Integrator2 library

CUDA-based library for integration of the Newtonian potential and its gradient in 3D. Contents of the repository:

• source code of the shared library;
• test application for integration in 3D;
• examples of meshes in .dat format.

Doxygen-generated documentation is available.

Library compilation

Dependencies

• C++ compiler (tested on MS VC++ 2022 and GCC 7.4.0 and 9.4.0);
• CMake 3.18 or newer;
• CUDA Toolkit (tested on versions 10.1, 11.6, 12.1 and 12.3).

Build process

CMake BUILD_TESTS option (ON by default) controls the build of the test application.

mkdir build
mkdir install
cd build
cmake ..
make -j install

Test application

Test app reads the mesh and performs calculation over all existing pairs of neighboring cells.

Available command line options:

Short option	Long option	Purpose
-h	--help	Print the help message
-f <filename>	--meshfile=<filename>	Input mesh file name (required argument)
-s <number>	--scale=<number>	Scale factor for the input mesh
	--exporttoobj	Export the original/refined mesh to the OBJ file
	--exporttovtk	Export the original/refined mesh to the VTK (.vtp) file. Number of refinements is saved for each original cell in case of automatic error control
	--exporttocsv	Export the results of integration into csv files (different files for different types of neighbors)
	--exportresults	Export the results of integration into text files (different files for different types of neighbors)
-r <number>	--refine=<number>	Number of refinement iterations for the whole mesh (in case of 0 the original mesh is used)
-c	--checkresults	Check correctness of integration by comparing integrals for (i, j) and (j, i) pairs. Resulting error can be saved together with integral values

Example:

integrator2test3D.exe -f ..\..\examples\s5m.dat -s 0.0005 --exporttocsv --exporttovtk

Noticeable examples

List of the examples includes the following (including preferable value of the scale parameter):

Surface	File name	No. of vertices	No. of triangles	Scale
Sphere	G1.dat	55	112	1.0
Fish	Fish.dat	1603	3194	100.0
Airfoil	Krylo01.dat	373	854	1.0
Kettlebell	Girja.dat	318	743	1.0
Airplane (coarse mesh)	s5m.dat	1004	1864	0.0005
Airplane (fine mesh)	s5m2.dat	4086	7830	0.0005
Propeller	Vint16k.dat	8467	17774	1.0