Hi Pilou - there are 2 modes for sweep, "auto-place", and "non-auto-place".

Right now the mode is determined depending on whether the shape curves have any point of them inside the bounding box of the rail curve.

So imagine a box around the rail curve - if your profile shapes are inside that box (as one of them is in your file, the one that is closest to it), then MoI will not move your shapes around and will sweep them in their current orientation.

If all your profiles are outside of the box around the rail curve, then MoI will use "auto-place" mode and will rotate and place your curves perpendicular to the rail. This is a useful mode for doing things like a tube or pipe type shape quickly.

So if you want to use auto place mode to have them automatically moved perpendicular to the rail, make sure your profile curves are a little distance away from your rail curve and not next to it.

I would like to figure out a way to make this mode have some kind of switch or more controllable option, right now it is sort of hidden.


> Sometime it's "flat", sometime it's good ???

The "flat" ones are the ones that included the shape curve that was inside the box around the rail. MoI will not move your shapes around if they are closer to the rail because it assumes you may have placed them in a particular position.

Let me know if you need more details on this.

- Michael