Particle editor reference

Reference for the Kanzi Studio editor team building a particles editor UI. Enumerates the particle node types, their plugin-defined properties, and (in the Asset package section at the bottom) the data-driven property types and materials shipped in assets/ParticlesAssetPackage/.

Note

Status: stub. The plugin-defined property tables are populated from metadata. Asset-package sections are structural only and will be filled in over time.

The marker-delimited tables on this page are regenerated by docs/tools/generate_particle_editor_reference.py from the plugin metadata and the asset package. Hand-written prose outside the markers is untouched; do not hand-edit the tables.

Conventions

• Plugin-defined property: declared in C++ via the plugin metadata (see assets/ParticlesAssetPackage/Kanzi Engine Plugins/kzparticles.kzm). These are always present on the node and have stable types, defaults, and bounds. Covered in the per-node sections below.

• Asset-package property: declared as a PropertyType in the asset package project. Its value is read by a compute shader whose material is assigned to one of the node’s material slots (EmissionMaterial, AffectorMaterial, ColliderMaterial, GenerateEventsMaterial, etc.). These properties are not auto-added when a material is selected: the author has to set each one on the node explicitly for the value to reach the shader. A good editor UX would hide or show them based on the selected material; today that filtering is the author’s responsibility. Covered in the asset-package section at the bottom.

• Buffer property: a property whose value is a handle to a GPU buffer rather than a plain scalar or vector. Two kinds exist: output buffers the engine writes to on a producing node (ParticleEmitter.EventBuffer, ParticleEmitter.ParticleDataBuffer on a source emitter), and input buffers a consuming node reads from (Emission.SourceEventBuffer, Emission.SourceParticleDataBuffer on a subemitter). The author doesn’t type a value into an input buffer property: it gets populated by a Binding that pulls from the producer and pushes into the consumer. The property still has to be present on the consuming node (even as an empty reference) for the binding to have somewhere to write.

• Asset path: paths like ParticlesAssetPackage/Materials/... are relative to the asset package root.

ParticleSystem

Root of a particle effect. Hosts emitters, affectors, and colliders as children.

Working examples: every Exhibit N/Particle System.kzm under assets/ParticlesAssetPackage/Screens/Screen/RootNode/Viewport 2D/Scene/.

Plugin-defined properties

Property	Type	Default	Range	Category	Description
ParticleSystem.Framerate	Float	60.0	0.5 .. 60.0 (step 1.0)	Particle System	Number of simulation steps per second. Higher values improve accuracy at increased CPU cost.
ParticleSystem.IntegrationMethod	Enum: Euler, Verlet	Verlet	—	Particle System	Selects the integration method for particle position updates. Verlet provides improved energy conservation; Euler is the classical method. The prevPosition field is populated every frame regardless of which integrator is active.
ParticleSystem.SortingCameraOverride	String	—	—	Particle System	Optional. Path to a Camera node to use for sort key computation. If empty, uses the Scene’s default camera.

Children

• ParticleEmitter (one or more)

• ParticleAffector (zero or more)

• ParticleCollider (zero or more)

• Nested ParticleSystem or grouping EmptyNode (for subemitter setups: see Exhibit 6)

ParticleEmitter

Spawns and renders particles. Behaviour is almost entirely determined by the materials assigned to its material slots; those materials drive the asset-package properties documented in the asset-package section.

Working examples:

• Simple fountain: Screens/.../Exhibit 1/Particle System/Fountain.kzm.

• Volume emitters: Screens/.../Exhibit 2/Particle System/*.kzm.

• Subemitter (event-driven): Screens/.../Exhibit 6/Particle System/*/Subemitter.kzm.

Plugin-defined properties

Property	Type	Default	Range	Category	Description
ParticleEmitter.SelfAffectMaterial	ResourceID (Material)	—	—	Affector	Compute material run over all active particles each frame, before integration. Use to implement per-emitter forces, attraction, or custom particle-particle interaction.
ParticleEmitter.EmissionCountMaterial	ResourceID (Material)	—	—	Emission	Emission count material. Single-invocation compute shader that implements uint EmissionCount() and writes the workgroup count to the indirect emit buffer. Use EmissionCount_Schedule from the ParticlesAssetPackage for time-based emission, EmissionCount_FromEvents to emit from an event buffer, or a custom shader.
ParticleEmitter.EmissionMaterial	ResourceID (Material)	—	—	Emission	Compute material that implements EmitParticle(). Defines the spawn position, velocity, and initial state of each new particle.
ParticleEmitter.MaximumAmount	Int	5000	0 .. 2000000 (step 10)	Emission	Maximum amount of particles for this emitter. [1]
ParticleEmitter.EventBuffer	ResourceID (Buffer)	—	—	Events	GPU buffer populated by the Event Generate Material. Read-only; automatically allocated and updated by the emitter. [2]
ParticleEmitter.GenerateEventsMaterial	ResourceID (Material)	—	—	Events	Event generation material. Compute shader that writes events (e.g. death events) to the EventBuffer.
ParticleEmitter.ParticleDataBuffer	ResourceID (Buffer)	—	—	Events	GPU buffer holding all particle state for this emitter. Read-only; bind this to a sub-emitter’s emission shader to access source particle positions. [2]
ParticleEmitter.ParticleMaterial	ResourceID (Material)	—	—	Rendering	2D/3D particle material. This defines the look and behavior of the particles.
ParticleEmitter.ParticleMesh	ResourceID (Mesh)	—	—	Rendering	Optional mesh rendered once per particle. Leave unset to render camera-facing 2D billboards using the default 2D particle material.
ParticleEmitter.SortingType	Enum: Identity, Depth, Reverse Depth, Unsorted	Identity	—	Rendering	Controls particle draw order. Identity: default, allocates index buffer with identity mapping, no per-frame cost. Depth: back-to-front GPU sort for transparent particles. Reverse Depth: front-to-back sort for opaque particles. Unsorted: no index buffer, saves memory, material must not reference SortingIndicesBuffer.

