nxSheeter

nxSheeter fills thin, stretching fluid films with new particles, so a sheet of liquid holds together instead of tearing early into isolated droplets.

As a fluid stretches into a thin sheet, gaps open between its particles and the film breaks up. nxSheeter watches for those thinning regions and inserts fresh particles into the gaps, bridging them so the sheet stays continuous. It runs on top of an existing NeXus fluid and only ever adds its own particles: it never moves or removes the source fluid.

Add it from Add ▸ INSYDIUM NeXus ▸ nxSheeter. It arrives as an empty and all of its settings live in Properties ▸ Physics. Point it at a fluid by adding the fluid’s nxGroup to Groups Affected, or leave that empty to act on every particle.

A fast jet of liquid slams into Suzanne and bursts into a sheet of spray. nxSheeter continuously refills the stretching film as it fans out, so the splash reads as connected sheets of water rather than breaking straight up into loose droplets.

Object Properties

The nxSheeter Object Properties panel

The nxSheeter panel in Properties ▸ Physics, on the Object Properties tab. Its controls are grouped into four sections: Sheet Detection, Particle Creation, Output and Limits.

nxSheeter off

nxSheeter on

The same jet fanning off the disc, shown as its individual fluid particles. With nxSheeter off, on the left, the thin sheet is undersampled and tears into a sparse scatter of separated droplets. With it on, on the right, fresh particles are inserted into the gaps, so the film fills in and spreads as one continuous sheet.

Enabled

Turns nxSheeter on or off. Disable it to stop the fill without deleting the modifier or losing its settings.

Sheet Detection

Decides which parts of the fluid count as a thin sheet worth filling.

Min Density

The lowest density that still counts as a sheet to fill. Film below this is too sparse and is left to tear into droplets. Raise it to break thin film into spray sooner. Defaults to 0.05.

Max Density

Fluid denser than this is left alone, so only the surface film is filled and not the bulk of the body. Defaults to 0.7.

Search Radius

The size of the neighborhood used to detect sheets, measured in particle radii. It needs to be large enough to span a few neighboring particles. Defaults to 10.

Spawn After Age

How long a particle must exist before the sheeter fills around it. 0 (zero) fills immediately. Raise it so sheets only form once the fluid has been moving. Defaults to 0.

This is a time value, with a clickable f/s toggle to set it in frames or seconds. The same toggle appears on every time control on this page.

Check Age

Stops sheeting a particle once it is older than the Max Age below, so only freshly moving fluid forms sheets. Off by default. When on, it enables the two controls below.

Max Age

Particles older than this are no longer sheeted. Defaults to 2. Enabled by Check Age.

Variation

A per-particle random spread around the Max Age, so the cutoff is not a hard line. Defaults to 0. Enabled by Check Age.

Particle Creation

Controls how the gaps are found and how densely they are filled.

Min Hole Size

The smallest gap worth filling, in radii. Below this the film is already dense enough. Defaults to 1.

Max Hole Size

The largest gap to bridge, in radii. Bigger gaps are left as real tears rather than filled. This is capped by Search Radius. Defaults to 8.

Separating Only

Only fills pairs of particles that are moving apart, so sheeting happens where the film is actively stretching. On by default.

Max Speed

Skips particles moving faster than this, so fast ballistic spray is left to fly instead of being sheeted. 0 (zero) turns the speed gate off, which is the default. This is a velocity value.

Relative Speed

Only fills pairs whose closing or separating speed falls inside the range below. Off by default. When on, it enables the two speed controls below.

Min Speed

The lowest pair relative speed that still sheets. Defaults to 0. Enabled by Relative Speed.

Max Speed

The highest pair relative speed that still sheets. Defaults to 5. Enabled by Relative Speed.

Velocity Alignment

Only fills toward partners that lie along the particle’s direction of motion, within the Alignment Angle below. On by default.

Alignment Angle

The half-angle of the velocity-alignment cone. Wider fills more of the sheet, narrower restricts the fill to the direction of motion. Defaults to 60°, up to a maximum of 90°. Enabled by Velocity Alignment.

Insert Spacing

The spacing held between inserted particles, in radii. This is the main density lever: smaller packs more particles in, larger fills sparser. Defaults to 2.

Min Spacing

The closest an insert may sit to another particle, in radii. 1 keeps the sheet from overlapping. Lower it to over-pack, which adds pressure that helps a splash push out. It is bounded only by Max Particles. Defaults to 1.

Jitter

A random offset added to each inserted particle, in radii, to break up the even lattice for a more natural look. 0 (zero) is a perfectly even fill, which is the default.

Output

Controls where the new particles go and how they look.

Output Emitter

The emitter to create the new particles in. Only an nxEmitter can be picked. Leave it empty to add the particles to the source fluid.

Group

The nxGroup to add the new particles to. Leave it empty to inherit the source particle’s group.

Particle Radius

The radius of the new particles. 0 (zero) inherits the source particle’s radius, which is the default.

Velocity Scale

Scales the velocity the new particles inherit from the fluid. Leave it at 1 to match the fluid. Defaults to 1.

Custom Display

Gives the new particles a fixed color and display mode instead of inheriting the source particle’s. Off by default. When on, it enables the Color and Display controls below.

Color

The color of the new particles when Custom Display is on. Defaults to a light blue.

Display

How the new particles are drawn in the viewport. It offers the same set of shapes as an emitter’s display mode, and defaults to Points. Enabled by Custom Display.

Adaptive Collapse

Removes this modifier’s added particles once their region thickens back into bulk fluid. It never affects the source fluid. Off by default.

Remove Sparse

Culls this modifier’s inserted particles once they are left isolated, so stray sheet particles do not linger after the film tears away. It never touches the source fluid. Off by default. When on, it enables the two controls below.

Min Distance

An insert with no neighbor within this distance counts as isolated and is removed. Defaults to 0.1. Enabled by Remove Sparse.

Max Density

An insert whose local density falls below this counts as sparse and is removed. Defaults to 0.1. Enabled by Remove Sparse.

Limits

Max Particles

Stops adding particles once the total reaches this count. 0 (zero) means unlimited, which is the default. Use it as a hard budget on how many particles the fill can create.

Groups Affected

Use the Groups Affected tab to restrict nxSheeter to particles in specific nxGroup groups, so it fills only the fluid you point it at rather than every particle in the scene. Leave it empty to affect all particles.

Mapping

Use the Mapping tab to drive nxSheeter’s settings from particle data instead of fixed values. See Mapping for how this works.

Falloff

Use the Falloff tab to limit where nxSheeter acts. Add one or more nxFalloff objects to the list and blend them, so only particles inside the falloff region are filled.