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GPUParticles3D

Inherits: GeometryInstance3D < VisualInstance3D < Node3D < Node < Object

A 3D particle emitter.

Description

3D particle node used to create a variety of particle systems and effects. GPUParticles3D features an emitter that generates some number of particles at a given rate.

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

Tutorials

Properties

int

amount

8

float

amount_ratio

1.0

float

collision_base_size

0.01

DrawOrder

draw_order

0

Mesh

draw_pass_1

Mesh

draw_pass_2

Mesh

draw_pass_3

Mesh

draw_pass_4

int

draw_passes

1

Skin

draw_skin

bool

emitting

true

float

explosiveness

0.0

int

fixed_fps

30

bool

fract_delta

true

float

interp_to_end

0.0

bool

interpolate

true

float

lifetime

1.0

bool

local_coords

false

bool

one_shot

false

float

preprocess

0.0

Material

process_material

float

randomness

0.0

float

speed_scale

1.0

NodePath

sub_emitter

NodePath("")

bool

trail_enabled

false

float

trail_lifetime

0.3

TransformAlign

transform_align

0

AABB

visibility_aabb

AABB(-4, -4, -4, 8, 8, 8)

Methods

AABB

capture_aabb() const

void

convert_from_particles(particles: Node)

void

emit_particle(xform: Transform3D, velocity: Vector3, color: Color, custom: Color, flags: int)

Mesh

get_draw_pass_mesh(pass: int) const

void

restart()

void

set_draw_pass_mesh(pass: int, mesh: Mesh)

Signals

finished() 🔗

Emitted when all active particles have finished processing. To immediately restart the emission cycle, call restart.

This signal is never emitted when one_shot is disabled, as particles will be emitted and processed continuously.

Note: For one_shot emitters, due to the particles being computed on the GPU, there may be a short period after receiving the signal during which setting emitting to true will not restart the emission cycle. This delay is avoided by instead calling restart.

Enumerations

enum DrawOrder: 🔗

DrawOrder DRAW_ORDER_INDEX = 0

Particles are drawn in the order emitted.

DrawOrder DRAW_ORDER_LIFETIME = 1

Particles are drawn in order of remaining lifetime. In other words, the particle with the highest lifetime is drawn at the front.

DrawOrder DRAW_ORDER_REVERSE_LIFETIME = 2

Particles are drawn in reverse order of remaining lifetime. In other words, the particle with the lowest lifetime is drawn at the front.

DrawOrder DRAW_ORDER_VIEW_DEPTH = 3

Particles are drawn in order of depth.

enum EmitFlags: 🔗

EmitFlags EMIT_FLAG_POSITION = 1

Particle starts at the specified position.

EmitFlags EMIT_FLAG_ROTATION_SCALE = 2

Particle starts with specified rotation and scale.

EmitFlags EMIT_FLAG_VELOCITY = 4

Particle starts with the specified velocity vector, which defines the emission direction and speed.

EmitFlags EMIT_FLAG_COLOR = 8

Particle starts with specified color.

EmitFlags EMIT_FLAG_CUSTOM = 16

Particle starts with specified CUSTOM data.

enum TransformAlign: 🔗

TransformAlign TRANSFORM_ALIGN_DISABLED = 0

There is currently no description for this enum. Please help us by contributing one!

TransformAlign TRANSFORM_ALIGN_Z_BILLBOARD = 1

There is currently no description for this enum. Please help us by contributing one!

TransformAlign TRANSFORM_ALIGN_Y_TO_VELOCITY = 2

There is currently no description for this enum. Please help us by contributing one!

TransformAlign TRANSFORM_ALIGN_Z_BILLBOARD_Y_TO_VELOCITY = 3

There is currently no description for this enum. Please help us by contributing one!

Constants

MAX_DRAW_PASSES = 4 🔗

Maximum number of draw passes supported.

Property Descriptions

int amount = 8 🔗

  • void set_amount(value: int)

  • int get_amount()

The number of particles to emit in one emission cycle. The effective emission rate is (amount * amount_ratio) / lifetime particles per second. Higher values will increase GPU requirements, even if not all particles are visible at a given time or if amount_ratio is decreased.

