Confetti::Environment Class Reference

An external (to any particle or emitter) set of factors that affect a particle's position and velocity. More...

#include <Confetti/Environment.h>

Classes
struct	Surface
	A plane that the particles bounce against. More...

Public Types
using	Clipper = glm::vec4
	A plane that clips particles.
using	SurfaceList = std::vector< Surface >
	A list of Surfaces.
using	ClipperList = std::vector< Clipper >
	A list of Clippers.

Public Member Functions
	Environment (glm::vec3 const &gravity={ 0.0f, 0.0f, 0.0f }, float airFriction=0.0f, glm::vec3 const &windVelocity={ 0.0f, 0.0f, 0.0f }, float gustiness=0.0f, SurfaceList const &bpl=SurfaceList(), ClipperList const &cpl=ClipperList())
	Constructor. More...
void	setGravity (glm::vec3 const &gravity)
	Sets gravity.
glm::vec3	gravity () const
	Returns gravity.
void	setAirFriction (float airFriction)
	Sets air friction.
float	airFriction () const
	Returns air friction.
void	setWindVelocity (glm::vec3 const &wind)
	Sets wind velocity.
glm::vec3	windVelocity () const
	Returns wind velocity.
void	setGustiness (float gustiness)
	Sets gustiness.
float	gustiness () const
	Returns gustiness.
void	setSurfaces (SurfaceList const &bpl)
	Sets the list of surface.
SurfaceList const &	surfaces () const
	Returns the list of surface.
void	setClippers (ClipperList const &cpl)
	Sets the list of clip planes.
ClipperList const &	clippers () const
	Returns the list of clip planes.
void	update (float dt)
	Updates the environment. More...
glm::vec3	terminalVelocity () const
	Returns the terminal velocity.
glm::vec3	terminalDistance () const
	Returns the distance traveled by a particle at terminal velocity during the last update.
float	ect1 () const
	Returns the value 1.0f - exp( -airFriction_ * dt ) calculated during the last update.

Detailed Description

An external (to any particle or emitter) set of factors that affect a particle's position and velocity.

An environment contains the following factors. All factors are optional.

- gravity: Particles will accelerate according to the gravity acceleration vector.
- air friction: Particles will decelerate in the direction of motion according to the air friction value. This value is used
                to compute a terminal velocity, specifically wind velocity plus sqrt(gravity/airFriction). It represents a
                combination of the mass of the particle, the drag coefficient, the density of the air, and the projected
                area of the particle.
- wind: Particles can be affected by a wind that consists of a constant speed and direction modified randomly according to
        the gustiness factor. Gustiness is a constant acceleration applied to the wind velocity in a random direction.

Constructor & Destructor Documentation

Environment()

Confetti::Environment::Environment ( glm::vec3 const &  gravity = { 0.0f, 0.0f, 0.0f }, float  friction = 0.0f, glm::vec3 const &  windVelocity = { 0.0f, 0.0f, 0.0f }, float  gustiness = 0.0f, SurfaceList const &  bpl = SurfaceList(), ClipperList const &  cpl = ClipperList()  )

explicit

Constructor.

Parameters

gravity	Acceleration due to gravity (default: { 0.0f, 0.0f, 0.0f })
friction	Deceleration due to air friction as a fraction of gravity (default: 0.0f)
windVelocity	Prevalent wind velocity (default: { 0.0f, 0.0f, 0.0f })
gustiness	Gust acceleration value (default: 0.0f)
bpl	List of surfaces (default: SurfaceList())
cpl	List of clip planes (default: ClipperList())

Member Function Documentation

update()

void Confetti::Environment::update

(

float

dt

)

Updates the environment.

Parameters

dt	Amount of time (in seconds) passed since the last update.