Emit from Geometry

This compound emits new particles from geometry. To use it, you need to plug one or more objects' Value outputs into the Emitter port.

Plug the Emit from Geometry's Emit output into the ICETree node. This compound should be plugged in to the first port of the ICETree node because you usually need to emit particles before any other node or compound can be evaluated.

For more general information, see Creating a Basic Particle Emission.

Tasks: Particles/Emitters

Output Ports: Emit

Enable

Turns the particle emission on and off.

Emission Parameters

Emitter	Plug in the geometry from which you want to emit particles. This must be a geometry with a surface. You can plug multiple geometries into this emitter.
Select Rate Type	The way in which particles are emitted: Total Number of Particles emits all particles set by the Rate parameter at once at the first frame of emission. Number of Particles Per Second emits the number of particles set by the Rate parameter over time. See ICE Particle Rate (Amount) for more information.
Time Varying	Allows the particle emission to evolve over time in a continuous manner.
Emission Type	Emits particles from these components of the emitter object: Points, Surface, or Volume.
Rate	The number of particles that are emitted according to the Select Rate Type you selected. Note that in some cases where particles are deleted immediately using one of the Filter compounds (such as Filter by Weight Map) in the Emission Control group, the actual number of particles that are displayed on screen may be less that this Rate value defines. That is because the Filter compounds delete certain particles immediately after they are born.
Seed	This number is used as the basis for the random generation of particles. If two different particle emitters use the same seed, you may get identical results in their emission. Change the seed value to get a different random generation of particles.

Emission Filter Parameters

Reference	A reference to a weight map or other attribute on the emitter to filter locations by. If this option is used, the attribute is used to control the rate of emission across the geometry. If the emission type is set to "Surface", you can specify a portion of the surface; if the emission type is set to "Point", you can specify the points. The supported types for the attribute are: Boolean, integer and scalar. Integer and scalar values are clamped to a minimum of 0 and a maximum of 1. A value of 0 (or false for Boolean) means the corresponding vertex or triangle is discarded from the set of locations. Scalar values between 0 and 1 are used as weights when the emission type is set to Surface: a triangle will emit N% of the locations that it would have emitted without filtering where N is equal to the weight of the triangle multiplied by 100. The current attribute contexts supported when emitting from a surface are: vertex: the weight of a triangle is the average of the weights of its three vertices. polygon: the weight of a triangle is the value of the attribute at the center of the triangle. polynode: the weight of a triangle is the average of the weights of its three polynodes.
Explore	Click to select the reference from an explorer. You can only choose attributes that are valid at the generated locations.
Pick	Click to launch a picking session and select a reference from a viewport or explorer.
Invert	Inverts the effect of the filter, so that the actual filter will be 1 minus the value of the attribute.
Rate Control	How the rate is interpreted when a filter attribute is specified Exact Rate: the number of samples specified by the Rate value will be generated, but only where the filtering condition is satisfied. Proportional to Filtered Area: the number of particles is reduced proportionally to the area that satisfies the filtering condition.

Initial Values

Mass	Defines how much matter the particles have. The value is in kilograms (kg). The mass is used to determine how the particles are affected by forces and other physical effects. Particles with higher mass values require larger forces to modify their motion. See ICE Particle Mass for more information.
Size	Defines how large the particle is. This value is the particle radius, but the particle display size is the diameter. For example, if the Size value (radius) is 1, the diameter (display) size is 2. Some compounds use the Size value to help with collision detection or to define motion, such as Bounce Off Surface or Stick to Surface, for example. See ICE Particle Size for more information.
Color	Defines the initial particle color as displayed in the viewport. Set the color value using the standard color sliders and color box. Rendered particles do not use the particle color values unless you've set up the shader to do so, such as with an Attribute_Color shader. See ICE Particle Color for more information.
Shape	Defines how the particle shape is drawn on screen. You have a selection of different methods for displaying particles: point, segment (trails), disc, rectangle, sphere, box, cylinder, capsule, cone, and blob. If you select Blob or Capsule, they are displayed as spheres in the viewport. You must render them to see their true shape. To display trails, select Segment. To render sprites, select the Rectangle shape. If you want particles to collide with an obstacle, they require a shape that has 3D geometry, such as a sphere, box, cylinder, capsule, or cone. See ICE Particle Shapes for more information.
Orientation	Defines the orientation of particles when emitted. The particle's orientation stays the same over its lifetime unless some force changes it. Set the axis of rotation in the local XYZ reference frame, and then set the Angle in degrees around that axis. See ICE Particle Orientation for more information.
Align to Surface Normal	Aligns the particle's Y axis to point in the direction of the surface normal of the emitter.
State ID	When using the State nodes to define particle behavior, this value defines which state the particles will be using when created. See Setting the Particle's State ID for more information.

Direction and Speed

Select Emit Direction	Select between two methods of controlling the direction of movement of new particles: Use Emit Direction Normal uses the surface normal of the particle's location at birth to control its initial direction. Use Initial Direction Vector uses the Direction values (below) that you define to control their initial direction. The particle's direction stays the same over its lifetime until some type of force changes it. See ICE Particle Direction for more information.
Direction	If you selected Use Initial Direction Vector as the Select Emit Direction method, you must set this value to control the initial direction of movement for all new particles. These values use global XYZ space. If you set all the axes values to 0, the particles are emitted but stay stuck to the emitter.
Speed	Defines the speed at which new particles are moving when they are emitted, which is the number of Softimage units per second. If this value is set to 0, the particles are emitted, but simply remain on the emitting object. This parameter controls only the initial speed, but you can change it over time using a compound such as Modulate Velocity Over Time. See ICE Particle Speed for more information.
Fast Moving Emitter	If the particle emitter is moving very quickly, you may get "banding" effects as the particles as they're emitted. This is because particles are only emitted at each frame. If the velocity of the emitter is high, then you may see clumps of particles appearing as the emitter moves through space. This option can help smooth out stream of emitted particles so that there is less banding. For greater control over banding effects, especially with emitters that don't move in a linear fasion, you can set the subframe sampling value - see ICE Simulation Subframe Sampling.
Execute on Emit1	You can plug in nodes that have Execute output ports. These ports only get executed once when a particle gets created.

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