5.9 KiB
How to compile openGJK
Using openGJK is very simple. This guide will help you getting started compiling and using openGJK.
Requirements
Common requirements
- A C compiler
- CMake version 3.5 or above
Building
First, you need to configure the compilation, using CMake.
- Go inside the
build
dir. Create it if it doesn't exist. - Move into
build
dir and usecmake ..
. On Windows you can specifycmake -G "Visual Studio 15 2017 Win64" ..
, on Unixcmake -G "Unix Makefiles" ..
.
CMake standard options
- CMAKE_BUILD_TYPE: The type of build (can be Debug or Release)
- CMAKE_C_COMPILER: The path to the C compiler
CMake options defined for openGJK
Options are defined in the following files:
- CmakeOptions.cmake
They can be changed with the -D option:
cmake -DVERSION_ACCURATE=ON ..
In addition to passing options on the command line, you can browse and edit
CMake options using cmakesetup
(Windows), cmake-gui
or ccmake
(GNU/Linux
and MacOS X).
- Go to the build dir
- On Windows: run
cmakesetup
- On GNU/Linux and MacOS X: run
ccmake ..
Install and run
If all above building commands were executed from build
, the openGJK library can be found in the build/src
directory.
You can run the binaries in build/examples/*
.
To install the library copy the header file openGJK.h and the binaries in a folder accessible in the search path by all users (on Unix this would normally be /usr/local).
Testing
TO REWRITE!!
As mention above you can turn on the unit tests and make it possible to easily execute them:
cmake -DCMAKE_BUILD_TYPE=Debug -DUNIT_TESTING=ON ..
After that you can simply call make test
in the build directory or if you
want more output simply call ctest -V
.
If you want to enable the generation of coverage files you can do this by using the following options:
cmake -DCMAKE_BUILD_TYPE=Profiling -DUNIT_TESTING=ON ..
After building it you will see that you have several coverage options in
make help
You should have make ExperimentalCoverage
and running it will create
coverage files. The result is stored in Testing directory.
Examples
This section presents three examples on how to use openGJK with C, C# and Matlab.
C
This example illustrates how to include openGJK in an existing C program.
All files for the example are in the example1_c
folder. The executable built with
CMake reads the coordinates of two polytopes from the input files,
respectively userP.dat and userQ.dat, and computes the minimum distance
between them.
Notice that the input files must be in the folder from which the executable is launched, otherwise an error is returned.
You can edit the coordinates in the input file to test different polytopes; just remember to edit also the first number in the files that corresponds to the numbers of vertices that the program will read.
Matlab
This example illustrates how to invoke openGJK as a regular built-in Matlab function. You will need to build mex files (find out the requisites from Mathworks documentation).
Open Matlab and cd into the example2_mex
folder. By running the
script runme.m
, Matlab will first compile a mex file (telling you
about the name of the mex file generated) and will call the script
main.m
. This invokes openGJK within Matlab and illustrates the
result.
The mex file may be copied and called from any other Matlab project.
C#
This example illustrates how to invoke openGJK in an applications written in C#. You will need mono and Microsoft Visual Studio toolchain for C# on Windows.
The only file required is in the example3_csharp
folder. This can be compiled in Unix
with mono, or in Windows using Visual Studio. Notice that, however, the openGJK library
is compiled for a specific architecture (usually x64), and this breaks the portability
of the .NET application compiled in this example.
Below are the steps for compiling the C# application on Windows and Linux. Both procedures assume the dynamic library of openGJK has been already compiled.
Compile on Windows
- Move into the folder
example3_csharp
and create a new folderexample3
. - Copy into this folder the openGJK library or make it available in any directory.
- Open Visual Studio and create a new project. As project type select Console App (.NET Framework).
- Add to this project the
main.cs
file - Set x64 as the target platform, compile the application and run it.
Compile on Linux
- Move into the folder
example3_csharp
and create a new folderexample3
. - Copy into this folder the openGJK library or install is so that is available in any directory.
- Move into that new folder and open a terminal.
- Type
mcs -out:example3demo -d:UNIX ../main.cs
- Run the example by typing
mono example3demo
API user reference
double gjk( struct bodyA, struct bodyB, struct simplex)
Documentation
The folder doc
contains a Doxygen file for generating the documentation of the whole
library. To build the documentation cd into doc
and call Doxygen from the command line simply by typing doxygen
. If correctly installed, Doxygen will create html documentation with graphs illustrating the call stack of the functions of the library.
Parameters
- bodyA The first body.
- bodyB The second body.
- simplex The simplex used the GJK algorithm at the first iteration.
Returns
- double the minimum distance between bodyA and bodyB.
Description
The function gjk
computes the minimum Euclidean distance between two bodies using the
GJK algorithm. Note that the simplex used at the first iteration may be initialised by the user, but this is not necessary.