AVEVA™ XR Studio

PxParticlesComplex

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PxParticlesComplex

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Last UpdatedDec 16, 2023
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The PxParticlesComplex node derives from PxParticles and inherits all its parameters.

A complex particle system is a particle system made up of 1-n emitters. The particles of a complex particle system can interact with the physical scene but do not interact with each other.

Platform support

This node is supported on XR-Windows platform only.

XR-WIN	XR-P-WIN	XR-P-IOS	XR-P-AND	XR-P-WASM
Full support	No support	No support	No support	No support

shaderType

The PxParticleComplex node supports both prebuilt shaders and generated shaders.

AlphaBlend: The colors of the textures associated to the particles are blended according to their alpha.
AlphaAdd: The colors of the textures associated to the particles are added.
ShaderGen: Based on a selection of shadergen shaders and a blend mode.

Note: ShaderGen shaders are the only shaders supported by ClipPlanes, so they should be the preferred choice.

Soft blending

Soft blending reduces or eliminates hard edges that appear when texture particles intersect other solid meshes.

This setting blends the texture of the solid mesh with the mesh of the texture according to the softScale parameter.

The contribute to the color from the particle texture decreases linearly based on the distance among the pixels of the mesh texture and the one of the particle texture. When the distance is greater than or equal to softscale value, the contribute is null.

Meshcut and killbox

Meshcut limits the rendering of the particles of a system to a limited area. Meshcut uses a list of cmeshes and, depending on the meshcutInside value, only particles inside the cmeshes are rendered.

Use Meshcut, for example, to avoid a gas being rendered outside a pipe that contains it.

Killbox is another way to define where particles are displayed and where they are not. When killbox is enabled, only those particles that are inside the killbox are rendered. The advantage of killbox is that it does not require geometry creation. The disadvantage is that it is a box oriented with the axes and does not always fit.

You can combine the two mechanisms.

Code example

This is a code example for the PxParticlesComplex node.

PxSParticlesComplex fields

These are the fields for PxParticlesComplex node. Only the node-specific fields are indicated, not fields obtained by inheritance.

Field inheritance: NodeBase > NodeBaseMovable > PxParticles > PxParticlesComplex

Fields	Type	Use	Default value	Description
collisionWithDynamicActors	sbool	Optional	false	Enables/disables collision of particles with dynamic actors. Setting this flag makes particles collide with, but not influence rigid bodies. Turn off the flag so the SDK can save memory space and execution time.
contactOffset	sfloat	Optional	0.2	Defines the distance at which contacts between particles and rigid actors are created. The contacts are internally used to avoid jitter and sticking. It must be larger than restOffset.
damping	sfloat	Optional	0	Velocity damping constant, which is globally applied to each particle. It is a force used to reduce the velocity of the particles over time.
disableGravity	sbool	Optional	false	Particles are not influenced by gravity.
disableWind	sbool	Optional	false	Particles are not influenced by wind.
durationLoops	sint	Optional	0	Number of emission loops. Zero (0) means infinite.
durationTime	sfloat	Optional	10	Emission duration for each loop, in seconds.
dynamicFriction	sfloat	Optional	0	Dynamic friction used for collision with the shapes of Dynamic Actors.
emittersNum	sint	Optional	1	Number of emitters in the particle system.
enabled	sbool	Optional	true	Block/unblocks particle system calculations.
externalAcceleration	svec3	Optional	0 0 0	Extra acceleration applied to each particle at each time step.
gridSize	sfloat	Optional	5	Sets the particle grid size used for internal spatial data structures. Aa hint for the PhysX to choose the particle grouping granularity for proximity tests and parallelization. Small grid size values might result in spatial data structure overflow, since the number of grid cells is limited to about 1000. Large grid size values on the other hand might result in poor performance due to ineffective spatial queries or lack of parallelization opportunities.
influenceDynamicActors	sbool	Optional	false	Enables/disables particles influence to the rigid bodies simulation. When false, rigid bodies are not influenced by colliding particles. Use particleMass to control the strength of the feedback force on rigid bodies.
maxMotionDistance	sfloat	Optional	0.3	The maximum distance a particle can travel during one simulation step. High values may hurt performance, while low values may restrict the particle velocity too much.
maxParticles	sint	Optional	5000	The maximum number of particles that can be added to a particle system. It also impacts the memory allocated by the system.
particleMass	sfloat	Optional	0.01	Mass used for two way interaction with rigid bodies.
pxScene	sstring	Mandatory	Not set	Name of the PxScene the particle system belongs to.
rate	sfloat	Optional	200	Emission rate, in particles per second.
recycleParticles	sbool	Optional	false	Sometimes, especially when particles have long life, it may happen the emitter is no longer able to emit new particles due to the fact there are already \\maxParticles emitted particles. Setting the value of this field to true when reached the \\maxParticles value, old particles are killed to let the emitter emit new ones according to the desired rate.
reset	sevent	Optional	Not set	Kills all the living particles, so resets the system.
restitution	sfloat	Optional	0	Restitution used for collision with shapes.
restOffset	sfloat	Optional	0.1	Defines the minimum distance between particles and the surface of rigid actors that the collision system maintains.
shaderGen.blendMode	senum	Optional	alphaBlending	Defines the blend mode to use with the shadergen shader. Values are opaque, additive, alphaAdditive, and alphaBlending.
shaderGen.depthWrite	sbool	Optional	false	Sets the shader to use depthWrite. Having it disabled avoids issues.
shaderGen.shader	sstring	Optional	CodeLib\|Particles\|VcTxt	Specifies the shaderGen shader to use. Even though the selection in XR Studio is restricted to CodeLib\|Particles\|VcTxt,CodeLib\|Particles\|VcTxtSoft the field can be patched with any other shader.
shaderType	senum	Optional	AlphaBlend	Specifies the shader type to use. Values are ShaderGen, AlphaAdd, and AlphaBlend.
skipPassHdrb	sbool	Optional	false	Should be set to true when using realtime shadows to avoid conflicts among particles and shadows visualization. Verify that the rendering effect of the particle system changes.
staticFriction	sfloat	Optional	0	Static friction used for collision with the shapes of Static Actors.
template	sstring	Mandatory	Not set	Name of the template particle system loaded as parameter starting point. It can be set at runtime too to change the particle system settings.
visible	sbool	Optional	true	Shows/hides the particle system.

