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- Create a standard Cinema 4D cylinder and make it editable.
- Switch to "Points" mode, select the caps' vertices, and drag them apart.
You will notice that
As shown in the image the caps can be moved separately. This means that they are not connected with the rest of the cylinder, and RealFlow | Cinema 4D treats the cylinder as an open object that cannot be filled!
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- If you want to keep the cylinder's parametric state you have to drag the "Connect" object the → "Fill" emitter's Emission > Body field in order to fill it with particles.
- Alternatively it is also possible to make the connect-cylinder group editable.
- Another method is to activate the cylinder's "Fillet" option.Then set "Segments" to 1, and "Radius" to 0.001.
Using a connected parametric object with the "Fill" emitter.
Is the Object Closed?
Only completely closed objects can be filled. If an object is open somewhere - even if it is just a single polygon - it is no longer possible to differentiate between inside and outside and treats the object as a single-sided shell. In plain and simple words: you cannot fill polygons. Only objects with a volume can be filled, and this requires that their geometry is closed.
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