compute_gravity.cc
No OneTemporary
Actions

Subscribers

None

File Metadata

	#include "compute_gravity.hh"
	#include <cmath>
	/* -------------------------------------------------------------------------- */
	void ComputeGravity::computePairInteraction(Particle& par1, Particle& par2) {
	// compute the distance vector and the square of distance

	auto v_r = par2.getPosition() - par1.getPosition();
	auto r2 = v_r.squaredNorm();

	if (r2 == 0.)
	return;

	// compute the distance
	auto r = sqrt(r2);
	v_r *= 1 / r;

	// compute the pair force
	auto force = par1.getMass() * par2.getMass() * G / r2 * v_r;

	// add up the force for both concerned particles
	par2.getForce() -= force;
	par1.getForce() += force;
	}

	/* -------------------------------------------------------------------------- */
	void ComputeGravity::setG(Real G) { this->G = G; }