Univiewer is a visualisation program for HEALPix maps. It is written in C++ and uses OpenGL and the wxWidgets library for cross-platform portability. Using it you can:

  • Rotate and zoom maps on the sphere in 3D;
  • Create high-resolution views of square patches of the map;
  • Change maximum and minimum values of the colourmap interactively;
  • Calculate the power spectrum of the full-sky map or a patch;
  • Display any column of a HEALPix map FITS file on the sphere.

Since Univiewer uses OpenGL for 3D graphics, its performance is dependent your video card. It has been tested successfuly on computers with as little as 8Mb video memory, but it is recommended to have at least 32Mb to get good peformance.

In the 3D view, a HEALPix map is projected onto a ECP pixelation to create a texture which is wrapped around the sphere. In calculating the power spectrum, the spherical harmonic transforms are computed using the same ECP pixelation. This inevitably leads to some discrepancies at small scales due to repixelation effects, but they are reasonably small.


Univiewer main window. A tree view shows a list of open windows and information about the maps displayed in them.

Changing the colourmap.

Changing the minimum and maximum values of the colourmap makes it easy to inspect faint structure.

Any section of the sky can be projected onto a square patch and viewed at full resolution.

The power spectrum can be calculated for the full sky and for any projected patch of the sky.


Univiewer has been tested on a number of Unix/Linux platforms and on Windows XP. To install it you need:



  • Windows XP: Unpack archives, copy shared librares *.dll to c:\windows\system32 folder. Run wxMSW-2.8.9-Setup.exe to install wxMSW library. Run univiewer-1.63.exe.
  • Unix/Linux source: Check that all necessary libraries and their development packages are installed. Unpack the tarball archive and run ./configure, then use "make" to compile the program. See README file in the tar archive.


Lead developer:

Shamil M. Mingaliev (shamil.mingaliev@gmail.com)

With help from:

Mark Ashdown (maja1@mrao.cam.ac.uk)
Vlad Stolyarov (vlad@ast.cam.ac.uk)

The developers acknowledge support from the Astrophysics Group, Cavendish Laboratory who sponsored the visit of SMM to the UK.

We welcome feedback and suggestions to help us improve the code in the development of Univiewer version 2. Please send all bug reports to the above email addresses.