Particles

Particles

Inherits: GeometryInstance < VisualInstance < CullInstance < Spatial < Node < Object

GPU-based 3D particle emitter.

Description

3D particle node used to create a variety of particle systems and effects. Particles features an emitter that generates some number of particles at a given rate.

Use the process_material property to add a ParticlesMaterial to configure particle appearance and behavior. Alternatively, you can add a ShaderMaterial which will be applied to all particles.

Note: Particles only work when using the GLES3 renderer. If using the GLES2 renderer, use CPUParticles instead. You can convert Particles to CPUParticles by selecting the node, clicking the Particles menu at the top of the 3D editor viewport then choosing Convert to CPUParticles.

Note: After working on a Particles node, remember to update its visibility_aabb by selecting it, clicking the Particles menu at the top of the 3D editor viewport then choose Generate Visibility AABB. Otherwise, particles may suddenly disappear depending on the camera position and angle.

Tutorials

Properties

int	amount	`8`
DrawOrder	draw_order	`0`
Mesh	draw_pass_1
Mesh	draw_pass_2
Mesh	draw_pass_3
Mesh	draw_pass_4
int	draw_passes	`1`
bool	emitting	`true`
float	explosiveness	`0.0`
int	fixed_fps	`0`
bool	fract_delta	`true`
float	lifetime	`1.0`
bool	local_coords	`true`
bool	one_shot	`false`
float	preprocess	`0.0`
Material	process_material
float	randomness	`0.0`
float	speed_scale	`1.0`
AABB	visibility_aabb	`AABB( -4, -4, -4, 8, 8, 8 )`

Methods

AABB	capture_aabb ( ) const
Mesh	get_draw_pass_mesh ( int pass ) const
void	restart ( )
void	set_draw_pass_mesh ( int pass, Mesh mesh )

Enumerations

enum DrawOrder:

DRAW_ORDER_INDEX = 0 —- Particles are drawn in the order emitted.
DRAW_ORDER_LIFETIME = 1 —- Particles are drawn in order of remaining lifetime.
DRAW_ORDER_VIEW_DEPTH = 2 —- Particles are drawn in order of depth.

Constants

MAX_DRAW_PASSES = 4 —- Maximum number of draw passes supported.

Property Descriptions

int amount

Default	`8`
Setter	set_amount(value)
Getter	get_amount()

The number of particles emitted in one emission cycle (corresponding to the lifetime).

Note: Changing amount will reset the particle emission, therefore removing all particles that were already emitted before changing amount.

DrawOrder draw_order

Default	`0`
Setter	set_draw_order(value)
Getter	get_draw_order()

Particle draw order. Uses DrawOrder values.

Mesh draw_pass_1

Setter	set_draw_pass_mesh(value)
Getter	get_draw_pass_mesh()

Mesh that is drawn for the first draw pass.

Mesh draw_pass_2

Setter	set_draw_pass_mesh(value)
Getter	get_draw_pass_mesh()

Mesh that is drawn for the second draw pass.

Mesh draw_pass_3

Setter	set_draw_pass_mesh(value)
Getter	get_draw_pass_mesh()

Mesh that is drawn for the third draw pass.

Mesh draw_pass_4

Setter	set_draw_pass_mesh(value)
Getter	get_draw_pass_mesh()

Mesh that is drawn for the fourth draw pass.

int draw_passes

Default	`1`
Setter	set_draw_passes(value)
Getter	get_draw_passes()

The number of draw passes when rendering particles.

bool emitting

Default	`true`
Setter	set_emitting(value)
Getter	is_emitting()

If true, particles are being emitted.

float explosiveness

Default	`0.0`
Setter	set_explosiveness_ratio(value)
Getter	get_explosiveness_ratio()

Time ratio between each emission. If 0, particles are emitted continuously. If 1, all particles are emitted simultaneously.

int fixed_fps

Default	`0`
Setter	set_fixed_fps(value)
Getter	get_fixed_fps()

The particle system’s frame rate is fixed to a value. For instance, changing the value to 2 will make the particles render at 2 frames per second. Note this does not slow down the simulation of the particle system itself.

bool fract_delta

Default	`true`
Setter	set_fractional_delta(value)
Getter	get_fractional_delta()

If true, results in fractional delta calculation which has a smoother particles display effect.

float lifetime

Default	`1.0`
Setter	set_lifetime(value)
Getter	get_lifetime()

The amount of time each particle will exist (in seconds).

bool local_coords

Default	`true`
Setter	set_use_local_coordinates(value)
Getter	get_use_local_coordinates()

If true, particles use the parent node’s coordinate space. If false, they use global coordinates.

bool one_shot

Default	`false`
Setter	set_one_shot(value)
Getter	get_one_shot()

If true, only amount particles will be emitted.

float preprocess

Default	`0.0`
Setter	set_pre_process_time(value)
Getter	get_pre_process_time()

Amount of time to preprocess the particles before animation starts. Lets you start the animation some time after particles have started emitting.

Material process_material

Setter	set_process_material(value)
Getter	get_process_material()

Material for processing particles. Can be a ParticlesMaterial or a ShaderMaterial.

float randomness

Default	`0.0`
Setter	set_randomness_ratio(value)
Getter	get_randomness_ratio()

Emission randomness ratio.

float speed_scale

Default	`1.0`
Setter	set_speed_scale(value)
Getter	get_speed_scale()

Speed scaling ratio. A value of 0 can be used to pause the particles.

AABB visibility_aabb

Default	`AABB( -4, -4, -4, 8, 8, 8 )`
Setter	set_visibility_aabb(value)
Getter	get_visibility_aabb()

The AABB that determines the node’s region which needs to be visible on screen for the particle system to be active.

Grow the box if particles suddenly appear/disappear when the node enters/exits the screen. The AABB can be grown via code or with the Particles → Generate AABB editor tool.

Note: If the ParticlesMaterial in use is configured to cast shadows, you may want to enlarge this AABB to ensure the shadow is updated when particles are off-screen.

Method Descriptions

AABB capture_aabb ( ) const

Returns the axis-aligned bounding box that contains all the particles that are active in the current frame.

Mesh get_draw_pass_mesh ( int pass ) const

Returns the Mesh that is drawn at index pass.

void restart ( )

Restarts the particle emission, clearing existing particles.

void set_draw_pass_mesh ( int pass, Mesh mesh )

Sets the Mesh that is drawn at index pass.