VecFlow0.1.0
FlowsOperators

Chance Test

Send particles on to another event at random, so often a second on average: blinking, flickering, random breaks.

VecFlow 0.1.0

Particles go along the wire at random, this often each second on average.

Add it
EventAdd OperatorTestsChance Test
Sends on
Along its wire: particles picked at random.
Influence
Yes: it works only on particles whose value is above a half.

When to use it

When particles should change at random times, not all together: fireflies that blink, embers that flare, snowflakes caught by a gust now and then, debris that crumbles one piece at a time.

Set it up

A flow of 2 events. Dark: Birth, Position, Turbulence, Colour, Chance Test; Chance Test: 0.3 per second sends to Lit. Lit: Colour, Turbulence, Age Test; Age Test: at 0.4 s since entering sends to Dark.DarkChance Test: 0.3 per secondBirth: 80 all at once. Make new particles: some every frame, all at once, one on each vertex of an object's mesh (for cloth and ropes: bind them with Bind, Mesh Edges), one on each piece of it (to smash: glue them with Bind, Pieces), or the event's Liquid filling itBirth: 80 all at oncePosition: Meadow, volume. Place new particles in an object's box, on its surface or inside it, or along a curve (a tube round it)Position: Meadow, volumeTurbulence: 0.5. Push particles around in swirlsTurbulence: 0.5Colour: dark green. Set the colour of particles entering the eventColour: dark greenChance Test: 0.3 per second. Particles go along the wire at random, this often each second on averageChance Test: 0.3 per secondInLitAge Test: at 0.4 s since enteringColour: bright yellow. Set the colour of particles entering the eventColour: bright yellowTurbulence: 0.5. Push particles around in swirlsTurbulence: 0.5Age Test: at 0.4 s since entering. Particles reaching an age go along the wireAge Test: at 0.4 s since enteringIn
Fireflies: now and then each lights up for 0.4 s, then goes dark again.BirthForcesPhysicsLooksTests

Settings

As the flow editor’s sidebar shows them. Changing any of them marks the bake old; those marked Keyframable can also change through a bake.

Per Second
Keyframable
0.50 to 10

How often each particle goes, per second, on average.

InfluenceEmpty

One of the flow’s number values, to weigh it by, particle by particle. Empty for all of it, on all of them. See Influence.

Per Second

How often each particle goes, a second, on average. At 0.5 a particle goes after two seconds on average: about 4 in 10 within the first second, and a few not for many seconds. At 0 none go.

The draw is new every substep and weighed by its length, so the bake's substeps don't change how often they go.

The wire

Not wired, a Chance Test does nothing: particles stay. The first test in the stack that picks a particle out wins.

Works with

  • Keyframe Per Second to make it likelier as the shot goes on.
  • Set Value From Chance marks a share of the particles once, for good; a Chance Test sends some on every second.
  • Influence: weighed by a value, only particles whose value is above a half are tested.

Problems you may see

The editor raises no problems of its own for Chance Test.

Struck Test

Send rigid bodies on when another body strikes them hard enough: knock bricks from a wall held still, or set off a chain.

Group Test

Send particles born on a mesh's vertices on to another event by a vertex group: hang cloth by its corners, pin a rope's end.

On this page

When to use itSet it upSettingsPer SecondThe wireWorks withProblems you may seeRelated