Why does the orientation of my construction plane rotate at a random point along this curve?

Replies to This Discussion

Permalink Reply by Shawn Swisher on June 23, 2015 at 10:07am

I've added another picture to hopefully explain the issue a little more clearly. The steel angles of this shade structure should all be at a consistent orientation, but you can clearly see on the lower portion about halfway across the image that the orientation angle changes for seemingly no reason. I've already rebuilt the curve several times and that doesn't seem to help.

Permalink Reply by peter fotiadis on June 24, 2015 at 12:12am

Well ... I could use C# to completely control planes in every imaginable way ... but this is a very simple case, so let's start from the basics (and then continue further on):

do these planes "comply" with twisting issues? or you want something else?

Attachments:

• Planes_along_curves_V1.gh, 39 KB

Permalink Reply by Shawn Swisher on June 24, 2015 at 9:20am

Peter,

Thanks for replying. I was able to create PFrames much in the same way you did, and even got the lines I needed to use as an extrusion vector. The problem is that when I go to extrude, the plane that it extrudes from is shifted in certain areas. Take a look at what happened when I added some frames normal to the lines you had created in your script:

See how the plane normal to the line just shifts all of a sudden? For what I need, it doesn't matter which direction the plane is rotated as long as it's normal to the line and the same everywhere. As soon as it rotates it throws off the consistent orientation of my shade structure.

I hope I explained that clearly. Do you have any thoughts on how to get that to be the same orientation?

Thank you for your help!

Permalink Reply by peter fotiadis on June 24, 2015 at 10:31am

My dear Watson,

This is NOT the way to do it.

More ASAP (appears that the trad V2 update is unavoidable - what else?, he he)

Permalink Reply by peter fotiadis on June 24, 2015 at 11:26am

Try this V2 (Note: used a test profile and the loft to indicate the obvious).

BTW: Making zero twisted planes (but the 1M Q is: in relation to what?) in other situations (and in this one as well ... if you follow the "standard" way, as you did) is impossible without code (C#, aka the Dark Side), but the good news are that you can do whatever you want.

Attachments:

• Planes_along_curves_V2.gh, 52 KB
• Planes_along_curves_V2.3dm, 174 KB

Permalink Reply by Shawn Swisher on July 2, 2015 at 12:28pm

This is very close to what I was trying to achieve, but not quite. The primary difference is that instead of having a single curve and taking the normals directly from the curve (as your definition does) I have a lofted surface made from two curves that are out of plane with each other, and the extruded shapes need to basically be in line with that lofted surface. I was able to create those shapes in line with the surface, but as you can see in the images above the construction plane just shift along the curve, making some of the extrusions rotated along its z-axis. Not sure if that explains it any better or if I'm just continuing to make little sense.

Luckily, I think we're moving away from this facade design and onto something else, though I would like to figure this out since it seems like it should be an easy fix.

And I do really appreciate your help, Peter!

Permalink Reply by peter fotiadis on July 2, 2015 at 11:26pm

As I said, I should switch entirely to C# to control anything with these $@%$ planes.

I'll post soon some (over)simplified version from the stuff that I use frequently on that matter.

Permalink Reply by peter fotiadis on July 3, 2015 at 1:58pm

So, let's start from the basics:

This very entry level C# (without extensive "checks" : just a simple tech-preview) corrects (rotates) perpendicular planes in such a way that their X axis is the intersection of the lofted Brep with the original perpendicular plane.

Obviously the possibilities are unlimited with regard any imaginary "constrain" condition.

BTW: use the negAngle bool with crv1: what happens? he, he

best, Peter

Attachments:

• PlaneControl_along_curves_V1.3dm, 66 KB
• PlaneControl_along_curves_V1.gh, 301 KB

Permalink Reply by peter fotiadis on July 4, 2015 at 1:47am

Spend a couple of minutes more on that one: the trad V2 update, that is.

Have fun

Attachments:

• PlaneControl_along_curves_V2.3dm, 61 KB

Permalink Reply by peter fotiadis on July 4, 2015 at 1:47am

Oops

Attachments:

• PlaneControl_along_curves_V2.gh, 311 KB

Permalink Reply by Joseph Oster on July 2, 2015 at 2:17pm

I added a slider that shows the base plane and vector at the series of start points; it's very clear where it rotates ninety degrees at the turns (note red and green X/Y axes).  But look what happens if you plug in a X, Y or Z vector instead of your angled vector:

Attachments:

• ScrimStudy_ghdef_angles_troubleshoot_2015Jul2a.gh, 38 KB

Permalink Reply by Joseph Oster on July 2, 2015 at 4:06pm

This one replaces the 'Plane Normal (Pl)' you were using with 'Horizontal Frames (HFrames)' and seems to handle those curves well?

Attachments:

• ScrimStudy_ghdef_angles_troubleshoot_2015Jul2b.gh, 39 KB