Note: Changing this value will cause the particle system to restart. To avoid this, change amount_ratio instead.

float amount_ratio = 1.0 🔗

  • void set_amount_ratio(value: float)

  • float get_amount_ratio()

The ratio of particles that should actually be emitted. If set to a value lower than 1.0, this will set the amount of emitted particles throughout the lifetime to amount * amount_ratio. Unlike changing amount, changing amount_ratio while emitting does not affect already-emitted particles and doesn't cause the particle system to restart. amount_ratio can be used to create effects that make the number of emitted particles vary over time.

Note: Reducing the amount_ratio has no performance benefit, since resources need to be allocated and processed for the total amount of particles regardless of the amount_ratio. If you don't intend to change the number of particles emitted while the particles are emitting, make sure amount_ratio is set to 1 and change amount to your liking instead.

float collision_base_size = 0.01 🔗

  • void set_collision_base_size(value: float)

  • float get_collision_base_size()

The base diameter for particle collision in meters. If particles appear to sink into the ground when colliding, increase this value. If particles appear to float when colliding, decrease this value. Only effective if ParticleProcessMaterial.collision_mode is ParticleProcessMaterial.COLLISION_RIGID or ParticleProcessMaterial.COLLISION_HIDE_ON_CONTACT.

Note: Particles always have a spherical collision shape.

DrawOrder draw_order = 0 🔗

Particle draw order. Uses DrawOrder values.

Note: DRAW_ORDER_INDEX is the only option that supports motion vectors for effects like TAA. It is suggested to use this draw order if the particles are opaque to fix ghosting artifacts.

Mesh draw_pass_1 🔗

  • void set_draw_pass_mesh(pass: int, mesh: Mesh)

  • Mesh get_draw_pass_mesh(pass: int) const

Mesh that is drawn for the first draw pass.

Mesh draw_pass_2 🔗

  • void set_draw_pass_mesh(pass: int, mesh: Mesh)

  • Mesh get_draw_pass_mesh(pass: int) const

Mesh that is drawn for the second draw pass.

Mesh draw_pass_3 🔗

  • void set_draw_pass_mesh(pass: int, mesh: Mesh)

  • Mesh get_draw_pass_mesh(pass: int) const

Mesh that is drawn for the third draw pass.

Mesh draw_pass_4 🔗

  • void set_draw_pass_mesh(pass: int, mesh: Mesh)

  • Mesh get_draw_pass_mesh(pass: int) const

Mesh that is drawn for the fourth draw pass.

int draw_passes = 1 🔗

  • void set_draw_passes(value: int)

  • int get_draw_passes()

The number of draw passes when rendering particles.

Skin draw_skin 🔗

  • void set_skin(value: Skin)

  • Skin get_skin()

There is currently no description for this property. Please help us by contributing one!

bool emitting = true 🔗

  • void set_emitting(value: bool)

  • bool is_emitting()

If true, particles are being emitted. emitting can be used to start and stop particles from emitting. However, if one_shot is true setting emitting to true will not restart the emission cycle unless all active particles have finished processing. Use the finished signal to be notified once all active particles finish processing.

Note: For one_shot emitters, due to the particles being computed on the GPU, there may be a short period after receiving the finished signal during which setting this to true will not restart the emission cycle.

Tip: If your one_shot emitter needs to immediately restart emitting particles once finished signal is received, consider calling restart instead of setting emitting.

float explosiveness = 0.0 🔗

  • void set_explosiveness_ratio(value: float)

  • float get_explosiveness_ratio()

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

int fixed_fps = 30 🔗

  • void set_fixed_fps(value: int)

  • int get_fixed_fps()

The particle system's frame rate is fixed to a value. For example, 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 = true 🔗

  • void set_fractional_delta(value: bool)

  • bool get_fractional_delta()

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

float interp_to_end = 0.0 🔗

  • void set_interp_to_end(value: float)

  • float get_interp_to_end()

Causes all the particles in this node to interpolate towards the end of their lifetime.

