topic Re: Is this a bug or simply a sketch solver problem in Fusion Design, Validate & Document Forum

Is this a bug or simply a sketch solver problem

cekuhnen — Thu, 01 Aug 2019 13:52:38 GMT

making a spline G1 to a line works well when later adjusting the spline

When however you use G2 the spline shape radically changes after the other spline end point will be moved.

From a usability stand point this makes somewhat zero sense.

So what is happening here internally that makes Fusion change the G2 result so drastically.

I never saw this in any other CAD app.

https://drive.google.com/file/d/1VMObOdRDlJh9bsqyZqPxzRmdMAWZxfDR/view

Re: Is this a bug or simply a sketch solver problem

TrippyLighting — Thu, 01 Aug 2019 14:12:48 GMT

This was easy to reproduce and I'd say that's a bug.

Re: Is this a bug or simply a sketch solver problem

jeff_strater — Thu, 01 Aug 2019 14:24:33 GMT

@cekuhnen, @TrippyLighting - can you share a design that shows this? I just tried, and it seemed to work OK for me

Re: Is this a bug or simply a sketch solver problem

TrippyLighting — Thu, 01 Aug 2019 15:04:50 GMT

@jeff_strater no, actually it did not ;-)If you look at the length of the g2 tangent handle you'l see that it changes as soon as you move that point. The effect in your case (and in what I tried is simply not as strong as in @cekuhnen's. are but it is present.

If that screencast I made ever completes conversion I'll post it. its very visible there.

Re: Is this a bug or simply a sketch solver problem

jeff_strater — Thu, 01 Aug 2019 15:25:24 GMT

In my case I see a small change. The tangent handle goes from 95 to 97. It's a little surprising, but there may be reasons for this. Remember, the tangent handle lengths are somewhat arbitrary and not precise. But, I would still like to see a model where this change is large, so the sketch team can look into it.

Re: Is this a bug or simply a sketch solver problem

cekuhnen — Thu, 01 Aug 2019 15:31:22 GMT

Hi Jeff

here is the file - it seems this is related to when the tangent handles are not activated.

anyway - did I say sketching in Fusion is a pain ? ...

Re: Is this a bug or simply a sketch solver problem

TrippyLighting — Thu, 01 Aug 2019 15:33:02 GMT

Re: Is this a bug or simply a sketch solver problem

jeff_strater — Thu, 01 Aug 2019 16:48:40 GMT

Thanks, @cekuhnen & @TrippyLighting . That's what I needed. I'll have the sketch team look into it.

[edit] I created FUS-52818 to track this

Re: Is this a bug or simply a sketch solver problem

cekuhnen — Thu, 01 Aug 2019 16:52:28 GMT

@jeff_strater @TrippyLighting

No worries Jeff - this is actually a quite old issue I encountered in the past. Just checked my old test files where I logged it.

when you chat with the sketch team you can als bring up a similar issue with cv curve which act like having brain seizures when Moving cvs. For cvs you fully have to constrain every detail to stabilize it making this a painful experience and labor intensive work flow vs working with less fit points.

that issue is also present since cv splines were released