Emitter : Emission Spline

Owned by thomas (Unlicensed)
Last updated: 21 Feb, 2019 by Hector Artal (Unlicensed)
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. Here is how to create and edit such an emitter:

  • Create a spline with Cinema 4D's built-in tools.

  • Drag the spline to the “Spline Object” entry.

  • To change the path's shape, change to “Point” mode and shift the points.

Very nice effects can be achieved with animated splines, e.g. a "Cycloid" with an animated "End Angle".

 

 

The parameter set has two subcategory:

RealFlow Scene

In RealFlow | Cinema 4D it is possible to use multiple "Scene" trees in the same project:

  • To link the emitter to a different scene tree dragging the appropriate "Scene" node to this field 
  • Furthermore you have direct access to the selected "Scene" tree's → "Solver", → "Cache", and → "Display" tabs. For descriptions of these parameters follow the links.

To link the emitter to a "Fluid" drag the appropriate "Fluid" node(s) to this field.

To learn more about how to link RealFlow scene elements and make them interact take a look at the → "Manual Linking" page with examples.

Emitter Type

Toggle the emitter type with this drop-down menu. The following parameters and the viewport representation will be updated according to your selection. Bear in mind that type changes will change the emitter's and fluid's behaviour completely.

Spline Object

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

Creation

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 circles. 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 circle. 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

Add Control Circle

Add a new control circle.

Default

Reset all the existing control circles nodes attached to the spline emitter to default values. 

Reset

Remove al existing control circles and create a new ones with default values.

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.

Spline Control Circles Nodes

Spline control circles nodes are used to control the particle emission from the spline.

 

Segment

Determines in which segment of the spline you want to place this control circle (only use for spline with more than one segment).

Offset

Control circle'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

Determines the fluid stream's thickness when Emission > Creation is set to "Tube" or "Edge". You can use the viewport gizmo as well.

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 circle.
  • The adjusted is value will be multiplied with the global "Speed" value under "Emission".
  • The parameter is connected to Cinema 4D'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.