unreal.NiagaraEmitter

class unreal.NiagaraEmitter(outer=None, name='None')

Bases: unreal.Object

UNiagaraEmitter stores the attributes of an FNiagaraEmitterInstance that need to be serialized and are used for its initialization

C++ Source:

  • Plugin: Niagara

  • Module: Niagara

  • File: NiagaraEmitter.h

Editor Properties: (see get_editor_property/set_editor_property)

  • allocation_mode (ParticleAllocationMode): [Read-Write] Allocation Mode: The emitter needs to allocate memory for the particles each tick. To prevent reallocations, the emitter should allocate as much memory as is needed for the max particle count. This setting controls if the allocation size should be automatically determined or manually entered.

  • attributes_to_preserve (Array(str)): [Read-Write] Attributes to Preserve: An allow list of Particle attributes (e.g. “Particle.Position” or “Particle.Age”) that will not be removed from the DataSet even if they aren’t read by the VM.

    Used in conjunction with UNiagaraSystem::bTrimAttributes

  • category (Text): [Read-Write] Category: Category to collate this emitter into for “add new emitter” dialogs.

  • combine_event_spawn (bool): [Read-Write] Combine Event Spawn: Performance option to allow event based spawning to be combined into a single spawn. This will result in a single exec from 0 to number of particles rather than several, when using ExecIndex() it is recommended not to do this.

  • determinism (bool): [Read-Write] Determinism: Toggles whether to globally make the random number generator be deterministic or non-deterministic. Any random calculation that is set to the emitter defaults will inherit this value. It is still possible to tweak individual random to be deterministic or not. In this case deterministic means that it will return the same results for the same configuration of the emitter as long as delta time is not variable. Any changes to the emitter’s individual scripts will adjust the results.

  • event_handler_script_props (Array(NiagaraEventScriptProperties)): [Read-Write] Event Handler Script Props

  • fixed_bounds (bool): [Read-Write] Fixed Bounds: Whether or not fixed bounds are enabled.

  • fixed_bounds (Box): [Read-Write] Fixed Bounds: The fixed bounding box value. bFixedBounds is the condition whether the fixed bounds can be edited.

  • interpolated_spawning (bool): [Read-Write] Interpolated Spawning: When enabled, this will spawn using interpolated parameter values and perform a partial update at spawn time. This adds significant additional cost for spawning but will produce much smoother spawning for high spawn rates, erratic frame rates and fast moving emitters.

  • library_visibility (NiagaraScriptLibraryVisibility): [Read-Write] Library Visibility: If this emitter is exposed to the library, or should be explicitly hidden.

  • limit_delta_time (bool): [Read-Write] Limit Delta Time: Whether to limit the max tick delta time or not.

  • local_space (bool): [Read-Write] Local Space: Toggles whether or not the particles within this emitter are relative to the emitter origin or in global space.

  • max_delta_time_per_tick (float): [Read-Write] Max Delta Time Per Tick: Limits the delta time per tick to prevent simulation spikes due to frame lags.

  • max_gpu_particles_spawn_per_frame (int32): [Read-Write] Max GPUParticles Spawn Per Frame: An override on the max number of GPU particles we expect to spawn in a single frame. A value of 0 means it’ll use fx.MaxNiagaraGPUParticlesSpawnPerFrame.

  • platforms (NiagaraPlatformSet): [Read-Write] Platforms

  • pre_allocation_count (int32): [Read-Write] Pre Allocation Count: The emitter will allocate at least this many particles on it’s first tick. This can aid performance by avoiding many allocations as an emitter ramps up to it’s max size.

  • random_seed (int32): [Read-Write] Random Seed: An emitter-based seed for the deterministic random number generator.

  • requires_persistent_i_ds (bool): [Read-Write] Requires Persistent IDs: Do particles in this emitter require a persistent ID?

  • scalability_overrides (NiagaraEmitterScalabilityOverrides): [Read-Write] Scalability Overrides

  • sim_target (NiagaraSimTarget): [Read-Write] Sim Target

  • template_asset_description (Text): [Read-Write] Template Asset Description

  • template_specification (NiagaraScriptTemplateSpecification): [Read-Write] Template Specification: If this emitter is a standard parent emitter, a template or a behavior example. Templates and behavior examples get copied rather than inherited from.