[1]

It’s often convenient to bind MaximumAmount to an expression derived from the chosen emission-count material’s parameters so the cap scales with the rate or burst settings. See the emission-count materials in the asset-package section for recommended binding expressions per material.

[2] (1,2)

These output buffers feed subemitter inputs: ParticleDataBuffer → Emission.SourceParticleDataBuffer, EventBuffer → Emission.SourceEventBuffer. See GPU buffer binding reference (for subemitters) for the full wiring.

ParticleAffector

Applies a per-frame force or transformation to all particles in the system.

Working examples: Screens/.../Exhibit 1/Particle System/Gravity.kzm and Exhibit 3/*/Particle Affector.kzm.

Plugin-defined properties

Property	Type	Default	Range	Category	Description
ParticleAffector.AffectorMaterial	ResourceID (Material)	—	—	Affector	Affector material. Should contain only specific compute shader that is used to affect particles.

ParticleCollider

Defines a collision volume that particles interact with after integration.

Working examples: Screens/.../Exhibit 1/Particle System/Box Collider.kzm and all collider shapes in Screens/.../Exhibit 5/Particle System/<Shape>/Bounce.kzm and Floor.kzm.

Plugin-defined properties

Property	Type	Default	Range	Category	Description
ParticleCollider.Bounce	Float	0.5	0.0 .. 1.0 (step 0.01)	Collider	Coefficient of restitution [0..1]. 0 = inelastic (no bounce), 1 = perfectly elastic.
ParticleCollider.ColliderMaterial	ResourceID (Material)	—	—	Collider	Collider material. Must contain a compute shader that includes Particles/collider.glsl and implements HitInfo Collide(mat4, vec3, vec3).
ParticleCollider.Friction	Float	0.1	0.0 .. 1.0 (step 0.01)	Collider	Tangential velocity damping factor [0..1]. 0 = no friction, 1 = full stop along surface.

Asset package

Everything below this line is shipped as editable content in assets/ParticlesAssetPackage/, not compiled into the plugin. It can be modified, replaced, or extended per project. These are the property types and materials that drive the per-slot behaviour of the nodes above.

Property types

Defined under assets/ParticlesAssetPackage/PropertyTypes/. Each property’s default, min, max, category, and tooltip is declared on the property type asset.

