This attribute is used only if lifespanMode is set to “Random Range”.
The attribute identifies a range of random variation for the lifespan of each particle. If set to a non-zero value, each particle’s lifespan varies randomly up to plus or minus lifespanRandom/2, with the “lifespan” attribute as the mean (the average lifespan). For example, lifespan 5 and lifespanRandom 2 will make the lifespans vary between 4 and 6.
In Constant or Random Range Mode, the finalLifespanPP attribute stores the values generated from lifespan and lifespanRandom.
Changes in the values of lifespan and lifespanRandom affect only new particles, not particles that already exist. For example, if you key the value of lifespan to be 2 up until frame 50 and 5 thereafter, then particles generated from frame 1 to 50 will have finalLifespanPP 2 and particles generated after frame 50 will have finalLifespanPP 5. The finalLifespanPP values of particles born prior to frame 50 will not change.
The Radius Scale ramp sets per-particle radius scale values which are applied to the Radius attribute to compute per-particle radius values. The vertical component represents the Radius Scale values from 0 (no radius) to 1 (equal to the Radius attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
If the Radius Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the radius per-particle attributes are created if they don’t already exist.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Radius Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
When on, the current nParticle object collides with passive objects, nCloth objects, and other nParticle objects that share the same Maya Nucleus solver. When off, the current nParticle object does not collide with passive objects, nCloth objects, or other nParticle objects that share the same Maya Nucleus solver.
Specifies the strength of collisions between nParticles and other Nucleus objects. At the default value of 1, nParticles fully collide with each other and with other Nucleus objects. Collide Strength values between 0 and 1 dampen the full collision, while 0 turns off nParticle collisions (which has the same as effect as turning off the object's Collide attribute). Setting Collide Strength to values greater than 1 slightly increases the force of collisions, while values less than 0 can create a weak repulsive force between objects.
You can set Collide Strength on a per-particle basis with a Collide Strength Scale ramp.
Assigns the current nParticle object to a specific collision layer. Collision Layers determine how nParticle, nCloth, and passive objects that share the same Maya Nucleus solver interact.
nParticle objects on the same collision layer collide normally. However, when nParticle objects are on different layers, particles on lower value layers will have priority over particles on higher value layers. So an nParticle object on collision layer 0.0 will push an nCloth object or another nParticle object on collision layer 1.0, which in turn will push an nCloth object or another nParticle object on collision layer 2.0. This collision priority occurs in the range set by the Collision Layer Range attribute on the nucleus node.
See Collision Layer in the nClothShape node description.
Specifies a self-collision scale value for the current nParticle object. Self Collide Width Scale allows you to scale the thickness of collisions that occur between particles emitted from the same nParticle object. Setting Self Collide Width Scale improves the smoothness of particle emission of self colliding particles, and speeds up the simulation. Self Collide Width Scale is 1.0 by default.
Specifies what Maya Nucleus solver information is displayed in the scene view for the current nParticle object. Solver Display can help you better diagnose and troubleshoot any problems you may be having with your nParticles.
When on, the self-collision volumes for the current nParticle object are displayed in the scene view. Self Collision Thickness helps you visualize nParticle self-collision thickness and it is useful when tweaking nParticle self-collisions (collisions between particles emitted from the same nParticle object).
Specifies the springiness or bounciness of the current nParticle object. Bounce determines the amount of the nParticle’s deflection or rebound on collision with itself, passive objects, nCloth or other nParticles objects that share the same Maya Nucleus solver.
The amount of Bounce an nParticle object should have is determined by the type of nParticle effect. For example, nParticles with a Bounce of 0.0 would not be bouncy (such as steel) and an nParticle with a Bounce of 0.9 would be very bouncy (such as rubber). Bounce is 0.0 by default.
Specifies the amount of friction for the current nParticle object. Friction determines how much nParticles resists relative motion on collision with itself, passive objects, nCloth, and other nParticle objects that share the same Maya Nucleus solver.
The amount of Friction an nParticle object should have is determined by the type of nParticle effect. The affect of Friction is influenced by the nParticle object’s Stickiness value. See Stickiness.
