I am dealing with a big uncertainity when generating fabrication data. I have a ruled surface that I need to unroll. There are many openings (letters) in that surface that have to be unrolled together with the surface to be laser cutted.
I’ve noticed that when I unroll curves together with the original surface, I get a different result than when I map curves to previously unrolled surface (which is a waaaay faster approach). First, I assumed that UV space is the same for both approaches, but it is not (verified by measuring edge lengths of source and unrolled srf).
Hello Pascal. I was assuming that the UnrollSrf is not UV destructive. Didn’t know about UnrollSrfUV as I was using Grasshopper. I tried to verify that UV is matching by mapping edge curves (FlowAlongSrf) and it was just fine. There was no reason not to trust the component, as majority of components keep UV space as is down the stream.
Now all unrolled parts are already laser cutted and I am facing a terrible and expensive issues thanks to that distortion. I wish I knew this before. There should be some sort of warning message… What do you think?
Yes. This one edge is already distorted and it’s the trimming curve. But in grasshopper, I was working with the original Untrimmed surface (I was even thinking that the trimming might cause some issues so I tried to avoid it as much as possible.
Don’t you know why V direction stays undistorted?
Possible warning should be an amount of distortion? This could possibly be done by unrolling the surface together with some points and comparing them with the same points just by evaluateSrf - and measuring the distance of the result. The value informs the user about possible distortion (and also where that happens). Knowing that issue before, I’d do this and avoid the problem completely.