In this tutorial you will learn how to make use of RealFlow's “MultiPoint” option to boost the number of particles and render a dense foam cloud. Here, a RealWave scene with an emerging and splashing object will be used, but the workflow is valid for any other particle source.
Custom materials can only be created and edited with the Maxwell Material Manager and you require a valid license of the Maxwell Render Suite. Materials from other applications do not work. Simple image maps from an object's “Texture” panel are not rendered as well.
Shading RealWave Surfaces
Select the “RealWave01” node and go to its → “Node Params” panel:
- Maxwell Render > Material > water_ocean
- Display shelf > Fire
What you get is a more-or-less transparent surface – a result that is everything, but ocean-like. To change this we need more contrast and this can be achieved with a simple ground plane:
- Close the → “Maxwell Interactive” window.
- Object shelf > Plane
- Scale the plane with R key. The plane should have similar dimensions as the RealWave surface.
- Move the plane below the surface with the W key. Make sure that it does not intersect the waves.
- Display shelf > Fire
- Now the water looks realistic and like an open ocean.
If you want to extend the ocean increase the number of tiles change
- RealWave01 > Node Params > Display > Maxwell Render > Tile 1 | 2
- Extend the ground plane accordingly.
- With larger numbers of tiles you will most probably see repetitions in the wave pattern.
Shading the Soda Can
Since this is a custom object, RealFlow does not provide a ready-to-use material definition. But, the render engine does only accept so-called MXM files (Maxwell Material). If you do not own a valid license of Maxwell Render we recommend downloading the demo version from
http://www.maxwellrender.com > Try
In order to apply the material go to:
- Soda Can > Node Params > Maxwell Render > Material > From File
- @ Material File > load your MXM material with the can's texture
Splashes and Foam
Here, the splash simulation consists of 400,000 particles. Not bad, but by far not enough for a good foam render. In Hybrido simulations, for example, we normally have millions of particles. Re-simulating with higher emitter “Resolution” settings is not really an option, but what can be done to boost the number of particles? The answer is the “RW_Object_Splash01” emitter's “MultiPoint” option. An option that is available for every particle emitter.
Here is how it works:
- Go to RW_Object_Splash01 > Maxwell Render
- Every existing particle will act as a seed for additional particles. The number of extra particles is defined under “Multipoint”. With 10 you will get 10 new particles per existing particles, for example.
- The new particles are added within a (virtual) sphere around an existing particle. The size of this sphere is controlled via “Dispersion”.
- The actual size of the existing and the new particles is determined with “Radius”. This means that you can adjust the particles' size with this parameter even if “Multipoint” is not used (= 0).
The pre-adjusted values for “Dispersion” and “Radius” give good results in many cases. If you want to change these settings please use similar values for “Dispersion” and “Radius”. With large “Dispersion” settings you will see unnatural cloudy structures.
- The creation of MultiPoint particles is procedural and hence very fast.
- Try to achieve a total number of several millions of particles. In this example, a value of 35 gave satisfying results.
- MultiPoint particles are not saved and do not change the cached particle files.
- MultiPoint particles are a good method to boost foam and splashes, but they cannot fix everything.
Finally, add the downloaded (or self-created) “Foam.mxm” material definition to the emitter:
- Maxwell Render > Material > Foam
- Display shelf > Fire
The scene's lighting and render quality is controlled under
- Display shelf > Maxwell Scene Preferences
- Go to “Light”, drag the slider, and click on “Apply” to see you changes in realtime. If you are not happy, simply readjust the time, and renew the preview with “Apply”.
- Image Quality > 100%
- Max Sampling Level > 12 (can be higher as well, but takes more time)
- Engine > Production
- Motion Blur Factor > higher settings create longer streaks
- Once you have found your settings, click on “OK”.
For a complete render, a few more preparations are needed:
- Display shelf > Camera
- Switch to the camera's view with the 5 key.
- Display shelf > Maxwell Preview
- The render starts.