Emission

Property	Type	Default	Min	Max	Category	Tooltip
Emission.AmountPerSecond	Float	10	0	50000	Emission	—
Emission.BoxExtents	Vector3DDynamicPropertyType	0.5,0.5,0.5	0,0,0	100,100,100	Emission	—
Emission.BurstCount	Float	0	0	1	Emission	—
Emission.BurstInterval	Float	0	0	1	Emission	—
Emission.Density	Float	1	0	100	Emission	—
Emission.EmitAlongNormal	Bool	false	—	—	Emission	—
Emission.ImpulseAtCycleStart	Float	0	0	100000	Emission	Particles emitted in a single burst at the start of each cycle. Float to preserve the fractional accumulator tail.
Emission.ImpulseVariance	Float	0	0	100000	Emission	Symmetric +/- variance band on ImpulseAtCycleStart, rolled once per cycle.
Emission.IndexCount	Int	0	-2147483648	2147483647	Emission	—
Emission.Indices	Buffer ref	—	—	—	Emission	—
Emission.InitialAngularVelocity	Vector3DDynamicPropertyType	0,0,0	-62.8318558,-62.8318558,-62.8318558	62.8318558,62.8318558,62.8318558	Emission	—
Emission.InitialAngularVelocityFromParent	Float	0	0	1	Emission	Weight applied to the parent particle’s angular velocity, added to the locally-sampled initial angular velocity. 0 = pure local; 1 = parent angular velocity added on top of local. To inherit the parent’s angular velocity verbatim, also set Emission.InitialAngularVelocity to (0,0,0). Only meaningful on emitters with a bound source-particle buffer (Emitter_FromEvents).
Emission.InitialAngularVelocityVariance	Vector3DDynamicPropertyType	0,0,0	0,0,0	100,100,100	Emission	—
Emission.InitialForce	Float	1	0	100	Emission	—
Emission.InitialRotation	Vector3DDynamicPropertyType	0,0,0	-6.28318548,-6.28318548,-6.28318548	6.28318548,6.28318548,6.28318548	Emission	—
Emission.InitialRotationFromParent	Float	0	0	1	Emission	Weight applied to the parent particle’s rotation, added to the locally-sampled initial rotation. 0 = pure local; 1 = parent rotation added on top of local. To inherit the parent’s rotation verbatim, also set Emission.InitialRotation to (0,0,0). Only meaningful on emitters with a bound source-particle buffer (Emitter_FromEvents).
Emission.InitialRotationVariance	Vector3DDynamicPropertyType	0,0,0	0,0,0	100,100,100	Emission	—
Emission.InitialSpeed	Float	4	0	20	Emission	—
Emission.InitialSpeedVariance	Float	1	0	10	Emission	—
Emission.InitialVelocityDirection	Vector3DDynamicPropertyType	0,0,1	-1,-1,-1	1,1,1	Emission	—
Emission.InitialVelocityInnerAngle	Float	0	0	3.14159274	Emission	—
Emission.InitialVelocityOrientToNormal	Bool	true	—	—	Emission	When true, the velocity cone is built around the spawn context’s natural normal instead of around InitialVelocityDirection. On a surface emitter the normal is the spawn surface normal (ignored when Volume = true). On Emitter_FromEvents the normal is the parent particle’s velocity vector, so children fan out around the direction the parent was moving.
Emission.InitialVelocityOuterAngle	Float	3.14159274	0	3.14159274	Emission	—
Emission.InitialVelocityStrength	Float	1	0	100	Emission	—
Emission.InitialVelocityStrengthFromParent	Float	0	0	1	Emission	Weight applied to the parent particle’s speed (length of its velocity vector), added to the locally-sampled initial speed. Direction always comes from the cone sample (InitialVelocityDirection or OrientToNormal), so this lets a child inherit how fast the parent was moving without inheriting which way. 0 = pure local speed; 1 = parent speed added on top of local. To inherit the parent’s speed verbatim, also set Emission.InitialVelocityStrength to 0. Only meaningful on emitters with a bound source-particle buffer (Emitter_FromEvents).
Emission.InitialVelocityStrengthVariance	Float	0	0	100	Emission	—
Emission.InnerConeAngle	Float	15	0	90	Emission	—
Emission.InnerRadius	Float	0	0	1	Emission	—
Emission.LateralSpread	Float	0	0	10	Emission	—
Emission.Lifetime	Float	1	0	10	Emission	—
Emission.LifetimeFromParent	Float	0	0	1	Emission	Weight applied to the parent particle’s total lifetime, added to the locally-sampled lifetime. 0 = pure local; 1 = parent lifetime added on top of local. To inherit the parent’s lifetime verbatim, also set Emission.Lifetime to 0. Only meaningful on emitters with a bound source-particle buffer (Emitter_FromEvents).
Emission.LifetimeVariance	Float	0	0	5	Emission	—
Emission.MajorRadius	Float	1	0	1	Emission	—
Emission.Mask	Buffer ref	—	—	—	Emission	—
Emission.MaskThreshold	Float	0.5	0	1	Emission	—
Emission.Mesh	Buffer ref	—	—	—	Emission	—
Emission.MinorRadius	Float	0.25	0	1	Emission	—
Emission.NormalBias	Float	0.300000012	0	1	Emission	Pulls spark scatter direction toward the surface normal. 0 = full hemisphere, 1 = along normal only.
Emission.Normals	Buffer ref	—	—	—	Emission	—
Emission.OffDuration	Float	0	0	1	Emission	—
Emission.OnDuration	Float	0	0	1	Emission	—
Emission.OuterConeAngle	Float	45	0	90	Emission	—
Emission.OuterRadius	Float	1	0	10	Emission	—
Emission.ParticleScale	Float	0.0500000007	0.00999999978	2	Emission	—
Emission.ParticlesPerEvent	Int	1	1	100	Emission	—
Emission.Positions	Buffer ref	—	—	—	Emission	—
Emission.Radius	Float	1	0.100000001	100	Emission	—
Emission.Rate	Float	10	0	50000	Emission	Particles per second emitted during the cycle on-phase.
Emission.RateVariance	Float	0	0	50000	Emission	Symmetric +/- variance band on Rate, rolled once per frame.
Emission.RiseSpeed	Float	2	0	20	Emission	—
Emission.Scale	Vector3DDynamicPropertyType	1,1,1	0,0,0	100,100,100	Emission	—
Emission.ScaleFromParent	Float	0	0	1	Emission	Multiplicative scale inheritance from the parent particle (per-axis lerp on the factor). 0 = pure local scale. 1 = local scale multiplied by the parent’s scale, so with the Emission.Scale default of (1, 1, 1) the child matches the parent’s scale exactly. In between, the parent contributes proportionally. Only meaningful on emitters with a bound source-particle buffer (Emitter_FromEvents).
Emission.ScaleVariance	Vector3DDynamicPropertyType	0,0,0	0,0,0	100,100,100	Emission	—
Emission.ScatterSpeed	Float	5	0	50	Emission	Base speed of spark particles scattered from a hit event.
Emission.Seed	Float	0	0	100000	Emission	Seed for the Rate/Impulse variance RNG. Two emitters with the same Seed produce identical, repeatable sequences; change it to decorrelate emitters.
Emission.SourceEventBuffer	Buffer ref	—	—	—	Emission	—
Emission.SourceParticleDataBuffer	Buffer ref	—	—	—	Emission	Buffer holding the source emitter’s particle data, used by subemitters to read source particle state at event time.
Emission.SpreadSpeed	Float	1	0	20	Emission	—
Emission.UVs	Buffer ref	—	—	—	Emission	—
Emission.UseMask	Bool	false	—	—	Emission	—
Emission.Volume	Bool	false	—	—	Emission	—

