Make a Zig Zag curve along brep faces?

Hello everyone,

I am trying to generate a zig zag path along a brep faces. This zig zag path needs to have a constant slope, x slope.

I was able to achieve a very basic path using contour lines, but it ends up being pretty manual and does not adapt well to more than 1 face of the brep, plus the slope is wrong because it increases as the path goes down (as height is the same because of contour but distance traveled is shorter, so steeper path).

Any help is greatly appreciated.

Shynn.

Attachments:

Zig Zag.gh, 14 KB

Replies to This Discussion

Permalink Reply by Joseph Oster on September 9, 2017 at 6:50pm

The 'Slope (degrees)' slider is used to calculate the radius of a cone with its tip at the starting point. The yellow line is the 'BBX' intersection of the cone with the sloped surface segment - guaranteed to have the same slope set by the slider.

So you could iterate (with Anemone) and move the cone's tip to the other end of the yellow line to find the next "switchback" in the path. Not necessarily trivial, esp. if you want to traverse adjacent sloped surfaces.

Attachments:

ZigZag_2017Sep9a.gh, 23 KB

Permalink Reply by ShynnSup on September 9, 2017 at 8:01pm

Okay very smar Joseph!

Tried, it, but the loop aint working for some reason, do you know why? (I did double click to run it).

Attachments:

ZigZag_2017Sep9b.gh, 75 KB

Permalink Reply by Joseph Oster on September 9, 2017 at 8:41pm

For one thing, 'BBX' appears twice inside the loop and it appears you are passing the curve instead of the cone to 'Loop End D0'. Fixed that and then noticed the cone was moving off in only one direction instead of going back and forth - so fixed that using 'Mod (Modulus)' on the loop counter to control a 'Stream Filter' based on odd/even. It works!

Attachments:

ZigZag_2017Sep9c.gh, 78 KB

Permalink Reply by ShynnSup on September 9, 2017 at 9:16pm

Outstanding Jospeh, thank you!

Permalink Reply by Joseph Oster on September 10, 2017 at 7:46am

I made a few improvements, including multiple surfaces:

Attachments:

ZigZag_2017Sep10a.gh, 25 KB

Permalink Reply by ShynnSup on September 10, 2017 at 10:54am

Woa beautiful, thank you Jospeh, that was all I needed.

Permalink Reply by ShynnSup on September 20, 2017 at 6:51pm

Joseph, little inquiry that I wasnt able to solve... Hopefully you can help me.

I moved the starting point of the cone up in z, (vertex of the brep), but it does not seem to work alright then.

Attachments:

ZigZag_2017Sep10b.gh, 24 KB

Permalink Reply by Joseph Oster on September 20, 2017 at 8:11pm

Sorry, the "Pottery Barn rule" applies: "if you break it, you own it".

Seriously, one error seems to be how you are trying to move that point?

Original:

Your version today:

Recommended:

But it still appears to be broken... Pottery Barn rule.

Attachments:

ZigZag_2017Sep20a.gh, 25 KB

Permalink Reply by ShynnSup on September 20, 2017 at 8:13pm

Okey, thought you might have a better understanding of why it wanst working, will look into it, still thanks!

Ps: You can move points with move or adding z values to its coordinate (basically the same).

Permalink Reply by Joseph Oster on September 20, 2017 at 9:04pm

By reducing the Z 'Factor' to 8 and the loop 'Repeat' limit to 2, I think I figured it out. But I still think you need to "own it". Basically, the 'Vec2Pt' used to 'Move' the cone inside the loop uses the end points of the 'BBX' curve/line. BUT, that's not where the cone really is! The first 'BBX' curve starts half way across the top of the panel, while the tip of the cone is at the raised starting point, so the loop is moving it only ~half way across...

I don't quite remember why I'm using that 'Sort' except that it facilitated multiple panels?

Pottery Barn rule still applies.

P.S. Maybe it will still work if you move the starting point horizontally across the top of the panel instead of vertically?

P.P.S. Like this - but no, that creates a different problem, since the cone intersects in both directions: