Mist - Mist

This is the place to manage and control the mist's behaviour and physical properties.

Cell size

Since mist is created in voxels, the size of the individual cells determines their amount and finally the resolution. Smaller values will create a better impression of mist with more details, but also take longer to simulate. With high values, the mist clouds can show jagged borders. RealFlow's mist always uses a bounded domain. This value is measured in metres [m].

Solver

You can choose between “Stable” and “Fast”, but we recommend using the second option. It is already very reliable and much faster than the “Stable” method. You should only switch to “Stable” if you encounter problems.

Diffusion

This parameter controls the movement of particles between areas with high and low mist particle concentration. As a result, the mist clouds will expand.

Dissipation

This defines how fast the mist particles will disappear. With higher settings, the mist clouds will vanish faster.

Strength

When RealFlow has identified a particle that will be transformed into mist, the fluid engine transfers a certain amount of mass from the particle to the mist droplet. The transferred amount of mass is used to calculate the density field based on the mist domain’s resolution. So, for instance, if the cell volume of the mist field is 1 m³ and the splash particle volume is 0.05 m³, a density value of 0.05 is added to the mist field at the particle position. If the particle volume is 1 m³ then a value of 1 is added. With “Strength” it is possible to influence this process. “Strength” acts like multiplier for the calculated density value. With values greater than 1.0 you can increase the mist’s density; values smaller than 1.0 lead to a less opaque cloud.

Velocity Scale

Particles, turning into mist, are used to update the velocity field that advects the mist’s density field. This is simply done by adding the particles’ velocity to the mist’s velocity field and the parameter controls exactly this influence. A value of 0.0 means that particles will not contribute to this velocity field at all.

Radius threshold

This parameter is related to the mist-generating splash particles and specifies the radius a splash particle must achieve before it can create mist. The radius of splash particles is normalized and ranges from 1.0 (birth) to 0.0 (death). Therefore, “Radius threshold” only accepts values between 0.0 and 1.0 as well. With 0.3, for example, only splash particles with a radius (or lifetime) larger than or equal to this threshold will be able to create mist.