Helix is applied mathematics library written in D programming language.
This is version 0.40 updated and maintained by Bill Baxter as part of the
OpenMesh library (only some OpenMesh demo Apps depend on it.  The 
OpenMesh library itself does not use Helix at all.)

For more info about OpenMesh see: http://www.dsource.org/projects/openmeshd

For the original, unmaintained version of Helix see: 
     http://www.dsource.org/projects/helix/
For documentation see 'doc' directory.

Note the license for Helix is different than for OpenMesh.

Here's the Helix license:
(Beware of the advertising clause that also applies to binary 
 distribution!)

/*
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

    Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

    Redistributions in binary form must reproduce the above
    copyright notice, this list of conditions and the following
    disclaimer in the documentation and/or other materials provided
    with the distribution.

    Neither name of Victor Nakoryakov nor the names of
    its contributors may be used to endorse or promote products
    derived from this software without specific prior written
    permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
OF THE POSSIBILITY OF SUCH DAMAGE.

Copyright (C) 2006. Victor Nakoryakov.
*/