Affector

Property	Type	Default	Min	Max	Category	Tooltip
Affector.BuoyancyFalloff	Float	1	0.100000001	5	Affector	—
Affector.DilationFactor	Float	0.5	0	4	Affector	Per-particle time scale applied at the centre of the sphere. Below 1 slows particles down (0 freezes them); above 1 speeds them up. The falloff curve blends back to 1 at the sphere surface.
Affector.Direction	Vector3DDynamicPropertyType	0,1,0	-1,-1,-1	1,1,1	Affector	Acceleration direction in the affector node’s local frame. Normalised in the shader; a zero vector is treated as the local +Y axis.
Affector.DirectionalStrength	Float	0	0	15	Affector	—
Affector.DragCoefficient	Float	0	0	1	Affector	—
Affector.DragFactor	Float	1	0	10	Affector	How strongly the medium resists particle motion. Describes the medium, not the wind. 0.5 = thin air, 1.0 = sea-level air, 3+ = dense/humid, 5+ = underwater.
Affector.FalloffExponent	Float	0	-1	1	Affector	Shapes the sphere-of-influence falloff curve. 0 is a linear ramp; negative drops off rapidly near the centre then tapers; positive stays near full strength then falls sharply at the edge. ~1 approximates a hard cutoff at the radius. Only used when Radius > 0.
Affector.FalloffRadius	Float	0	0	1	Affector	—
Affector.Frequency	Float	0	0	1	Affector	—
Affector.FullWindHeight	Float	5	0	50	Affector	World-space Y height where wind reaches full strength. Between GroundLevel and this height, wind ramps up smoothly (smoothstep).
Affector.GroundLevel	Float	0	-10	10	Affector	World-space Y height where wind starts. Below this height, wind strength is zero. Used with FullWindHeight to create a height-based wind gradient.
Affector.GustAmplitude	Float	0.300000012	0	1	Affector	Strength of wind gusts as a fraction of WindSpeed. 0 = steady wind, 0.3 = gusts up to 30% stronger/weaker, 1.0 = gusts can double the wind or drop to zero.
Affector.GustFrequency	Float	2	0	20	Affector	Spatial frequency of wind gusts. Higher values create more rapid variation as particles move through the wind field.
Affector.Magnitude	Float	1	-100	100	Affector	Signed acceleration magnitude along the normalised Direction. Negative values decelerate (push opposite the direction); animating through zero sweeps smoothly between the two.
Affector.MaxBuoyancy	Float	18	0	50	Affector	—
Affector.MaxSpeed	Float	0	0	1	Affector	—
Affector.Radius	Float	0	0	100	Affector	—
Affector.Strength	Float	0	0	10	Affector	—
Affector.TimeScale	Float	0	0	1	Affector	—
Affector.TurbulenceFrequency	Float	5	0	20	Affector	—
Affector.TurbulenceStrength	Float	3	0	20	Affector	—
Affector.WindSpeed	Float	10	0	150	Affector	Wind speed in km/h along the affector’s local Z axis. 10 = light breeze, 40 = strong wind, 100+ = storm.