Stickiness specifies the tendency of nParticles to stick to other Nucleus objects when nCloth, nParticle, and passive objects collide.
Stickiness and Friction are similar attributes in that Stickiness is an adhesion force in the normal direction, while Friction is a force acting in the tangent direction. As with Friction, the Stickiness value used in a collision is the sum of the two colliding objects. So, for full sticking, the Friction and Stickiness on the colliding objects should be 1.0. Note that if Stickiness and Friction are both set to 2 on an object, this object will stick to other Nucleus objects that have Stickiness set to 0.
For particles from the same nParticle object to stick to each other, Self Collide must be turned on.
The Collide Strength Scale ramp sets per-particle collide strength scale values. These scale values are applied to the Collide Strength attribute to compute per-particle collide strength. The vertical component represents the Collide Strength Scale values from 0 (no collide strength) to 1 (equal to the Collide Strength attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
If the Collide Strength Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the collide strength per-particle attributes are created if they don’t already exist.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Collide Strength Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
The Bounce Scale ramp sets per-particle bounce scale values. These scale values are applied to the Bounce attribute to compute per-particle bounce. The vertical component represents the Bounce Scale values from 0 (no bounce) to 1 (equal to the Bounce attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
If the Bounce Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the bounce per-particle attributes are created if they don’t already exist.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Bounce Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
The Friction Scale ramp sets per-particle friction scale values. These scale values are applied to the Friction attribute to compute per-particle friction. The vertical component represents the Friction Scale values from 0 (no friction) to 1 (equal to the Friction attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
If the Friction Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the friction per-particle attributes are created if they don’t already exist.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Friction Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
The Stickiness Scale ramp sets per-particle stickiness scale values. These scale values are applied to the Stickiness attribute to compute per-particle stickiness. The vertical component represents the Stickiness Scale values from 0 (no stickiness) to 1 (equal to the Stickiness attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
If the Stickiness Scale Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the stickiness per-particle attributes are created if they don’t already exist.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Stickiness Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
If you prefer that a field affect a particle object in its local space, select the particles, display the Attribute Editor, and turn off Forces In World.
Note that the orientation of the local axes of a particle object matches the orientation of the world space axes unless you rotate the object.
Applies a force similar to Nucleus Gravity to the nParticle object in the amount and direction specified. The force is applied locally and does not affect other Nucleus objects assigned to the same solver.
The total force acting on the nParticle, is the sum of the set Nucleus Gravity and Local Force. For example, to double the force of gravity acting on the object, set the Local Force Y value to -9.8. Turn on Ignore Solver Gravity if you want only the Local Force to affect your nParticle object.
Applies a force similar to Nucleus wind to the nParticle object in the amount and direction specified. The wind is applied locally and does not affect other Nucleus objects assigned to the same solver.
The total wind acting on the nParticles is the sum of the set Nucleus wind and Local Wind. Turn on Ignore Solver Wind if you want only the Local Wind to affect your nParticle object.
The Conserve value controls how much of a particle object’s velocity is retained from frame to frame. Specifically, Conserve scales a particle’s velocity attribute at the beginning of each frame’s execution. After scaling the velocity, Maya applies any applicable dynamics to the particles to create the final positioning at the end of the frame.
Conserve doesn’t affect motion created by keyframes. Keyframes affect only a particle object’s worldVelocity attribute, not its local velocity attribute.
If you set Conserve to 0, none of the velocity attribute value is retained. The velocity is reset to 0 before each frame. At the end of each frame, the velocity is entirely the result of dynamics applied during that frame.
If you set Conserve to 1, the entire velocity attribute value is retained. This is the real-world physical response.
If you set Conserve to a value between 0 and 1, a percentage of the velocity attribute value is retained. For example, if you set Conserve to 0.75, each frame Maya first reduces the velocity attribute 25%, then it calculates any dynamic or expression effects on the object.
For example, suppose you create a particle falling with the acceleration of gravity, 9.8 units per second per second. The following table compares how Conserve values of 1 (default), 0.5, and 0 affect the velocity attribute after several frames execute.
With Conserve set to 1, velocity increases each frame at the exact acceleration rate of gravity.
