The → "Filter" daemon in RealFlow | Cinema 4D allows you to define simple comparisons and conditions, so-called expressions, in order to transfer particles between fluid containers.
Let's assume you want to filter the particles from “Fluid_A” against their velocities. If a particle' speed is lower than 2.0 the particle should be transferred to “Fluid_B”:
Target > Fluid_A
Source > Fluid_B
Condition > Expression
Under “Expression” enter:
particle.speed < 2.0
You can use any other keywords from the table and modify the expression to your needs. It is also possible to combine expressions, e.g.
if particle.age > particle.velocity
Attribute | Expression keyword |
---|---|
Age |
|
Collision |
|
Density |
|
Force |
|
ID |
|
Mass |
|
Neighbors |
|
Normal |
|
Position |
|
Pressure |
|
Texture |
|
Velocity |
|
Viscosity |
|
Vorticity |
|
Emitter Id | particle.emitterid* |
* An emitter's Id can be seen in the HUD.