Collider

Property	Type	Default	Min	Max	Category	Tooltip
Collider.Angle	Float	30	1	89	Collider	Half-angle of the cone collider in degrees. 0 is a line, 90 would be a flat disc.
Collider.DamageThreshold	Int	0	-2147483648	2147483647	Collider	—
Collider.Height	Float	2	0	50	Collider	Height of the collider shape along its local Y axis.
Collider.KeepInside	Int	0	0	1	Collider	Confinement mode. 0 (default): particles outside the volume pass freely and particles entering bounce off the inner-facing surface. 1: predicate and surface normal invert — particles inside the volume pass freely and particles trying to leave bounce off the outer-facing surface. For Collider_Plane this is a half-space flip (same plane geometry, opposite half is now the “outside”). Declared as int rather than bool because the plugin’s UBO push for bool members has a known size mismatch — see RENDERING-2882.
Collider.Radius	Float	0	0	100	Collider	—

Events

Property	Type	Default	Min	Max	Category	Tooltip
Events.AccelerationMax	Float	1E+10	0	1E+10	Events	Upper bound of the acceleration-magnitude band (plugin acceleration units) within which events fire. The very large default effectively means “no upper bound”.
Events.AccelerationMin	Float	0	0	100	Events	Lower bound of the acceleration-magnitude band (plugin acceleration units) within which events fire. Snapshot test, evaluated each frame.
Events.AgeMax	Float	1E+10	0	1E+10	Events	Upper bound (seconds) of the absolute-age band the particle’s per-frame age sweep must overlap for an event to fire. The very large default effectively means “no upper bound”.
Events.AgeMin	Float	0	0	100	Events	Lower bound (seconds) of the absolute-age band the particle’s per-frame age sweep must overlap for an event to fire.
Events.Interval	Float	1	0	60	Events	Seconds between periodic events, per particle. Phase is anchored at each particle’s birth, so staggered particles produce a steady population-level stream.
Events.LifetimeMax	Float	1	0	1	Events	Upper bound of the normalised particle lifetime (0-1) band during which events fire. Min = Max = 1 fires on death; Min = Max = 0 fires on birth.
Events.LifetimeMin	Float	1	0	1	Events	Lower bound of the normalised particle lifetime (0-1) band during which events fire. Min = Max = 1 fires on death; Min = Max = 0 fires on birth.
Events.Probability	Float	1	0	1	Events	Population-level fire probability. Per-particle deterministic (rolled against the particle hash), so a fixed fraction of the population fires rather than a per-frame coin flip. 1 = every qualifying particle fires.
Events.VelocityMax	Float	1E+10	0	1E+10	Events	Upper bound of the speed band the particle’s per-frame speed sweep must overlap for an event to fire. The very large default effectively means “no upper bound”.
Events.VelocityMin	Float	0	0	100	Events	Lower bound of the speed band the particle’s per-frame speed sweep must overlap for an event to fire.

Particle rendering

Used by the particle-rendering materials under the ParticleMaterial slot.

Property	Category	Used by
ParticlesOverLife.ColorStart, ParticlesOverLife.ColorEnd	Color	ParticlesColorOverLife, ParticlesColorOverLife_Green, ParticlesColorOverLife_Red
ParticlesOverLife.ScaleStart, ParticlesOverLife.ScaleEnd	Scale	All ParticlesColorOverLife* variants
ParticlesOverLife.OpacityStart, ParticlesOverLife.OpacityEnd	Opacity	All ParticlesColorOverLife* variants
ParticlesOverLife.ColorMid, ParticlesOverLife.ColorMidPoint	Color (3-stop)	ParticlesColorOverLife3Stop
ParticlesOverLife.ScaleMid, ParticlesOverLife.ScaleMidPoint	Scale (3-stop)	ParticlesColorOverLife3Stop
ParticlesOverLife.OpacityMid, ParticlesOverLife.OpacityMidPoint	Opacity (3-stop)	ParticlesColorOverLife3Stop
FastColor, SlowColor, FastScale, SlowScale, SpeedThreshold, SpeedVariance, MaxDisplaySpeed	Velocity	ParticlesVelocityColor

Non-particle rendering (environment)

These drive the WorldGrid / Glass materials used in the exhibit scenery and aren’t particle-specific.

Property	Used by
WorldGrid.BaseColor, WorldGrid.BaseMetallic, WorldGrid.BaseRoughness, WorldGrid.GridColor, WorldGrid.GridMetallic, WorldGrid.GridRoughness, WorldGrid.GridSpacing, WorldGrid.GridWidth	WorldGridPBR
MaterialGlass.CubemapColor, MaterialGlass.Falloff, MaterialGlass.TextureCube	Glass Material

Materials

Defined under assets/ParticlesAssetPackage/Materials/ (material instances) and assets/ParticlesAssetPackage/Material Types/ (material types, which declare the shader and uniforms). Each table lists materials grouped by the node material-slot they’re designed for, and which asset-package properties the material consumes.