Note: This only works when used with a ParticleProcessMaterial. It needs to be manually implemented for custom process shaders.

bool interpolate = true 🔗

  • void set_interpolate(value: bool)

  • bool get_interpolate()

Enables particle interpolation, which makes the particle movement smoother when their fixed_fps is lower than the screen refresh rate.

float lifetime = 1.0 🔗

  • void set_lifetime(value: float)

  • float get_lifetime()

The amount of time each particle will exist (in seconds). The effective emission rate is (amount * amount_ratio) / lifetime particles per second.

bool local_coords = false 🔗

  • void set_use_local_coordinates(value: bool)

  • bool get_use_local_coordinates()

If true, particles use the parent node's coordinate space (known as local coordinates). This will cause particles to move and rotate along the GPUParticles3D node (and its parents) when it is moved or rotated. If false, particles use global coordinates; they will not move or rotate along the GPUParticles3D node (and its parents) when it is moved or rotated.

bool one_shot = false 🔗

  • void set_one_shot(value: bool)

  • bool get_one_shot()

If true, only the number of particles equal to amount will be emitted.

float preprocess = 0.0 🔗

  • void set_pre_process_time(value: float)

  • float 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 🔗

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

float randomness = 0.0 🔗

  • void set_randomness_ratio(value: float)

  • float get_randomness_ratio()

Emission randomness ratio.

float speed_scale = 1.0 🔗

  • void set_speed_scale(value: float)

  • float get_speed_scale()

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

NodePath sub_emitter = NodePath("") 🔗

Path to another GPUParticles3D node that will be used as a subemitter (see ParticleProcessMaterial.sub_emitter_mode). Subemitters can be used to achieve effects such as fireworks, sparks on collision, bubbles popping into water drops, and more.

Note: When sub_emitter is set, the target GPUParticles3D node will no longer emit particles on its own.

bool trail_enabled = false 🔗

  • void set_trail_enabled(value: bool)

  • bool is_trail_enabled()

If true, enables particle trails using a mesh skinning system. Designed to work with RibbonTrailMesh and TubeTrailMesh.

Note: BaseMaterial3D.use_particle_trails must also be enabled on the particle mesh's material. Otherwise, setting trail_enabled to true will have no effect.

Note: Unlike GPUParticles2D, the number of trail sections and subdivisions is set in the RibbonTrailMesh or the TubeTrailMesh's properties.

float trail_lifetime = 0.3 🔗

  • void set_trail_lifetime(value: float)

  • float get_trail_lifetime()

The amount of time the particle's trail should represent (in seconds). Only effective if trail_enabled is true.

TransformAlign transform_align = 0 🔗

There is currently no description for this property. Please help us by contributing one!

AABB visibility_aabb = AABB(-4, -4, -4, 8, 8, 8) 🔗

  • void set_visibility_aabb(value: AABB)

  • AABB 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. GeometryInstance3D.extra_cull_margin is added on each of the AABB's axes. Particle collisions and attraction will only occur within this area.

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: visibility_aabb is overridden by GeometryInstance3D.custom_aabb if that property is set to a non-default value.

Method Descriptions

AABB capture_aabb() const 🔗

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

void convert_from_particles(particles: Node) 🔗

Sets this node's properties to match a given CPUParticles3D node.

void emit_particle(xform: Transform3D, velocity: Vector3, color: Color, custom: Color, flags: int) 🔗

Emits a single particle. Whether xform, velocity, color and custom are applied depends on the value of flags. See EmitFlags.

The default ParticleProcessMaterial will overwrite color and use the contents of custom as (rotation, age, animation, lifetime).

Mesh get_draw_pass_mesh(pass: int) const 🔗

Returns the Mesh that is drawn at index pass.

void restart() 🔗

Restarts the particle emission cycle, clearing existing particles. To avoid particles vanishing from the viewport, wait for the finished signal before calling.

Note: The finished signal is only emitted by one_shot emitters.

void set_draw_pass_mesh(pass: int, mesh: Mesh) 🔗

Sets the Mesh that is drawn at index pass.