Emitter attributes

Access the fields of the emitter of a PxParticle with the syntax:

pxparticle.EmitterN\attribute

For example: fuoco.Emitter0\life

MVEC3 fields represents list of parameters with the convention: timekey, minvalue, maxvalue.

Attribute	Type	Use	Default value	Description
aspect	sfloat	Optional	1	Particle's aspect ratio (for example 16:9 is 1.78).
blue	mvec3	Optional	0 10 10	Particle's blue color during the particle's life time.
enabled	sbool	Optional	true	Enables/disables emission of particles.
green	mvec3	Optional	0 30 30	Particle's green color during the particle's life time.
halfEmissionCone	mvec3	Optional	0 10 10	Half of the angle of emission, relative to the untransformed Y axis.
life	mvec3	Optional	0 0.8 1.2	Perturbation of nominal particle duration time.
linkToActorMesh	sstring	Optional	Not set	Links the emitter to a physx dynamic mesh.
localPos	svec3	Read only	Internally calculated	This fields reflects the position of the emitter in World coordinate system.
localRot	svec4	Read only	Internally calculated	This fields reflects the Quaternion rotation of the emitter in World coordinate system.
orientation	svec3	Optional	0 0 0	Returns scene emitter orientation. The three elements of the vector are yaw, pitch, and roll. The values are in radians. Please consider that the emitter is a child of the Node transformation, thus the final space transformation is calculated in the following order: Emitter/orientation * Emitter/position * TransformOffset * Transform * matrix * Parent. In cases where no parent is expressed, the World coordinate system is its parent.
position	svec3	Optional	0 0 0	Local emitter position. Please consider that the emitter is a child of the Node transformation, thus the final space transformation is calculated in the following order: Emitter/orientation * Emitter/position * TransformOffset * Transform * matrix * Parent. In cases where no parent is expressed, the World coordinate system is its parent.
rateMultiplier	mvec3	Optional	0 1 1.2	Perturbation of the nominal particles emission rate.
red	mvec3	Optional	0 200 200	Particle's red color during the particle's life time.
rotation	mvec3	Optional	0 -360 360	Particle's 2D rotation (degrees).
shapeHalfX	sfloat	Optional	0	Emitter half width.
shapeHalfY	sfloat	Optional	0	Emitter half height.
shapeHalfZ	sfloat	Optional	0	Emitter half length.
shapeType	senum	Optional	Rectangle	Shape of the emitter among Point, Rectangle (box) and Cylinder.
size	mvec3	Optional	0 1 1	Size of the rendered particles.
sizeOverLife	mvec3	Optional	0 30 30,22 60 60,45 70 70, 100 40 40	How the size changes during the particle's life time.
spin	mvec3	Optional	0 -360 360	Particle's 2D rotation speed.
spinOverLife			0 60 70,25 100 100,100 0 10	How the spin value changes during the particle's life time.
textureAnimFps	sfloat	Optional	0	The animation's frames per second. 0 means no animation.
textureAnimFrameWidth	sint	Optional	0	Width of the frames inside the texture (used only if textureType is Animated).
textureAnimFrameHeight	sint	Optional	0	Height of the frames inside the texture (used only if textureType is Animated).
textureAnimNumFrames	sint	Optional	0	Number of frames used in the animation (used only if textureType is Animated).
textureAnimRandomStart	sint	Optional	true	Will randomize the first frame the Particle will use when spawned.
textureAnimStartFrame	sint	Optional	0	Initial animation frame (used only if textureType is Animated).
textureName	sstring	Optional	Fire.png	Name of the texture file used by the emitter.
textureType	senum	Optional	Animated	Selects between Simple and Animated textures.
velocity	mvec3	Optional	0 0.5 1.5	Particle velocity on emission.
visibility	mvec3	Optional	0 1 1	Particle's alpha value.
visibilityOverLife	mvec3	Optional	0 25 30,10 75 80,75 75 80,100 0 15	How the alpha value changes during the particle's life time.

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