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

These parameters let you use weight maps to help filter the particle emission. The Generate Sample Set node is used under the hood for these parameters.

Rate Control

You can select one of these methods for setting the particle rate when filtering with a weight map:

Exact Rate: Emits the exact number of particles as set by the Rate parameter.
Proportional to Filtered Area: Uses the values from the weight map specified below to filter the emission.

Invert

Uses the inverse weight map values so that particles are emitted only where the weight map values are 0.

Reference

The weight map and its Weights attribute reference. The string in the text box should look something like this (but using your own "weight_map" name instead):

.cls.WeightMapCls.Weight_Map.Weights

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 Orientation of the particle around its local X, Y, and/or Z axes. Then set the Angle value, which is the amount of rotation in degrees around these axes. 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.