Emission materials (→ ParticleEmitter.EmissionMaterial)

Material	Role	Properties used
Emitter_Box	Spawn on the faces of a box (or inside it with Emission.Volume).	Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialVelocityOrientToNormal, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density, Emission.BoxExtents, Emission.Volume
Emitter_Disc	Spawn on the rims of an annular disc (or across its area with Emission.Volume).	Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialVelocityOrientToNormal, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density, Emission.OuterRadius, Emission.InnerRadius, Emission.Volume
Emitter_Embers	Fire-effect embers: spawn in a disc on the XZ plane and rise. Not in the Asset Packages browser.	Emission.Lifetime, Emission.LifetimeVariance, Emission.Radius, Emission.InitialSpeed, Emission.InitialSpeedVariance, Emission.ParticleScale
Emitter_Fire	Fire-effect flames: spawn in a disc on the XZ plane and rise with lateral spread.	Emission.Lifetime, Emission.LifetimeVariance, Emission.InitialSpeed, Emission.InitialSpeedVariance, Emission.ParticleScale, Emission.LateralSpread, Emission.Radius
Emitter_FromEvents	Subemitter spawn: one particle per event from bound event buffer.	Emission.SourceEventBuffer, Emission.SourceParticleDataBuffer, Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density, Emission.InitialVelocityStrengthFromParent, Emission.LifetimeFromParent, Emission.ScaleFromParent, Emission.InitialRotationFromParent, Emission.InitialAngularVelocityFromParent, Emission.InitialVelocityOrientToNormal, Emission.ParticlesPerEvent
Emitter_MeshEdges	Spawn along the triangle edges of a mesh.	Emission.Lifetime, Emission.InitialSpeed, Emission.EmitAlongNormal, Emission.IndexCount, Emission.Positions, Emission.Normals, Emission.Indices, Scale
Emitter_MeshSurface	Spawn on the triangles of a mesh.	Emission.Lifetime, Emission.InitialSpeed, Emission.EmitAlongNormal, Emission.IndexCount, Emission.Positions, Emission.Normals, Emission.Indices, Scale
Emitter_MeshVertices	Spawn at the vertices of a mesh.	Emission.Lifetime, Emission.InitialSpeed, Emission.EmitAlongNormal, Emission.IndexCount, Emission.Positions, Emission.Normals, Scale
Emitter_Point	Spawn at the emitter origin; cone or fountain through the velocity angles.	Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialVelocityOrientToNormal, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density
Emitter_Smoke_FromEvents	Subemitter spawn for smoke: slow upward drift with lateral spread. Not in the Asset Packages browser.	Emission.SourceEventBuffer, Emission.SourceParticleDataBuffer, Emission.Lifetime, Emission.LifetimeVariance, Emission.ParticleScale, Emission.RiseSpeed, Emission.SpreadSpeed, ScaleVariance
Emitter_Sparks_FromHit	Event-driven spark spawn triggered by hit events. Not in the Asset Packages browser.	Emission.SourceEventBuffer, Emission.SourceParticleDataBuffer, Emission.Lifetime, Emission.LifetimeVariance, Emission.ParticleScale, Emission.ScatterSpeed, Emission.NormalBias, ScaleVariance
Emitter_Sphere	Spawn on a sphere shell (or inside it with Emission.Volume).	Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialVelocityOrientToNormal, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density, Emission.Volume, Emission.Radius
Emitter_Torus	Spawn on the skin of a torus tube (or inside the tube with Emission.Volume).	Emission.Lifetime, Emission.LifetimeVariance, Emission.Scale, Emission.ScaleVariance, Emission.InitialVelocityStrength, Emission.InitialVelocityStrengthVariance, Emission.InitialVelocityDirection, Emission.InitialVelocityInnerAngle, Emission.InitialVelocityOuterAngle, Emission.InitialVelocityOrientToNormal, Emission.InitialRotation, Emission.InitialRotationVariance, Emission.InitialAngularVelocity, Emission.InitialAngularVelocityVariance, Emission.Density, Emission.MajorRadius, Emission.MinorRadius, Emission.Volume

Emission-count materials (→ ParticleEmitter.EmissionCountMaterial)

Each material’s row includes a MaximumAmount binding column with the suggested expression for ParticleEmitter.MaximumAmount. These are heuristics that keep the cap just above steady-state load; authors can override when they want a harder or looser cap.

