The particle class keeps a list of all of its instances.A particle system instance is always associated with a owner pointer, which is now the current scene object, such as a missile or a biped. More...

#include <particle.h>

Public Member Functions
void	update (SceneState *pSceneState, float dt)

void	ClearAllInstances ()
	clear all particle instances. More...

DeviceTexturePtr_type	GetDeviceTexture ()
	get associated texture

TextureEntity *	GetTexture ()

bool	AnimateExistingParticles (float dt, const Vector3 &vOffset, ParticleList *instancePS)
	only update existing particles More...

ParticleList *	GetCurrentInstance (SceneState *pSceneState, bool bForceCreate=true)
	get the current particle system instance according to the current scene object. More...

bool	DeleteInstance (void *owner)
	delete instances for a given scene object

void	setup (SceneState *pSceneState, int anim, int time)
	set the current animation ID and animation time, this function is usually called by its parent model to make them synchronized. More...

void	draw (SceneState *pSceneState)
	draw the current instance, if it is a non-absolute particle system instance. More...

void	drawInstance (ParticleList *instancePS)
	draw a specified instance. More...

void	drawAllAbsInstances ()
	draw all absolute instances.This is called for batch-rendering global(absolute) particle instances. More...

CParaXModel *	GetParent ()
	get the parent model. More...

void	DrawInstanceSub (ParticleList *instancePS)

void	SetTextureRowsCols (int nRows, int nCols)
	set how many rows and cols that the texture associated with this particle system is evenly divided into.

Public Attributes
Animated< float >	speed
	initial speed, the initial speed magnitude of a particle is V(0) = speed + variation * rand(-1,1).

Animated< float >	variation
	initial speed variation, the initial speed magnitude of a particle is V(0) = speed + variation * rand(-1,1).

Animated< float >	gravity
	particle acceleration magnitude along their current directions, shared by all existing particles at a given time , this is usually a positive constant like 9.8

Animated< float >	lifespan
	maxlife of a newly born particle in seconds

Animated< float >	rate
	how many particles to spawn per second.

Animated< float >	areal
	the half length of the emitter plane

Animated< float >	areaw
	the half width of the emitter plane

Animated< float >	spread
	RESERVED: this parameter is reserved for other emitter types.

Animated< float >	lat
	RESERVED: this parameter is reserved for other emitter types.

Animated< float >	grav2
	RESERVED: this parameter is reserved for other emitter types.

float	slowdown
	it controls how fast the speed magnitude of a particle dwindles as its life is approaching the end. More...

float	rotation

float	mid
	the color[0] and sizes[0] is the color and size of a particle at its birth the color[1] and sizes[1] is the color and size of a particle at when it is age is mid, assuming a lifespan in [0,1] the color[2] and sizes[2] is the color and size of a particle at its death for particle at any age [0,1], it will interpolate between these values linearly. More...

Vector4	colors [3]

float	sizes [3]

Vector3	pos
	all particles are offset by this value at its birth. this is usually V(0,0,0).

int	blend
	how the texture blending is applied to each particle. More...

int	order
	the triangle winding order of the quad: whether it is CCW(-1) or CW(0). It does not matter if particle is transparent.

int	type
	this is 0,1,2. More...

bool	billboard
	whether using billboard when during the particles. In most cases, this is true, because particles are usually drawn with triangle quads facing the camera.

int	rows

int	cols

std::vector< TexCoordSet >	tiles

int32	m_texture_index

Bone *	parent

ParticleEmitter *	emitter

CParaXModel *	model

float	tofs
	this is just a rand seed for this particle system.

map< void , ParticleList >	m_instances
	instances of the particle systems. More...

bool	rotate2SpeedDirection

Friends
class	PlaneParticleEmitter

class	SphereParticleEmitter

Detailed Description

The particle class keeps a list of all of its instances.A particle system instance is always associated with a owner pointer, which is now the current scene object, such as a missile or a biped.

The instance may be global or local. Global particles remain in the scene even after its owner object is released and is rendered as global object. The scene manager keeps a reference to all active particle systems and their instances. It will automatically delete instances that is no longer active in the current frame. It will also animate and render global PS instances whose owner has been destroyed. Particles in global particle systems should have a short(finite) life time, in order to clean themselves quickly after its owner is released.

Member Function Documentation

§ AnimateExistingParticles()

bool ParticleSystem::AnimateExistingParticles	(	float	dt,
		const Vector3 &	vOffset,
		ParticleList *	instancePS
	)

only update existing particles

Parameters

dt	time delta
vOffset	all position and origin will be offset by this value during animation. this is usually the render origin offset between two consecutive calls.
instancePS	particle system instance.

