Daemons - Magic

Owned by thomas (Unlicensed)
04 Feb, 2014
5 min read

“Magic” is one of the most powerful daemons in RealFlow and works like a “morphing engine”. This means that the daemon turns the attached object into an attractor, pulling the particles towards its faces. During this process you can apply other daemons to introduce supporting or disturbing forces. They will, of course, fully interact with the "Magic" daemon and help you to create a more vivid and interesting simulation. This daemon is only available for use with particles.

Another idea would be to animate magic’s strength for achieving repulsion and attraction effects. Especially in combination with Python scripts, this daemon can create astonishing results. A useful trick is to use a "Drag Force" daemon combined with the "Magic" daemon to obtain faster convergence of the particles around the object and avoid orbiting effects. This daemon introduces a global force and cannot be scaled or bounded. Please note that the "Magic" daemon offers an additional feature: for “Approach strength” and “Escape strength” it is possible to use (even animated) bitmaps instead of fixed values.

 

 

 

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.

Object

As with other daemons, this option opens a node picker. You can select any available object from the list and the particles will finally adopt the shape of the chosen item. Please note that multi-selections are not supported. The Magic daemon works with particles only, hence it is not possible to attract rigid bodies forming a certain shape with this type.

Approach strength

To control the force at which the particles are attracted to the target object, this value is needed. Higher settings create a clearly visible overshoot, where the particles can partially leave the object of interest and become attracted again. This results in a more or less dynamic wobbling, depending on “Approach strength”. Instead of a fixed value, that is valid for the entire object, it is also possible to apply a map, defining stronger and weaker zones of attraction. Please have a look at “Mapped Parameters” at the end of the parameter section as well to learn how to use images to control the value

Escape strength

It is often necessary to use a higher “Approach strength” to make the particles quickly approach the target object, but this might lead to unwanted overshooting. With “Escape strength” this effect can be drastically reduced, because it counteracts the attracting forces. The fluid calms down faster and the target shape is reached in less time. With high settings you can probably observe orbiting particles. Like its counterpart, “Escape strength” also offers the usage of bitmaps. Please take a look at “Mapped Parameters” at the end of the parameter section as well to learn how to use images to control the value.

Magic strength

This parameter determines the strength of the attraction force introduced by the object. Larger values accelerate the shaping process and the particles will better match the underlying 3D model.

Magic Mode

The daemon provides two options. “Nearest Face” is the most commonly used mode and causes the particles to travel to their nearest polygon. With “Random Face” you can introduce a turbulent distribution of the particles.

Random within Face

You can choose between “Yes” and “No”. When this option is activated the particles will constantly change their position over the object’s surface. This mode is also called “dancing mode”.

 

Mapped Parameters

You have already read that several attributes can be represented with image maps – here is some additional information. Image maps create areas of different influence, based on the stored colours. The adjustments are made from a separate window, providing all relevant parameters and switches to make use of this new feature. An additional function is that you are even able to load image sequences for animated parameters. Dark areas indicate zones with low values, while white represents the maximum.

 

 

Especially larger objects can strongly profit from this feature. You can, for example, create a river bed with low “Particle Friction”, while the outside areas have higher values. All this can now be painted to a map and then projected onto your object. This does not only work with RealFlow’s native items, but also with imported objects from SD files. It is important that imported objects carry (correct) UV coordinates.

It is even possible to make the used map or image sequence visible in RealFlow’s viewport. If you cannot see it or work with multiple maps for different parameters you can easily to show the desired map with:

Display > Texture > [ Map type ]

If you want to replace the fixed value with an image map, please do the following:

  • Right-click on one of the parameters with a chess board icon.

  • Choose “Load Texture” from the context menu.

  • RealFlow opens a new window called “Load Texture for Parameter”.

  • Fill out the dialogue and confirm your settings with “OK”.

 

File

You can load one or more image files with TGA, BMP, JPG, PNG or TIF format. The path to the image is shown under “File”.

 ...

With this button it is possible to open your OS’s file picker. The images must be coloured – either 8 bit, or if supported, also 16 bit. Image sequences are recognized automatically and you do not have to select the first and the last frame. All files with an equal padding are loaded to the canvas.

Channel

Here you can choose one of the picture’s RGB channel. The currently active channel is shown in the canvas and updated according to your selection.

Min. value / Max. value

These values represent the pixels’ default intensities. They are spread over the available minimum and maximum range of a parameter but, in case of need, this range can be clipped by entering new values. The shades of the image channel are then spread over the given settings.

Min. frame / Max. frame

Both parameters are important for image sequences. You are able to specify a certain frame range that is used for parameter mapping. Simply enter the desired start and/or stop value and the frames outside of this range will be ignored.

FPS Ratio

When this parameter is set to 1 the image sequence is played at its original speed, e.g. 30 FPS. If you want to achieve faster or slower playback then you have to change "FPS Ratio" accordingly. Values above 1 will increase playback speed; smaller values are used to slow it down. If you do not want to start with the first frame of your sequence, you can determine an “Offset” from which the series will start playing.

Loop

The option creates an infinite back and forth loop from the currently loaded image series.

Control Buttons

They work exactly as in other video player. You can go to the first or last frame, to the previous or following frame, and start/stop playback. The slider allows you to scrub through the entire sequence and jump to a certain frame.

Skip

This option is related to “FPS ratio”: while playing back an animated sequence, RealFlow cannot always achieve the given FPS rate. By checking “Skip”, RealFlow will play the image sequence with the adjusted FPS rate, but some images might be dropped. Without “Skip”, RealFlow shows all images, but there is no guarantee that the desired frame rate can be maintained.