Introduction

VisIVO Server is a suite of software tools for creating customized views of 3D renderings from astrophysical data tables. Their defining characteristic is that no fixed limits are prescribed regarding the dimensionality of data tables input for processing, thus supporting very large scale datasets.

VisIVO Server consists of three core components: VisIVO Importer, VisIVO Filter and VisIVO Viewer respectively. Their functionality and usage is described in the following sections.

To create customized views of 3D renderings from astrophysical data tables, a two-stage process is employed. First, VisIVO Importer is utilized to convert user datasets into VisIVO Binary Table (VBT). Then, VisIVO Viewer is invoked to display customized views of 3D renderings.

As an example, consider displaying views from only three columns of an astrophysical data table supplied in ascii form, say col_1, col_2 and col_3, by using the commands

$ VisIVOImporter --fformat ascii UserDataSet.txt
$ VisIVOViewer -x col_1 -y col_2 -z col_3 --scale --glyphs pixel VBT.bin

VisIVOServer is distributed with GNU General Public License v2.0 License for NON COMMERCIAL use.

VisIVOServer source code is on GitHub.

Installation

To install VisIVO Server, follow the instructions indicated in the INSTALL.md file in the GitHub repository https://github.com/VisIVOLab/VisIVOServer.

VisIVO Binary Table

A VisIVO Binary Table (VBT) is a highly-efficient data representation used by VisIVO Server internally. A VBT is realized through a header file (extension .bin.head) containing all necessary metadata, and a raw data file (extension .bin) storing actual data values.

For example, the header may contain information regarding the overall number of fields and number of points for each field (for point datasets) or the number of cells and relevant mesh sizes (for volume datasets). The raw data file is typically a sequence of values, e.g. all X followed by all Y values.

Header

The header file contains the following fields:

float | double
n1
n2 [ GeoX GeoY GeoZ DX DY DZ ]
little | big
X
Y
Z
Vx
Vy
Vz

Where:

• float | double

  It is the data type of the storage variables used.

• n1

  It denotes the number of columns (fields) in the VBT (e.g. 6).

• n2

  It denotes the number of rows in the VBT (e.g. 262144).

• GeoX GeoY GeoZ DX DY DZ

  They are employed only if the VBT represents volumetric datasets.

  In that case GeoX, GeoY and GeoZ represent the mesh geometry, while DX, DY and DZ represent the x, y and z size of volumetric cells (e.g. 64 64 64 1.0 1.0 1.0).

• little | big

  It denotes the endianism employed in the VBT. After this field there exist n1 rows that indicate the VBT columns as positions (X, Y, Z) and velocities (Vx, Vy, Vz).