With Conserve set to 0, velocity stays a constant value—the particles do not accelerate. At the beginning of each frame, velocity is reset to 0. The gravity field’s acceleration is then added to the velocity of 0, which results in the same number <<0,-0.41,0>> being used at the end of each frame.
With Conserve set to 0.5, velocity increases each frame at a much slower rate than gravity. At the beginning of each frame, velocity is scaled to 50% of the value it had at the end of the prior frame. The acceleration of gravity is then added to this scaled value to create the slowly increasing velocity used at the end of the frame.
Specifies the base mass of the current nParticle object. Mass determines the density or the weight of an nParticle object when its Maya Nucleus solver’s Gravity is greater than 0.0.
The Mass an nParticle should have is determined by the type of nParticle effect you want to achieve.
Mass affects behavior in collisions and behavior with Drag. nParticles with high Mass have greater influence on other nParticle or nCloth objects with low Mass, and they are less influenced by Drag.
The Mass Scale ramp sets per-particle mass scale values which are applied to the Mass attribute to compute per-particle mass values. The vertical component represents the Mass Scale values from 0 (no mass) to 1 (equal to the Mass attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Mass Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
Generates a force field that can push (positive fields) nCloth objects and other nParticle objects away from the current nParticles, and pull (negative fields) nCloth objects and other nParticle objects toward the current nParticles. A Point Force Field can only be exerted on Nucleus objects that are assigned to the same Nucleus solver as the nParticle object generating the Point Force Field.
Sets the orientation of the Point Force Field.
Point Force Field is relative to the radius of individual nParticles. nParticles with higher Radius values generate stronger Point Force Fields relative to nParticles with low Radius values.
See Radius.
Sets the strength of self attractive forces between the points (individual particles) of an nParticle object. Positive Self Attract values pull the points (individual particles) of an nParticle object together. Negative Self Attract values push the points (individual particles) away from each other.
Sets a Point Field Scale ramp that can be used to vary Point Field Magnitude along the Point Field Distance. See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map Point Field Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
Sets a ramp that specifies how much the Point Field Magnitude drops off as you move away from the nParticle and toward the edge of the area defined by Point Field Distance. See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
When on, nParticles rotate on a per-particle basis after they collide or self-collide. Compute Rotation also creates Rotation PP and Angular Velocity PP per-particle attributes on the nParticleShape node.
You can use Rotation PP to rotate instanced geometry on a per-particle basis. Rotation PP and Angular Velocity PP can be used with an expression to add and control per-particle rotations.
Sets the amount of friction that is applied to particles during collision or self-collision. Increasing Rotation Friction increases the tendency of particles to rotate. When set to 0, particles do not rotate.
You can add Rotation Friction PP as a dynamic attribute and use it to control rotations in an expression.
Specifies the amount of damping applied to the nParticle's rotational velocity. Increasing Rotation Damp causes particle rotation to slow down after collision or self collision. When set to 0, no damping is applied to the rotation, causing the particles to rotate forever if no collisions or self collisions occur.
You can add Rotation Damp PP as a dynamic attribute and use is to control rotations in an expression.
Specifies the distance over which the wind created by the motion of the current nParticle object affects nCloth objects or other nParticle objects in the same Nucleus system. The motion of the current nParticle object determines the direction of the wind.
When Air Push Distance is 0, no wind is generated by the motion of the current nParticles. When Air Push Distance is greater than 0, the wind created by the motion of the current nParticle object affects nCloth or other nParticle objects in the same Nucleus system. The higher the Air Push Distance, the greater the distance over which the wind created by the motion of the current nParticle object affects nCloth or other nParticle objects in the same Nucleus system.
Specifies the amount of circulation or rotation in the flow of air being pushed by the current nParticle object, as well as the amount of curl in the flow of wind created by the motion of the current nParticle object. Air Push Vorticity changes the direction of the wind created by the motion of the current nParticle object.
Air Push Vorticity only affect’s your nParticles when Air Push Distance is greater than 0.
Specifies the distance over which the current nParticle object blocks the dynamic wind of its Nucleus system from other nParticle, nCloth, and passive objects in its system.
