8

Spray Particle System 241
Inter face
Par ticles group
Viewport Count—Maximum number of particles
displayed in viewp orts at any given frame.
Tip: Setting the viewport count less than the render
coun t can improve viewport performance.
Render Count—Maximum number of particles that
canappearinasingleframewhenyourenderit.
Works in combination with the particle system’s
timing parameters.
• When the number of particles reaches the
Render Count value, particle creation is
suspended until some particles die.
• When enough particles die, particle creation
resumes until Render Count is reached again.
Drop Size—Size of a particle in the active units.
Speed—Initial velocity of each particle as it leaves
the emitter. Part icles t ravel at this speed unless
they are affected by a part icle system space warp.
Variation—Varies the initial speed and direct ion of
particles. The greater the Variation, the stronger
and broader the spray.
Drops, Dots, or Ti ck s—Choose how par ticles are
displayed in viewpor ts. The display setting does
not affect how particles are rendered. Drops are
streaks that appear like raindrops, dots are points,
ticksaresmallplussigns.
Render group
Tetrahedron—Particles are rendered as long
tetrahe drons, with the length you specify in the
Drop Size parameter. Tetrahedron is the default
setting for rendering. It provides a basic simulation
of water drops.
Facing—Particles are rendered as square faces
whose width and height equals the Drop Size.
Facing particles always face the camera (or
the user’s perspective). They are provided
especially for use w ith material maps. Use
with an appropriate opacity map for bubbles or
snowflakes.
Note: Facing works correctly only in a perspective
or camera view.
Timing group
Timing parameters control the "birth and death"
rates of emitted particles.
At the bottom of t he Timing group is a line that
displays the maximum sustainable rate. This value