.TH XDATASLICE 1 "1 February 1990"
.SH NAME
NCSA XDataSlice \- interactive 3D data analysis tool
.SH SYNOPSIS
.B xds
[-adjustToggles] [-installCMap] [-noInputFocus]
.RB [ " \-Xoptions \|.\|.\|." ]
.LP
.SH DESCRIPTION
.IX  XDataSlice  ""  "\fLXDataSlice\fR \(em interactive 3D data analysis tool"
.IP  
NCSA XDataSlice (xds) is a 3D interactive data analysis tool that features 
several methods of examining a 3D array of floating-point numbers.  One
prominent analysis method is to take 2D slices of the 3D dataset, along
the cartesian axes, or at any arbitrary angle.  The sliced numerical data is
then converted, on the fly, to raster images for the purpose of being better
visualized and understood.  If desired, the numerical slice can be placed in
a scrollable spreadsheet, with its corresponding image placed beside it for
reference.
.LP
.IP
Several slices can be generated as a batch with a user-specified increment
along the axis orthogonal to each slice, and they may be tiled alongside
one another for comparison.  Alternatively, they may be overlayed on top of
each another as an animation sequence, thus allowing the use of time as a
third dimension in visualizing the 3D dataset.
.LP
.IP
The relationship of slices orthogonal to one another may be further examined
by locating them together in the 3D bounding box outlining the limits of the
dataset.  The cartesian dicing tool built into XDataSlice is used for this
purpose.  Slices of various thicknesses or boxes of different sizes may be
selected and rendered in the 3D matrix with hidden surfaces removed, allowing
the user to view only what he/she deems interesting.
.LP
.IP
If the data in the 3D dataset is sparse or concentric, it is more useful to
view the 3D dataset as a whole.  The volumetric renderer featured by XDataSlice
allows the user to assign various transparency values to any number of
substances (defined by ranges of values in the dataset) that he/she may be
interested in.  These substances may then be rendered together, and the results
are translucent images akin to that of X-ray photographs.
.LP
.IP
At times, it may be desired to map out iso-surfaces within the 3D dataset, just
as one would want to get contour plots of 2D images.  The iso-surface renderer
in XDataSlice is sufficiently equipped to perform 3D edge tesselation and
render the surfaces (with hidden parts removed) with a single light source.
Views may be rendered with perspective projections and rotated at any angle
about the X-, Y- and Z- axes.  Animation sequences showing the views being
rotated in space may also be batched generated.
.LP
.IP
XDataSlice provides the ability to change the colormaps used for the
generated images.  These color maps may be created by NCSA XImage (ximage),
or some other NCSA software packages.  All generated images may be saved in
the NCSA Hierarchical Data Format (HDF) for further analysis by XImage
or other software.  They may also be read by XDataSlice for review.
.LP
.IP
As input data, XDataSlice takes HDF files containing either 8-bit raster
data or 32 bit 3D floating point data.  NCSA HDF is a standard data format
originally developed at NCSA.  As input palettes, it takes in HDF palettes,
and 8 bit palettes where the first 256 bytes specify the 256 entries of red,
the next 256 bytes specify 256 entries of green and the the last 256 bytes
specify the blue component.
.LP
.SH SEE ALSO
.IP
XImage(1)
.LP
Full documentation of NCSA XDataSlice is provided along with the distribution.
.LP
.SH BUGS
Please send bug reports to bugs@ncsa.uiuc.edu.
.IP
.SH ORIGIN
National Center for Supercomputing Applications at the University of Illinois
in Urbana Champaign.