Emitter : Emission Spline

Owned by thomas (Unlicensed)
Last updated: 18 Oct, 2018 by Alex Ribao
4 min read

This emitter creates particles and moves them through a force field along a customizable path. Emitters define the point of particle creation in 3D space only, while the particles are part of the domain.

 

 

The parameter set has additional information:

Link Spline

Drag the spline object to this slot and convert it into an emitter. You need one emitter per spline.

Creation Type

Here are your options:

  • "Axis". The particles are created along the spline's path similar to a curtain. Emission direction is indicated in the viewport through small arrows at the spline's control points. This direction can be changed with "Rotation" (see "Control" below).
  • "Tube" The particles are created along the spline's path. The fluid tube's thickness is defined through the circles at each control point. As with "Axis", emission direction is indicated through small arrows.
  • "Edge". The particles are created at the first control point and moved along the spline through customizable forces. The first point's circle represents the area of emission.
Speed

Here the particles' initial speed is defined. Higher values will generate more particles per frame. Faster particles act with stronger forces on other particles or objects. The number of emitted particles also depends on the fluid's “Resolution” settings. A value of 0.0 stops the emission of particles.

Randomness

To avoid regular emission, it is possible to randomly displace the particles at creation time. Higher settings create more randomness. This parameter accepts all values between 0 and 50.

Thickness

This parameter is only available with "Creation" set to "Axis". Here, you control the thickness of the particle stream emitted from the spline's axis – this is also possible on a per-control-point basis (see "Thickness" below under  "Control"). The unit is metres.

Avoid particle intersection

When enabled, Dyverso tries to avoid the creation of particles in areas where particles already exist.

 

Control 

This parameter subsection is used to customize the attributes of every control point. The control point being edited is highlighted in yellow in 3ds Max viewport.

+ Add

This button inserts an additional control point in the spline emitter after the currently selected point. Please, keep in mind that the original spline remains intact.

- Delete

This button removes the currently selected control point.

<= Previous

Navigates to the previous control point in the Spline emitter. The previous control point is the one with a lower offset value.

Next =>

Navigates to the previous control point in the Spline emitter. The previous control point is the one with a bigger offset value.

Offset

You can change the selected control point's position on the spline with this value, e.g.

  • 0.0. The control point is moved to the spline's start.
  • 0.5. The control point is moved to the spline's midpoint.
  • 1.0. The control point is moved to the spline's end.
Radius

The circle around a control point indicates the forces' scope or radius. Only particles inside the viewport's circles will be affected. The circles' sizes can be controlled with this parameter or the viewport gizmo.

Speed

When the emitter is in "Axis" or "Tube" mode it is possible to define different emission speed values for every control point separately:

  • 0 stops the creation of particles at this control point.
  • The adjusted is value will be multiplied with the global "Speed" value under "Emission".
  • The parameter is connected to Maya's scale settings.
Rotation

Every control point has an arrow, indicating the fluid's emission direction in "Axis" and "Tube" mode. By entering a positive degree value this emission direction can be changed. It is also possible to change direction with the viewport gizmo. To see the effect we recommend activating the "Helper" option.

Thickness

It is possible to control the thickness of the emission per control point. The final value will be CP thickness * Thickness.

Vortex

Set the control point's individual vortex strength. Positive values create a clockwise rotation, negative settings create a counter-clockwise rotation around the spline's path.

Axial

Set the control point's individual axial strength. Positive values create an attraction effect towards the spline, negative settings create a repulsion.

Radial

Set the control point's individual axial strength. Positive values create an attraction to the spline's control point, negative settings create a repulsion effect.

Helper

When enabled the direction and strength of emission is displayed in the viewport. If you change the emitter's parameter, e.g. "Speed" or "Rotation", the gizmo will be updated accordingly.

Viewport manipulation

It is possible to manipulate the Offset, Radius and Rotation of the control points directly in the viewport. In order to do it you need to enable the "Select and Manipulate" option in 3ds Max.

 

Select and Manipulate button


When this mode is enabled, several green squares and white lines are superposed over the spline object in the viewport to allow its direct manipulation.

Left to right: manipulation handles for Rotation, Offset and Radius of Spline emitter control points