Basic Emitter Attributes
Emitter type Select one of these choices from the pop-up menu:
Rate
Scale Rate by Object Size
Use Per-Point Rates (Rate PP)
Omni Sets the emitter type to an omnidirectional point emitter.
Particles emit in all directions.
Directional Sets the emitter type to a directional point emitter.
Particles emit in the direction you specify with the Direction X, Y, and Z attributes.
Surface Emits particles from randomly distributed positions on or near a NURBS or polygonal surface.
Curve Emits particles from randomly distributed positions on or near a curve.
Volume Emits particles from a closed volume. You pick the shape from the Volume Shape pulldown.
Sets the average rate at which particles are emitted per second. The rate is absolute, unless you turn on Scale Rate by Object Size, see below.
Note that emission occurs only if your animation plays two or more consecutive frames with the emitter rate set to a positive value.
If you want to see how many particles have been emitted, select the emitted particle object and examine the Count in the General Control section of the Attribute Editor.
If you turn on this attribute, the size of the object emitting the particles affects the rate of particles emitted per frame. The larger the object, the greater the rate of emission. The attribute is off by default.
For surface emission, the rate is particles per centimeter of area per second. For example, a 2 cm by 2 cm plane has an area of 4 square cm. If the emission rate is 3, the plane emits roughly 12 particles each second. If you use inches or other units, Maya converts the units to centimeters to make the rate calculation.
For curve emission, the rate is particles per cm length per time unit. For le, a 4 cm curve with a rate of 3 emits roughly 12 particles per second.
If this attribute is turned off (the default), the emission rate is absolute, which is how Power Animator behaves, instead of relative to object size, which is how previous versions of Maya behave.
See "Varying emission from different points of point emitters" on page 97.
Need Parent UV
Cycle Emission
Cycle Interval
Min Distance
Max Distance Direction X, Y, Z
(NURBS Surface emitters only) If you turn this on in the Emitter Options window (before you create the emitter), Maya adds parentU and parentV attributes to the particle shape and sets the needparentUV attribute to on. You can use parent UVs to drive the value of some other parameter such as color or opacity.
If you turn this on in the Attribute Editor or Channel Box (after you create the emitter). Maya sets the needParentUV attribute to on, it does not add the attributes.
Cycle Emission lets you restart the random number sequence of the emission. You can use it to create simple cycles for games work.
If you set it to Frame, the sequence is restarted after the number of frames you specify in Cycle Interval (same as Time Random on in Power Animator).
If you set it to None, the random number generator is not restarted (same as Time Random off in Power Animator.
Defines the interval in frames for restarting the random number sequence when using Cycle Emission.
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