Why is there a gap between the particles and the collision object?
RealFlow | Cinema 4D uses an internal proxy representation of a collision object – the so-called collision geometry. In order to refine this proxy object you have to add a → "Volume " tag and decrease → "Cell Size" or choose a better → "Collision Geometry Detail" option. You can also control the shape and look of the poxy through the → "Collider" tag's "Show Collision Geometry" option.
If your object is an open, single-sided shell then you will always see a more or less small gap between the object's surface and the fluid. The reason is that RealFlow | Cinema 4D creates a layer around such an object to make it watertight.
Why are simulations with point level animated objects (PLA) slow?
With PLA-enabled objects, RealFlow | Cinema 4D has to recalculate the internal collision geometry with every single simulation step. Especially with small → "Cell Size" values PLA can be a simulation's bottleneck.
I can see particles going through my collision object. What's happening here?
With fast moving particles and/or a very small number of simulation steps per frame it might happen that a particle in a starting position goes to a final position in the next simulation step that is at the other side of the collision geometry:
- To avoid this, activate the "Collider" tag's → "Continuous Collision Detection".
- By default the auto mode is enabled, and RealFlow | Cinema 4D will decide automatically, if the collision object requires "Continuous Collision Detection".
- Collision detection is computationally more intensive, and simulations take longer.
- In some cases the automatic detection fails, and you have to disable enable "Continuous Collision Detection" manually.
I have enabled "Continuous Collision Detection", but there are still particles going through my collision object. Why?
If this is the case the problem can be fixed by
- increasing the number of → simulation steps (aka "substeps")
- changing the "Volume" tag's → "Volume mode" to "Shell"
- increasing the "Volume" tag's → "Surface offset".
Why can I see the wetmap in the render, but not in the viewport?
Open the → material panel and go to the "Editor" section. Then enable "Animate Preview...".
I have activated the "Animate Preview..." option, but still I cannot see the wetmap. Why?
Wet-dry maps require an UVW tag attached to the object. You will get this tag automatically when you make your object editable.
The wet map is distorted, mirrored or repeated. How can I fix this?
Wet-dry maps require proper UVW coordinates and this is within your responsibility. RealFlow | Cinema 4D does not perform any changes on UVWs or plausibility checks.
I have applied an object to the "Object" emitter, but there is no emission. What's wrong?
When the body's polygons are very small it might happen that you will not get any particle emission. To fix this, increase the "Fluid" container's "Resolution" parameter to create more particles. You may need high settings (100, 200 or even more).
Are RealFlow | Cinema 4D particles able to influence Cinema 4D dynamic bodies (rigid and soft bodies, cloth)?
No, RealFlow | Cinema 4D does not change the motion or shape of Cinema 4D dynamic bodies, but they are able to collide.