"DSpline" is a complex daemon with versatile settings and fields of application. Its parameters and control options are very similar to RealFlow’s "Spline" emitter. "DSpline’s" unique ability to combine forces from different directions gives you the freedom to create all kinds of swirling effects, for example. Control points (CP) provide the ability to define the strength of the forces for each zone individually and you can even add new control points. Of course, the control points can be animated, but it is better to control them with parented "Null" objects, instead of animating them directly.
To edit the control points it is necessary to switch to RealFlow’s “Move” mode by pressing the W key or select the appropriate icon. It is only possible to edit the points with this mode, rotation and scale have no effect. The standard spline emitter shows three control points, surrounded by yellow circles. These circles represent the zones of influence of the various forces. Each of these zones can be adjusted individually and it is also possible to add or remove control points, but you cannot delete the three default control points.
The daemon’s height (up-down direction) can be adjusted with Node > Scale, while scale changes in horizontal direction have no effect. Height changes always depend on your preferences – some programs use the Y axis, others Z.
Changing and adjusting a spline emitter’s shape needs a little practice and experience, but if you are familiar with splines from illustration or 3D programs it should not take very long to achieve full control. Please note that moving one control point affects the shape of the entire spline. To give you a better understanding of the "DSpline" daemon, it is necessary to know its parts and elements.
A. The small yellow dots are the spline’s control points.
B. Each yellow circle shows a control point’s radius. This radius can be seen as a zone of influence of the control point’s settings and parameters. Particles can also be deleted when leaving the yellow circle.
C. The straight line from up to down represents the spline’s curvature or path. It will be adjusted dynamically while moving the control points.
D. The dots at the beginning and the end of the spline are tangent control points.
Affect
Particles can be affected in two ways: either by “Force” or “Velocity”. The first option applies an external force, resulting in an acceleration, while the second one only modifies the velocities of the particles without introducing an additional acceleration. “Velocity” is not available for rigid bodies.
Vortex strength
The “@ CP vortex” settings for all control points are multiplied with this value.
Axial strength
The “@ CP axial” settings for all control points are multiplied with this value.
Radial strength
The “@ CP” radial settings for all control points are multiplied with this value.
EDIT CP
When you click on this button, RealFlow enables the edit mode for the daemon’s control points. Once hit, it turns yellow and the following settings become accessible.
Insert CP
This button requires a control point selection. Activate one of the existing points, click on the button, and the new control point is created above the currently chosen one.
Delete CP
With this button it is possible to remove the currently selected control point.
@ CP index
Each control point has its own index number. You can quickly browse to the desired point by simply entering its index.
@ CP axial
This value represents the control point’s force along its vertical axis.
@ CP radial
This is the strength of the force that attracts or repels particles to the spline.
@ CP vortex
Here it is possible to set the strength of a vortex force around the spline’s path. It forces the particles (or objects) to orbit the spline.
@ CP radius
The yellow circles around each control point indicate the zone of influence. The radius, given in metres [m], of these circles can be increased or reduced with this parameter. The new radius will be automatically updated and displayed in the viewport.
@ CP link
As mentioned earlier, it is not advised to animate the control points directly. You can achieve much better control over the movement by linking a point to the motion of a helper object, e.g. a "Null". You can link each point individually to another "Null". This function opens a node picker where you can choose the desired object to be linked.