Sub Curve. How do I get both sides of the Elipse I "split"?

Replies to This Discussion

Permalink Reply by Damien Alomar on September 18, 2009 at 8:34am

I'm not sure why that's being done. The "solution" is to use the Shatter component and pass the two parameters in from Line/Curve intersection. The only problem with this is that since the line probably does not intersect through the exact start point, you will actually get 3 curves one from the start point to the first split parameter, a second between the supplied split parameters, and one from the last split parameter to the end point.

You can get around this by joining the two smaller segments, which involves sorting the curves by length, joining the 2 shortest ones, then merging the other curve back into the stream.

HTH

Attachments:

• splitClosedCrvIn2.ghx, 124 KB

Permalink Reply by Theunis du Toit on September 18, 2009 at 12:42pm

Thanks for the reply, your reasoning is right, the purpose is actualy to split it which I did and luckily the two short curves are always the same numbers in the list so a default selection number can be used and no conditional statements are needed to select them and join.

But in the future I think I will want to, for whatever reason it may be, be able to select that other Sub Curve. And it bugs me that I can't do it now.

Thanks for you reply.

Permalink Reply by Damien Alomar on September 18, 2009 at 2:12pm

Yea, something's up with sub curve...it might be "auto sorting" the domains, which is "good" for non-closed curves, but for closed curves it actually makes sense to go from a higher parameter to a lower one.

There really aren't any "conditional statements" within that definition, but my personal advice would be to leave it as is and let it always be right as opposed to potentially causing incorrect results if the structure of the geometry changes. Parametric solutions tend to be much more resilient when they don't make assumptions about the structure of data.

Permalink Reply by Theunis du Toit on September 18, 2009 at 3:19pm

Yes what I meant to say was setting the definition up that it will always select the two short curves to join. I tried testing it by moving the line and elipse around atempting to create all posible future scenarios and the result remained consistant (for now), but yes I will remain aware of it incase something goes wrong.

cheers

Permalink Reply by veronica arcos on September 21, 2009 at 5:02am

Try intersetcing the line with elipse, u ll get the intersection points, then use the shutter component to split the line, so instead of curves u use points to split the line.