Clipping is a very effective and convenient way of reducing a mesh’s size. Whenever there are invisible parts they should be clipped. Try to use objects which are as simple as possible with even surfaces (cubes for example) because complex objects will only increase mesh creation time!
Clipping objects
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You can decide which “side” of the clipping object should be used. “Inside” uses the object’s volume and everything inside it will be cut away. “Outside” clipping deletes all polygons outside the used node. Open parts or holes are not filled with polygons and the result is a closed an open mesh.
Camera clipping
This option needs a camera, of course. It makes no difference whether the camera is imported or native – both types can be used. “Camera clipping” cuts away everything that is outside the currently adjusted field of view. That is something like WYSIWYG – “What you see is what you get” – and also works with animated cameras.
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