When Wind Shadow Distancee is 0, no wind is blocked by the current nParticle object. When Wind Shadow Distance is greater than 0, the dynamic wind of its Nucleus system is blocked by the current nParticle object. The higher the Wind Shadow Distance, the greater the distance for which the current nParticle object blocks the dynamic wind of its Nucleus system.
When on, Liquid Simulation properties are added to the nParticle object. See Liquid Simulations.
Viscosity represents the resistance of the liquid to flow, or how thick, and non-liquid the material is. When this value is high, the liquid flows like tar. When this value is small, the liquid flows more like water. For example, a value of 0.01 produces water-like liquids. For more viscous liquids, use a value of 0.1.
Increasing Substeps on the nucleus node magnifies the affect of Viscosity.
The Viscosity Scale ramp sets per-particle viscosity scale values. These scale values are applied to the Viscosity attribute to compute per-particle viscosity. The vertical component represents the Viscosity Scale values from 0 (no viscosity) to 1 (equal to the Viscosity attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Viscosity Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
Specifies the amount of surface tension applied to liquid nParticles. Surface Tension is an attractive force that creates contracting and expanding behavior on the surface of a liquid nParticle object as it moves. The effects of Surface Tension are intended to add realistic surface tension to your nParticle liquid simulations.
The higher the Surface Tension values, the greater tendency nParticles have to attract one another, which causes the overall surface area of the nParticle object to become smaller and more uniformly covered.
Surface Tension affects the behavior of all nParticles belonging to the object, not just those that are visible at the surface of the liquid effect.
The Surface Tension Scale ramp sets per-particle scale values. These scale values are applied to the Surface Tension attribute to compute per-particle surface tension. The vertical component represents the Surface Tension values from 0 (no surface tension) to 1 (equal to the Surface Tension attribute value). See nParticle internal ramps and per-particle attributes and Set nParticle internal ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the Surface Tension Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
Output Mesh attributes allow you to control the size, smoothness, and dynamic characteristics of Blobby Surface nParticle objects when they are converted to polygon meshes. To see the effects of Output Mesh settings, you must first convert your nParticle object to a polygon mesh by selecting Modify > Convert > nParticles to Polygons. nParticles must be either created or emitted into the scene to be converted to polygons. nParticles emitted after the conversion will continue to add to the size and overall appearance of the nParticle output mesh. Output Mesh attributes are applicable all Particle Render Type nParticles. However, the nParticle output mesh always creates an iso-surface, which is based on nParticle Radius and Threshold.
After your nParticle object is converted to a polygon object, Maya no longer displays the particles in the scene view. This reduces simulation time and makes it easier to see how your Output Mesh attribute adjustments affect the mesh. To make the nParticle object visible in the scene, in the Object Display section of the nParticleShape node Attribute Editor, turn off Intermediate Object.
Specifies the amount nParticle Radius is scaled to create an appropriately smooth surface on Blobby Surface nParticles. Increasing Blobby Scale Radius does not affect nParticle Radius, meaning that nParticles can overlap due to Blobby Scale Radius without affecting their dynamic behavior. Increasing Blobby Scale Radius and Threshold together create smooth surfaces on nParticle output meshes.
Motion Streak elongates individual nParticles based on the direction of nParticle motion, as well as the distance the nParticle travels in one time step. When Motion Streak is 0, nParticles are round. When Motion Streak is 1, nParticles are elongated to a length that is equal to the distance travelled in one time step. Motion Streak applies only to nParticles converted to nParticle output meshes. Motion Streak is useful for creating a motion blur type of effect, and for shaping the flow of Liquid Simulation effects.
Determines the size of the triangles used to create the nParticle output mesh. Small Mesh Triangle Size produces high resolution output meshes with smoother surfaces. Small triangles take more computing resources and time to simulate. Mesh Triangle Size can be affected if the particle system bounds are very large relative to the set Mesh Triangle Size. See Max Triangle Resolution.
Specifies the grid size that is used to create the output mesh. Max Triangle Resolution clamps the resolution of the voxel grid used in generating the nParticle output mesh's triangles. If the grid size required to create an nParticle mesh exceed the Max Triangle Resolution value, the output Mesh Triangle Size automatically increases to compensate for increasing size of the mesh.
