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

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.


Default

0

Setter

set_draw_order(value)

Getter

get_draw_order()

Particle draw order. Uses DrawOrder values.


Setter

set_draw_pass_mesh(value)

Getter

get_draw_pass_mesh()

Mesh that is drawn for the first draw pass.


Setter

set_draw_pass_mesh(value)

Getter

get_draw_pass_mesh()

Mesh that is drawn for the second draw pass.


Setter

set_draw_pass_mesh(value)

Getter

get_draw_pass_mesh()

Mesh that is drawn for the third draw pass.


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.


Default

true

Setter

set_emitting(value)

Getter

is_emitting()

If true, particles are being emitted.


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.


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.


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.


Default

1.0

Setter

set_lifetime(value)

Getter

get_lifetime()

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


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.


Default

false

Setter

set_one_shot(value)

Getter

get_one_shot()

If true, only amount particles will be emitted.


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.


Setter

set_process_material(value)

Getter

get_process_material()

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


Default

0.0

Setter

set_randomness_ratio(value)

Getter

get_randomness_ratio()

Emission randomness ratio.


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.