Returns: : return true if there is still particles in the instance.

§ ClearAllInstances()

void ParaEngine::ParticleSystem::ClearAllInstances ( )

clear all particle instances.

delete all particle system instances

§ draw()

void ParticleSystem::draw ( SceneState * pSceneState )

draw the current instance, if it is a non-absolute particle system instance.

get the particle system instance for the current scene object.

§ drawAllAbsInstances()

void ParticleSystem::drawAllAbsInstances ( )

draw all absolute instances.This is called for batch-rendering global(absolute) particle instances.

§ drawInstance()

void ParticleSystem::drawInstance ( ParticleList * instancePS )

draw a specified instance.

draw the particle system instance.

§ DrawInstanceSub()

void ParticleSystem::DrawInstanceSub ( ParticleList * instancePS )

each particle is rendered as a quad, which require 2 triangles or 6 vertices.

§ GetCurrentInstance()

ParticleList * ParticleSystem::GetCurrentInstance	(	SceneState *	pSceneState,
		bool	bForceCreate = `true`
	)

get the current particle system instance according to the current scene object.

Parameters

bForceCreate if this is true, the instance will be created if not found.

get the particle system instance for the current scene object.

§ GetParent()

CParaXModel* ParaEngine::ParticleSystem::GetParent ( )

inline

get the parent model.

§ setup()

void ParticleSystem::setup	(	SceneState *	pSceneState,
		int	anim,
		int	time
	)

set the current animation ID and animation time, this function is usually called by its parent model to make them synchronized.

§ update()

void ParticleSystem::update	(	SceneState *	pSceneState,
		float	dt
	)

get the particle system instance for the current scene object.

add this particle system to the scene state. so that the scene state will automatically maintain the life of this particle system instance.

mark as updated instance

animate existing particles.

spawn new particles Tricky: 2010.3.10: we will not spawn new particle at very low frame rate, such as 10FPS

Member Data Documentation

§ blend

int ParaEngine::ParticleSystem::blend

how the texture blending is applied to each particle.

In most cases, it is 2 ALPHA_BLEND or 4 ADDITIVE ALPHA. 0 for OPAQUE; 1 ADDITIVE BLEND; 2 ALPHA_BLEND(using alpha); 3 TRANSPARENT(using alpha testing); 4 ADDITIVE ALPHA;

§ m_instances

map<void*, ParticleList*> ParaEngine::ParticleSystem::m_instances

instances of the particle systems.

mapping from the owner object,typically this is a scene object, to the particle list of that owner

§ mid

float ParaEngine::ParticleSystem::mid

the color[0] and sizes[0] is the color and size of a particle at its birth the color[1] and sizes[1] is the color and size of a particle at when it is age is mid, assuming a lifespan in [0,1] the color[2] and sizes[2] is the color and size of a particle at its death for particle at any age [0,1], it will interpolate between these values linearly.

Age is defined as particle_time/life_span; In most cases, mid is 0.5, color[0] and color[2] are transparent;or sizes[0] and size[2] are zero, either of which will let particle fade in and out gracefully.

§ slowdown

float ParaEngine::ParticleSystem::slowdown

it controls how fast the speed magnitude of a particle dwindles as its life is approaching the end.

in formula, it is V*expf(-1.0f * slowdown * p.life), where p.life is the current life of a particle in seconds. if slowdown is infinitely small, there will be no slowed down; if it is big(such as 1), the particle will has no speed after just a few seconds from birth.

§ type

int ParaEngine::ParticleSystem::type

this is 0,1,2.

usually means how the particles are rendered.

0 or 2 means normal particle which is centered on the particle origin with a given size.
1 means that particle is rendered with origin at the particle system center and extends to the particle origin.

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

Client/trunk/ParaEngineClient/ParaXModel/particle.h
Client/trunk/ParaEngineClient/ParaXModel/particle.cpp

Public Member Functions

Public Attributes

Friends

Detailed Description

Member Function Documentation

§ AnimateExistingParticles()

§ ClearAllInstances()

§ draw()

§ drawAllAbsInstances()

§ drawInstance()

§ DrawInstanceSub()

§ GetCurrentInstance()

§ GetParent()

§ setup()

§ update()

Member Data Documentation

§ blend

§ m_instances

§ mid

§ slowdown

§ type