Default Required and Spawn Modules

Modules that are included along with an emitter and required for its function.

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The following classes and modules always exist when a new emitter is created. They will always be present and cannot be deleted.

Required Module

Every particle emitter contains this module which contains all the properties that are required by a particle emitter. This includes the following:

Property

Description

Emitter

Material

The material to apply to the particles.

Emitter Origin

The point in 3D space where particles will be emitted from this emitter, unless otherwise specified by other modules.

Emitter Rotation

A local rotation applied to the emitter itself.

Screen Alignment

How the particle is oriented in relation to the camera. The following modes are allowed:

Flag

Description

FacingCameraPosition

Particles will rotate to face the camera position, but will ignore camera rotation.

Square

Uniform scale (forced to the X setting), facing the camera.

Rectangle

Non-uniform scale, facing the camera.

Velocity

Orient the particle towards both the camera and the direction the particle is moving. Non-uniform scaling is allowed.

TypeSpecific

Use the alignment method indicated in the type data module. (Mesh only)

Use Local Space

Indicates whether the particle emitter should apply the world transform of its parent ( false ) or not ( true ). When true , a particle emitter will perform all operations in local space.

Kill On Deactivate

Indicates whether the particle emitter should kill all particles on deactivation. If false , any living particles will complete their lifetime when the emitter is deactivated.

Kill On Completed

Indicates whether the particle system component should kill this emitter instance when it completes.

Sort mode

The sorting mode use for the emitter.

Mode

Description

PSORTMODE_None

No sorting is performed.

PSORTMODE_ViewProjDepth

Sort particles by depth based on the view projection.

PSORTMODE_DistanceToView

Sort particles by distance of the particle to the camera in world space.

PSORTMODE_Age_OldestFirst

Sort the particles by age, with oldest particle drawn first.

PSORTMODE_Age_NewestFirst

Sort the particles by age, with newest particle drawn first.

Use Legacy Emitter Time

If true , the EmitterTime for the emitter will be calculated by modulating the SecondsSinceCreation by the EmitterDuration. As this can lead to issues with looping and variable duration, a new approach has been implemented. If false , this new approach is utilized, and the EmitterTime is simply incremented by DeltaTime each tick. When the emitter loops, it adjusts the EmitterTime by the current EmitterDuration resulting in proper looping/delay behavior.

Orbit Module Affects Velocity Alignment

If true , movement generated by orbit modules is applied to velocity-aligned particles.

Duration

Emitter Duration

Indicates how long, in seconds, the emitter will run before looping. If set to 0, the emitter will never loop.

Emitter Duration Low

Gives the low-end of emitter duration to allow for variations in the duration of an emitter.

Emitter Duration Use Range

When true , the emitter will select a duration from the range of EmitterDurationLow to EmitterDuration when starting up.

Duration Recalc Each Loop

When true , the emitter will select a new duration from the range of EmitterDurationLow to EmitterDuration when looping.

Emitter Loops

The number of times to loop before going inactive. If set to 0, the emitter will run constantly, looping 'forever'.

Delay

Emitter Delay

The amount of time to delay starting the emitter. This allows for 'staggering' emitters within a single particle system. This also serves as the upper bound for choosing a random delay value when using a range.

Emitter Delay Low

The lower bound for choosing a random delay value when using a range.

Emitter Delay Use Range

If true , the effective delay value for the emitter will be a random value chosen from the range [Emitter Delay Low, Emitter Delay].

Delay First Loop Only

When true , and emitter with an EmitterDelay of greater than 0 and EmitterLoops greater than 1 will only perform the delay on the first loop.

Sub UV

The Sub UV data indicates that the emitter should utilize sub-images of the texture applied. This is useful for implementing simple animations on particles.

Interpolation Method

An enumeration indicating the method that should be utilized to interpolate between sub-images. This can be one of the following:

Method

Description

None

Do not apply SubUV modules to this emitter.

Linear

Smoothly transition between sub-images in the given order, with no blending between the current and the next.

Linear_Blend

Smoothly transition between sub-images in the given order, blending between the current and the next.

Random

Pick the next image at random, with no blending between the current and the next.

Random_Blend

Pick the next image at random, blending between the current and the next.

Sub Images_Horizontal

The number of sub-images in the texture on the horizontal (x) axis of the texture.

Sub Images_Vertical

The number of sub-images in the texture on the vertical (y) axis of the texture.

Scale UV

Indicates that the UV values should be scaled to properly `fit' the sub-image size. This is only used for mesh emitters.

Random Image Changes

The number of times to changes the image over the lifetime of the particle when InterpolationMethod is set to Random.

Macro UV

ParticleMacroUV

Override System Macro UV

If true , the settings here will override the system Macro UV settings, which can be seen by deselecting all emitters and modules in Cascade's Emitter List.

Macro UVPosition

The local space position from which all Macro UV calculations will originate.

Macro UVRadius

World radius beyond which any Macro UV materials will begin tiling.

Rendering

Use Max Draw Count

When true , the emitter will never draw more than MaxDrawCount particles. All particles will still be updated when ticking.

Max Draw Count

The number of particles to limit rendering to.

UV Flipping Mode

Enabled the flipping of Sprite and GPU particles UV's in a number of different ways.

Mode

Description

None

No UV flipping occurs. This is the default.

FlipUV

Flips the U and V texture coordinates.

U Only

Flips only the U texture coordinate.

V Only

Flips the V texture coordinate.

Random Flip UV

Randomly flips U and V together at spawn time.

Random Flip U Only

Randomly flips just U at spawn time.

Random Flip V Only

Randomly flips just V at spawn time.

Random Flip UV Independent

Randomly flips U and V independently at spawn time.

Normals

Emitter Normals Mode

The mode used to generate normals for this emitter LOD.

Mode

Description

ENM_CameraFacing

Default mode, normals are based on the camera facing geometry.

ENM_Spherical

Normals are generated from a sphere centered at NormalsSphereCenter.

ENM_Cylindrical

Normals are generated from a cylinder going through NormalsSphereCenter, in the direction NormalsCylinderDirection.

Normals Sphere Center

When Emitter Normals Mode is ENM_Spherical , particle normals are created to face away from Normals Sphere Center . The value is in local space.

Normals Cylinder Direction

When Emitter Normals Mode is ENM_Cylindrical , particle normals are created to face away from the cylinder going through Normals Sphere Center in the direction Normals Cylinder Direction . This value is in local space.

Spawn Module

Every particle emitter contains this module which contains all the properties that determine how particles are spawned. This includes the following:

Property

Description

Spawn

Rate

This float distribution provides the spawn rate (particle per second) of particles for the emitter at a given time.

Rate Scale

A scaling factor to apply to the Rate for the emitter.

Process Spawn Rate

If true , the Rate will be processed. If multiple Spawn Modules are 'stacked' in an emitter and ANY one of them has this property disabled, none of the Rates will be processed for the emitter.

Burst

The Burst data indicates that the emitter should force the emission of a given number of particles at a set time. It involves the following members:

ParticleBurstMethod

The method to use when emitting particles in bursts. Currently ignored.

BurstList

An array of integer Count and CountLow and float Time values identifying desired bursts of particles. Time is in the range of [0..1] over the emitter lifetime. If CountLow is set to -1, the emitter will burst Count particles at the given time. Otherwise, the emitter will burst a random number of particles in the range [CountLow..Count] at the given time.

Process Burst list

If true , the Burst List will be processed. If multiple Spawn Modules are 'stacked' in an emitter and ANY one of them has this property disabled, none of the Burst Lists will be processed for the emitter.

Burst Scale

Scales all burst entries by this amount.

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