Ben1980

C:.
|   .gitignore
|   CMakeLists.txt             (1)
|   LICENSE
|   README.md
|   
+---build                      (2)
+---cmake                      (3)
|       FindCatch.cmake
|       

Ben1980

mkdir build //(1) We need a build directory
cd build
cmake ..    //(2) Generating the the artifacts to build, if necesarry download Catch2 via -DDOWNLOAD_CATCH=1 parameter
make        //(3) Build the binaries on linux, for windows you might need different commands, e.g. msbuild gravity.sln for a visual studio based build
ctest       //(4) Running tests

Ben1980

cmake_minimum_required(VERSION 3.1...3.13)

if(${CMAKE_VERSION} VERSION_LESS 3.12)
    cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
endif()

project(gravity VERSION 0.1.0
    DESCRIPTION "N-Body-Problem project of https://thoughts-on-cpp.com"
    LANGUAGES CXX)

Ben1980

add_library(solver
    SHARED
    src/solver.cpp)

target_include_directories(solver 
    PUBLIC 
    include)

add_executable(solverTest 
    test/test-main.cpp

Ben1980

class MyClass {
public:
  int * getArray() const { 
    arr[0]++;
    return arr; 
  }
  void setFirstVal(int val) { arr[0] = val; }

private:
  int * arr = new int[10];

Ben1980

struct Complex {
  double real;
  double imaginary;
};

Ben1980

template<class RandomIt, class Compare>
constexpr void sort(RandomIt first, RandomIt last, Compare comp); //constexpr since C++ 20

Ben1980

std::vector<Complex> vec = { { 3, 1},
                             { 1, 9 },
                             { 8, 2 },
                             { 3, 14 }};

double Complex::*var;
auto comparator = [&var](const Complex &a, const Complex &b) { return a.*var < b.*var; };

var = &Complex::real; //Sorting for real numbers
std::sort(vec.begin(), vec.end(), comparator);

Ben1980

TEST_CASE( "Explicit euler algorithm with two point mass", "[euler]" ) {

    Solver solver;

    ParticleBuilder particleBuilder;

    Particle particleA = particleBuilder
            .position()
            .mass()
            .build();

Ben1980

double Inverse(double value) { return -value; }

Particle GenerateStandardParticle(double xPosition, double yPosition)
{
    ParticleBuilder particleBuilder;

    return particleBuilder
            .position({xPosition, yPosition})
            .mass(1e10)
            .build();