Specifies the type of polygon mesh used to generate the nParticle output mesh iso-surface. By default, Mesh Method is set to Triangle Mesh.
Specifies the amount of smoothing applied to the nParticle output mesh. Smooth iterations increase the lengths of the triangle edges, making the topology more uniform, generating a smoother iso-surface. The smoothness of your output mesh increases with increased Mesh Smoothing Iterations values, however, calculation time also increases.
When on, incandescence per-vertex data is generated when you convert an nParticle object to an output mesh. Incandescence per-vertex data is derived from the nParticle object's per-particle incandescence values. The data is color set data and can be applied to the nParticle output mesh like other color set data.
When on, velocity per-vertex data is generated when you convert an nParticle object to an output mesh. Velocity per vertex is derived from the internal mapping of nParticle velocity values to R, G, and B color values. You can use velocity per-vertex data to create motion blur when the mesh is rendered using mental ray for Maya renderer.
Velocity per-vertex data is passed to the output mesh through the polySurfaceShape node's color set named Motion Vector Color Set. By default this color set uses the velocityPV data generated from the nParticle object.
When on, UVW texture coordinates are generated when you convert an nParticle object to a polygon mesh. The texture coordinates let you map a texture to the surface of your output mesh. See nParticle output meshes.
You may need modify the meshes' UVs to get the desired placement of the texture on the mesh. You can view and edit UVs using the UV Texture Editor. For more information about UVs, see Introduction to UV mapping and UV mapping overview in the Modeling guide.
When on, user normals are created for the output mesh. The normals are based on the direction of the opacity gradient within the particle density. This can improve the appearance and smoothness of the nParticle output mesh, particularly in areas of the mesh that have thin triangles. This setting only affects the output nParticle mesh and not volume nParticle renders.
Specifies the simulation data that will be saved to a server or local hard drive when the current nParticle object is nCached.
This boolean attribute tells the particle object to assume that particles created from emission are in world space, and to transform them into object space before adding them to the particle array. This makes the particles respond as if they were in the same space as the emitter when they are in some non-identity hierarchy.
The Opacity Scale ramp sets per-particle opacity scale values which are applied to the Opacity attribute to compute per-particle opacity values. The vertical component represents the Opacity Scale values from 0 (no opacity) to 1 (equal to the Opacity attribute value). Work with nParticle attribute ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map Opacity Scale ramp values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
The Color ramp defines a range of color values used for nParticle. The particular colors selected from this range correspond with the values for the selected Color Input. Color Input values of 0 map to the color at the left of the ramp, Color Input values of 1 map to the color at the right of the ramp, and values between 0 and 1 map to the color corresponding with the position on the ramp. Work with nParticle attribute ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the ramp's color values.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
Incandescence controls the amount and color of light emitted from the nParticles due to self illumination. The particular colors selected from this range correspond with the values for the selected Incandescence Input. Incandescent emission is not affected by illumination or shadowing. If the Incandescence Input is set to Off, the per-particle attributes are deleted. If it is set to any other value, the incandescence per-particle attributes are created if they don't already exist. Work with nParticle attribute ramps.
Controls the way per-particle attribute values blend between each position on the ramp. The default setting is Linear.
Specifies which attribute is used to map the ramp's color values.
When off, the per-particle attributes are deleted. If you want to use an expression with the per-particle attribute, you need to manually add them again. See Set attributes on a per particle basisin the Dynamics guide.
The per-particle attribute values are determined by the nParticle’s age, which is based on the particle Lifespan mode. See Lifespan Attributes in the Dynamics guide.
The per-particle attribute values are determined by the normalized age of the nParticle. To use Normalized Age, the nParticle object must have a defined lifespan. For example, the nParticle object’s Lifespan Mode attribute must be set to Constant or Random range. See Lifespan Mode in the Dynamics guide.
When Normalized Age is used, The per-particle attribute values are mapped within the range of the nParticle object’s lifespan.
See Set attributes on a per particle basis and Per particle and per object attributes.
Details on particle expressions can be found in the MEL and Expressions book.
