Requirements for running code

Computational Geometric Algorithms library : My code used version 2.0
Geomview : Used for viewing generated octrees

Installing

The installation part is tricky as you have to first install CGAL -2.0 or higher. The way the code has been integrated with CGAL, it is better if you follow the following procedure

Install CGAL.
Now untar the src archive file octree.tar.gz in the CGAL home directory.

cd CGAL_HOME;
tar xvzf octree.tar.gz

Now you will have to edit the makefile in octree/ directory - as CGAL installation will change certain path names. Typically you have to make the following changes

Set the variable CGAL_MAKEFILE accordingly.
Set the include flags - so that compiler looks for header files in octree/include directory

Now set the path variable so that it includes the directory octree/3dpmc. This is where the program for 3dpmc used by the code is there.

set PATH=$PATH:${CGAL_HOME}/octree/3dpmc

Now to compile 3dpmc program.

cd octree/3dpmc
gcc 3d_pmc.c -lm -o 3dpmc

Now to compile octree programs

                            cd octree
                     make test_octree
                     make cgal_poly_to_poly

Installation complete

Making it Run

Generating input files :

Input file for polyhedron : This has to be a file in OFF format. Examples in octree/data.
Input file for 3dpmc program : This is generated from file above.

cgal_poly_to_poly <off_file> > 3dpmc.in

Note : you must redirect the output to 3dpmc.in - no other filename

Running the program :

                                     test_octree <off_file> <result_file> <depth> where,

                                 off_file = input file in off format (see above)
                                 result file = file to be used for viewing in geomview
                                 depth = max depth of a node in the octree.

Finally viewing the file :

The program sometimes runs out of memory - so the output file - might be broken in sequence resulting in breaks in file. So some corrections have to be perfromed by hand. Edit the result file - the format is easy

LIST {

{

}

{

}

....

{

}

The LIST opening brace (show in purple) specifies a list of OFF objects octants in our case and the braces one level below (shown in red) are the octants : you need to insert one brace after the first opening brace for LIST. At the end if any octant is left out delete the octant and then close the LIST brace.

Now open the file in Geomview Voila !!!