Example of advanced use of library libmmg3d

I/ Implementation

We read the mesh and solution in files.

• First we remesh in debug mode:
  • we ask for a minimal size of 0.001, a maximal size of 40, a gradation of 2 and a global hausdorff value (applied on all the boundaries) of 0.1;
  • we save the mesh and solution.
• Second, we remesh in normal mode, with specified memory and lower verbosity:
  • in addition to previous parameters, we ask that all boundary triangles of ref 36 respect a hasdorff number of 0.01 and all boundary triangles of ref 38 a hasdorff number of 1. For both reference, we set the minimal (resp. maximal) edge size to 0.00001 (resp. 40).
    The local hausdorff number on ref 38 has no effects because it is higher than the previous value (without local value, we apply global hausdorff (0.1)) and this value is now contained in the metric;
  • we don't save results but we reset the computed metric and reapply the initial constant metric of size 10;
  • we perform the last wave of refinment. Now we can see the effect of the local hausdorff number on ref 38;
  • we save the mesh and solution

II/ Compilation

1. Build and install the mmg3d shared and static library. We suppose in the following that you have installed the mmg3d library in the **_$CMAKE_INSTALL_PREFIX_** directory (see the installation section of the setup guide);
2. compile the main.c file specifying:
   • the mmg3d include directory with the -I option;
   • the mmg3d library location with the -L option;
   • the mmg3d library name with the -l option;
   • for the static library you must also link the executable with, if used for the mmg3d library compilation, the scotch and scotcherr libraries and with the math library;
   • with the shared library, you must add the ***_$CMAKE_INSTALL_PREFIX_** directory to your LD_LIBRARY_PATH.

‍Example 1
Command line to link the application with the mmg3d static library (we supposed here that the scotch library is installed in the **_$SCOTCH_PATH_** directory):

gcc -I$CMAKE_INSTALL_PREFIX/include/mmg/mmg3d main.c -L$CMAKE_INSTALL_PREFIX/lib -L$SCOTCH_PATH -lmmg3d -lscotch -lscotcherr -lm

‍Example 2
Command line to link the application with the mmg3d shared library:

gcc -I$CMAKE_INSTALL_PREFIX/include/mmg/mmg3d main.c -L$CMAKE_INSTALL_PREFIX/lib -lmmg3d
export LD_LIBRARY_PATH=$CMAKE_INSTALL_PREFIX/lib:$LD_LIBRARY_PATH