Material	Role	Properties used	MaximumAmount binding
EmissionCount_FromEvents	Spawn N particles per event from the source emitter.	Emission.SourceEventBuffer, Emission.ParticlesPerEvent	Depends on the source emitter’s event rate; SourceEmitter.MaximumAmount * Emission.ParticlesPerEvent is an upper bound
EmissionCount_Schedule	Time-based emission: steady stream, periodic stream, or bursts.	Emission.Rate, Emission.RateVariance, Emission.OnDuration, Emission.OffDuration, Emission.ImpulseAtCycleStart, Emission.ImpulseVariance, Emission.Seed	Steady stream: ({./Emission.Lifetime} + {./Emission.LifetimeVariance}) * ({./Emission.Rate} + {./Emission.RateVariance}). For bursts see Sizing MaximumAmount

Affector materials (→ ParticleAffector.AffectorMaterial)

Material	Role	Properties used
Affector_Accelerate	Constant acceleration along a direction, with an optional sphere of influence.	Affector.Direction, Affector.Magnitude, Affector.Radius, Affector.FalloffExponent
Affector_Buoyancy	Upward force with turbulence (smoke).	Affector.MaxBuoyancy, Affector.BuoyancyFalloff, Affector.TurbulenceStrength, Affector.TurbulenceFrequency
Affector_CurlNoise	Curl-noise field.	Affector.Frequency, Affector.TimeScale, Affector.Strength, Affector.Radius, Affector.FalloffExponent
Affector_Directional	Directional force.	Affector.DirectionalStrength, Affector.Radius, Affector.FalloffExponent
Affector_Drag	Velocity damping.	Affector.DragCoefficient, Affector.Radius, Affector.FalloffExponent
Affector_Gravity	Constant downward acceleration.	—
Affector_KillZone	Kill particles inside/outside a region.	Affector.Radius, Affector.FalloffExponent
Affector_PointAttractor	Attractor toward a point.	Affector.Strength, Affector.Radius, Affector.FalloffExponent
Affector_TimeDilation	Scale local dt.	Affector.DilationFactor, Affector.Radius, Affector.FalloffExponent
Affector_VelocityClamp	Clamp speed.	Affector.MaxSpeed, Affector.Radius
Affector_Wind	Wind with gusts and height falloff.	Affector.WindSpeed, Affector.DragFactor, Affector.TurbulenceStrength, Affector.TurbulenceFrequency, Affector.GroundLevel, Affector.FullWindHeight, Affector.GustFrequency, Affector.GustAmplitude

Collider materials (→ ParticleCollider.ColliderMaterial)

Material	Role	Properties used
Collider_Box	Axis-aligned box collision (uses node scale).	Collider.KeepInside
Collider_Capsule	Capsule collision.	Collider.Radius, Collider.Height, Collider.KeepInside
Collider_Cone	Cone collision.	Collider.Angle, Collider.Height, Collider.KeepInside
Collider_Cylinder	Cylinder collision.	Collider.Radius, Collider.Height, Collider.KeepInside
Collider_DestructibleBox	Box collision whose cells break after Collider.DamageThreshold hits.	Collider.DamageThreshold
Collider_Plane	Infinite plane collision.	Collider.KeepInside
Collider_Sphere	Sphere collision.	Collider.Radius, Collider.KeepInside

Event-generator materials (→ ParticleEmitter.GenerateEventsMaterial)

Material	Role	Properties used
Event_AccelerationRange	Fires while the acceleration magnitude is within a range.	Events.AccelerationMin, Events.AccelerationMax, Events.Probability
Event_AgeRange	Fires on absolute-age band crossing (seconds, not normalised lifetime).	Events.AgeMin, Events.AgeMax, Events.Probability
Event_Lifetime	Fires on normalised-lifetime band crossing.	Events.LifetimeMin, Events.LifetimeMax, Events.Probability
Event_OnHit	Fires on collision hit; optional speed-range and probability gates.	Events.Probability, Events.VelocityMin, Events.VelocityMax
Event_Periodic	Fires once per interval, per particle, phase-anchored at birth.	Events.Interval, Events.Probability
Event_VelocityRange	Fires on speed-band crossing (symmetric, swept test).	Events.VelocityMin, Events.VelocityMax, Events.Probability

Particle-rendering materials (→ ParticleEmitter.ParticleMaterial)

Material	Role	Properties used
Particles	Default 2D particle material. Not in the Asset Packages browser.	—
Particles_Embers	Ember rendering for the Fire and Smoke exhibit. Not in the Asset Packages browser.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart
Particles_Fire	Flame rendering for the Fire and Smoke exhibit.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart
ParticlesColorOverLife	2-stop color/scale/opacity ramp over lifetime.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart
ParticlesColorOverLife3Stop	3-stop color/scale/opacity ramp with independent midpoints.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorMid, ParticlesOverLife.ColorMidPoint, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityMid, ParticlesOverLife.OpacityMidPoint, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleMid, ParticlesOverLife.ScaleMidPoint, ParticlesOverLife.ScaleStart
ParticlesColorOverLife_Green	Pre-configured green colour ramp instance of ParticlesColorOverLife.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart
ParticlesColorOverLife_Red	Pre-configured red colour ramp instance of ParticlesColorOverLife.	ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart
ParticlesSmoke	Soft, noisy smoke puffs (tuned for the Fire and Smoke exhibit). Not in the Asset Packages browser.	NoiseScale, ParticlesOverLife.ColorEnd, ParticlesOverLife.ColorStart, ParticlesOverLife.EdgeSoftness, ParticlesOverLife.OpacityEnd, ParticlesOverLife.OpacityStart, ParticlesOverLife.ScaleEnd, ParticlesOverLife.ScaleStart, SmokeColor
ParticlesVelocityColor	Color/scale driven by speed.	FastColor, FastScale, InvertBlend, SlowColor, SlowScale, SpeedThreshold, SpeedVariance

Open sections (to flesh out later)

• Value ranges, units, and defaults for every asset-package property (Emission, Affector, Collider, Events, rendering).

