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Spray Particle System 245
Inter face
Par ticles group
Viewport Count—Maximum number of particles
displayed in view p 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 par ticles 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 S ize—Size of a particle in the active units.
Speed—Initial velocity of each particle as it leaves
the emitter. Particles travel at this speed unless
they are affected by a particle system space warp.
Variation—Varies the initial speed and direct ion of
particles. The greater the Variation, the st ronger
and broader the spray.
Drops, Dots, or Ti ck s—Choose how particles are
displayed i n viewports. The display s etting 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 with 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 de ath"
rates of emitted particles.
At the bottom of the Timing group is a line that
displays the maximum sustainable r ate. This value