Method #
Particle nodes are nodes used in a particles system. This system starts with a Particle Root Node, and is built out with Emitter, Affector and Shader nodes, before finally being rendered to the camera with a Renderer node.
The Particle Root Node contains the particles themselves: their positions, velocities, colours and so on, in a pool waiting to be used. The number of particles in the pool is set by the Max Particle Count attribute on the root node. Particle Emitters take particles from the pool and bring them to life. Particle Affectors make them move; Particle Rendering Nodes control how particles are rendered to screen. When particles die they are returned to the pool until they are emitted again. It is possible that not all the particles in the pool are alive at any time. Even particles that are not currently alive in the pool carry some performance and memory overhead, so it is recommended that the maximum number of particles on the Particle Root node is limited to the amount actually needed by the emitters.
Multiple Particle Emitters may exist under one Particle Root node. Particle Affectors and Rendering nodes may be connected to the Particle Root directly, making them work on every particle under the root node; or they may be connected to individual Emitters, making them only affect the particles emitted by that Emitter.
Particles are generally hooked into the Root node, although they can be applied to any node - they will still appear in the scene as long as there is a path to a Root node.
Aside from the Particle Bounding Box, Particle Event and Particle Root, these nodes are split into 4 groups:
- Affectors, these affect the movement of the particles once they are emitted.
- Emitters, these emit particles based on different shapes or models.
- Rendering, render particles as different shapes or objects.
- Shading, change the colours of the particles based on various parameters.
Affectors
Particle Affector nodes modify particle motion.
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Simulate Cloth with a Particle Mesh Deformer.
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Allows Particles to collide with Meshes.
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Applies curl noise velocities to Particles.
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Allows particles to collide with depth camera data.
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Applies an explosive force to particles at birth.
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Allows particles to be affector by froces from a field.
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Simulates flocking behaviour with particles.
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Simulates fluid dynamics on Particles with FLIP simulations.
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Applies a force to particles.
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Attract or repel particles from an image.
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Remove particles from inside or outside a zone.
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Attract or repel particles from a mesh.
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Apply forces to particles from mesh surfaces.
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Uses points sources to disturb the particles.
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Apply forces to particles from primitive shapes.
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Allows particle collisions with simple 3D primitives.
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Allows particles to interact with procedurals.
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Allows particle collisions with active rigid bodies.
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Apply changes to the scale of particles.
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Apply a shockwave through particles.
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Simulates fluid dynamics on Particles with an SPH simulation.
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Attracts particles towards a spline.
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Applies a spring simulation on particles.
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Applies turbulence to particles.
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Applies a constant velocity to particles.
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Applies a rotational velocity to particles.
Emitters
Emitter nodes spawn particles that can be manipulated in a particles system.
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Emit particles from a Field system.
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Emit particles from an image.
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Emit particles from a mesh.
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Emit particles from a Point Cache.
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Emit particles from a primitive shape.
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Emit particles from a Procedural system.
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Emit particles from objects within the screen space.
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Emit particles that fill the volume of a mesh.
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Emits particles from a spline.
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Emits particles from other particles.
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Eemits particles from feature points of a video.
Rendering
Rendering nodes visualise the particles by spawning images, meshes or trails.
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Renders particles as a dot-matrix in screen space.
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Renders particles as connected geometry and lines.
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This node generates a 2D Gradient based on the positions and colours of active particles.
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Renders lines between nearby particles.
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Renders lines between pairs of particles.
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[deprecated] Renders Geometry to the position of each particle.
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Renders a each particle as a sprite.
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Renders particles onto nearby Meshes.
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Renders trails which follow the path of particles.
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Renders particles as a density volume.
Shading
Shading nodes change the colour or position of the particles in various ways.
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Shades particles based on their current properties.
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Shades particles by their density.
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Displaces a particle to a primitive shape.
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Shades particles based on their distance from a point.
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Displaces particles based on an image.
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Shades particles based on an image.
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shades particles based on a keyframe animated colour.
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Shades particles over their life span.
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Shades particles based on the area of effect from lights.
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Shades particles using fractal noise.
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Light particles using shadow volumes.
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Light particles using voxel cone shading.
Nodes
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Generates a bounding box from the bounds of a particle system.
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Caches a particle system for potentially faster and repeatable results.
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Modify particles using a dynamic per particle event.
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The root node for a Particle system.