3D coordinate axes for a 3D data set. It will
also optionally generate tick marks along each axis, numeric labels
for the tick marks, and movable mesh planes perpendicular to each of
the axes.
Functionality has been added so that 2D rectilinear or uniform
fields will be accepted as well. The x/y coordinates are provided
with the field, the z coordinates for the axes are computed from the
data in the field.
INPUT
The input is an AVS field which must fit into one of the
following categories:
1. Uniform field, 2 or 3 data dimensions, with or without extents.
2. Rectilinear field, 2 or 3 data dimensions, with or without extents.
3. Irregular field, N-data dimensions, 3 spatial dimensions,
with or without extents.
The data type in the field is irrelevant. Only the coordinate
information is looked at.
OUTPUT
The output is a geometry object consisting of lines forming the axes,
with optional tick marks, mesh planes, and labels.
PARAMETERS
x axis ticks
y axis ticks
z axis ticks - These sliders set the number of ticks shown along
an axis.
tick size - This slider adjusts the size of the ticks marks.
xz plane position
xy plane position
yz plane position - These sliders set the position of the mesh planes.
This value is in the coordinate system of the axes,
rather than being a relative position along the
axes (as in previous releases).
Show xz plane
Show xy plane
Show yz plane - These switches turn the mesh planes on and off.
Mesh line spacing is determined by tick spacing,
so that if there are no ticks shown, there will be
no mesh planes shown regardless of the setting of
these switches.
font size - This slider sets the relative label font height.
label precision - This slider sets the number of digits shown to the
right of the decimal in the numeric labels.
font number - A slider used to select from 22 different fonts.
x label density
y label density
z label density - These sliders set the frequency of label display,
relative to tick marks. That is, if n is a label
density setting, a numeric label will be displayed
every n ticks along the axis.
origin labels - This is a type-in field which is scanned for an x,
y, and z. For any of these characters present in
the string, the origin numeric label appropriate
for the respective axis is displayed. This facility
is provided to reduce label confusion at the origin.
If all axis minimum (origin) values are the same,
that value is shown by default at the origin.
Show labels - This switch turns tick labeling on and off.
Axis Min
Axis Max - These type-in fields show, and allow adjustment of,
the axis minmum (origin) and maximum (end point)
values.
If the data set is UNIFORM, adjustment of these
fields simply changes the values of any displayed
numeric labels. This allows the user to make the
labeling better reflect the true dimensions of the
data.
Addendum to Uniform fields: Uniform fields may be mapped
into an arbitrary rectangle in space. 3D Axis may
be used to plot an axis with respect to the mapped
rectangle. If no extents are present in the
uniform field, the axes defaults to -1..1 in x,y,z.
If the data set is RECTILINEAR or IRREGULAR,
adjustment of these fields will change the actual
on sreen location of the chosen points, without
changing the labels on the unaffected part of the
axis. For example, if the initial minimum x co-
ordinate is 10, changing it to 0 would move the
axis origin 10 units in the negative x direction.
This would have the effect of moving the coordinate
axis system origin outside of the displayed data set.
But the tick labeled 10 would still be in the same
place and it would still be labeled 10.
(For further discussion refer to DATA MAPPING
below.)
DATA MAPPING
If the input is a UNIFORM data set then there are no coordinate
values stored in the data set and the coordinate axes, along with
the data, are drawn in normalized space (see Addendum above).
The axis origin is
placed in the far lower left corner of the displayed data set. The
initial axis min values are set to zero, and the max values are set
to the respective dimensions of the data set. These values, and
therefore the tick label values, are independent of the actual drawing
on screen.
If the input is a RECTILINEAR or IRREGULAR data set then the axes,
along with the data, are drawn in the world space of the data set. In
this case, the origin of the axis system is placed at the minimum
world value for each data dimension, and ticks are labeled accordingly.
(For a RECTILINEAR data set, this is typically the far lower left
corner of the displayed data set). Note that this may or may not
coincide with the world origin (0,0,0) which is defined by the data
set's stored coordinate information. For example, if the minimum
values of the data set coordinates for each axis is 10, then the point
(0,0,0) would lie outside of the data set. If the axis min or max
values are changed, then the drawn axis will change position or length,
but labels will remain consistant with the stored data set (world)
coordinates.