• Per-material exact property list: the compute material tables list the property types each material type declares, which can differ from the uniforms its shader reads. The rendering material table lists only properties that the shaders declare as uniforms.

• Per-EmissionMaterial matrix: which shape or motion properties surface for each emitter.

• Event-generator catalog: what each Event_* material emits and which accessor functions it uses.

• Binding recipes: step-by-step for wiring a subemitter (source → subemitter event + particle-data buffers).

• Recommended editor UX: grouping, conditional visibility based on selected material.

GPU buffer binding reference (for subemitters)

This section is called out explicitly because it is the single most opaque part of authoring a subemitter. Per editor-team feedback, it’s the first thing that needs a concrete answer.

Note

The property names below are shader-defined, not hard-coded. Emission.SourceEventBuffer and Emission.SourceParticleDataBuffer are the conventional names used by the shipped Emitter_FromEvents and EmissionCount_FromEvents materials because those shaders declare uniforms with those names. A custom emission or emission-count material can declare uniforms with any names it wants: in which case the subemitter has to carry those property names and the binding targets change accordingly. In other words: the binding wires a producer property (always ParticleEmitter.EventBuffer / ParticleEmitter.ParticleDataBuffer, defined by the plugin) to a consumer property whose name is chosen by whatever compute shader is reading the buffer.

What you’re wiring

A subemitter reads two buffers produced by its source emitter. Using the conventional names from the stock materials:

Subemitter target property	Source emitter property	Purpose
Emission.SourceEventBuffer	ParticleEmitter.EventBuffer	Per-event records the source wrote via its GenerateEventsMaterial.
Emission.SourceParticleDataBuffer	ParticleEmitter.ParticleDataBuffer	Source emitter’s live particle data, so the subemitter can read origin particle state per event.

Each wire is a BindingItem child on the subemitter node with one BindingSourceItem underneath.

Concrete one-liner (target expression)

In a sibling layout where Source and Subemitter share a parent, the target-side expression (BindingItem.DisplayCodeForMerge) is:

{@../Source/ParticleEmitter.EventBuffer}

and:

{@../Source/ParticleEmitter.ParticleDataBuffer}

The BindingItem.RawCode is simply {0} (it references the first and only BindingSourceItem).

Working reference: assets/ParticlesAssetPackage/Screens/Screen/RootNode/Viewport 2D/Scene/Exhibit 6/Particle System/On Hit/Subemitter.kzm: binds to a sibling named Source.

Required BindingItem shape

Each binding needs all of:

• BindingItem.Target → the shader-declared consumer property (e.g. Emission.SourceEventBuffer / Emission.SourceParticleDataBuffer for stock materials), PropertyTypeReference, WHOLE_PROPERTY.

• BindingItem.BindingMode = ONE_WAY.

• BindingItem.PushTarget → the subemitter itself (absolute ProjectItemPath to this node). This is load-bearing: without the push target the buffer handle never arrives at the GPU-side property.

• BindingItem.IsBindingEnabled = true.

• One BindingSourceItem child named "0" whose BindingSourceItem.Item points to the source emitter (absolute path) and whose BindingSourceItem.Source is the PropertyTypeReference ParticleEmitter.EventBuffer / ParticleEmitter.ParticleDataBuffer.

Gotchas

• The buffer-typed consumer property still has to be declared on the node. The shader-declared property (e.g. Emission.SourceEventBuffer) must be present as an empty ProjectItemReference on the subemitter node even though the value comes from the binding. If you omit the literal property the binding has nothing to write into.

• ``PushTarget`` must reference the subemitter itself, not the source. The binding pulls from Source and pushes into Subemitter.

• The subemitter needs ``EmissionMaterial`` = ``Emitter_FromEvents`` and EmissionCountMaterial = EmissionCount_FromEvents (or custom materials declaring the matching consumer properties), otherwise the bound buffers are never consumed.

• ``ParticleMaterial`` is required on the subemitter. Without it the emitter spawns invisible particles; easy to misread as “subemitter not firing”.

• Absolute paths in BindingSourceItem.Item and BindingItem.PushTarget are resolved via ProjectItemPath, so moving or renaming either node invalidates the binding: the editor should rewrite these paths on rename.