Storage for a set of point masses in structure-of-arrays layout. More...

#include <orrery/core/particle_data.hpp>

Public Member Functions
	ParticleData (Index count)
	Create count particles with every component zero.
Index	size () const noexcept
bool	empty () const noexcept
Index	capacity () const noexcept
	The number of particles the arrays can hold without reallocating.
void	reserve (Index count)
	Make room for count particles without changing how many there are.
void	resize (Index count)
	Change the number of particles, zero-filling any that are new.
void	clear () noexcept
	Remove every particle, keeping the storage for reuse.
Index	add (Vec3 position, Vec3 velocity, Real mass)
	Append one particle with zero acceleration and return its index.
Vec3Span< Real >	positions () noexcept
Vec3Span< const Real >	positions () const noexcept
Vec3Span< Real >	velocities () noexcept
Vec3Span< const Real >	velocities () const noexcept
Vec3Span< Real >	accelerations () noexcept
Vec3Span< const Real >	accelerations () const noexcept
std::span< Real >	masses () noexcept
std::span< const Real >	masses () const noexcept

Detailed Description

Storage for a set of point masses in structure-of-arrays layout.

The class invariant is that all ten component arrays hold exactly size() elements. Every operation that can change a length goes through one private helper that applies it to all ten, so an array cannot be forgotten, and an eleventh added later is caught at the one place that lists them rather than at each of the four operations that resize them.

Constructor & Destructor Documentation

◆ ParticleData()

orrery::core::ParticleData::ParticleData ( Index count )

explicit

Create count particles with every component zero.

Zero rather than uninitialised, and deliberately so: a particle of zero mass at the origin with no velocity exerts no force and feels the forces it is given, so a container that has been sized but not yet filled by an initial-condition generator perturbs nothing. Reading uninitialised storage would instead make a partially filled container produce results that vary between runs.

Member Function Documentation

◆ capacity()

Index orrery::core::ParticleData::capacity ( ) const

inlinenodiscardnoexcept

The number of particles the arrays can hold without reallocating.

Reported from one array because the ten are grown together and always agree, for the same reason their lengths do.

◆ add()

Index orrery::core::ParticleData::add	(	Vec3	position,
		Vec3	velocity,
		Real	mass )

Append one particle with zero acceleration and return its index.

For setup code and tests. Initial-condition generators that know their particle count size the container once and write through the views instead, which is both faster and how the solvers see the data.

The documentation for this class was generated from the following file:

orrery/core/particle_data.hpp