Surface extrusion

Replies to This Discussion

Permalink Reply by Joseph Oster on January 3, 2016 at 5:34pm

Offset surface and lofted edges with Brep Join to create Closed Breps?

Attachments:

• infarch_2016Jan3a.gh, 18 KB

Permalink Reply by Ethan Gross on January 3, 2016 at 5:38pm

Here we are with an extrusion but in general none of the cross sections, except at the center, will be rectangular. For that, you'll need a sweep. The extrusion direction is taken as the normal evaluated at the the center of the surface.

Attachments:

• infarchextrude.gh, 17 KB

Permalink Reply by Joseph Oster on January 3, 2016 at 6:17pm

Plugin version: 0.9.0076

Missing object chunk in archive. An object could not be found in the document,it will be missing once the file is loaded.

P.S.  It looks like both of us lost the Image Sampler embedded in the original file?

Permalink Reply by Ethan Gross on January 3, 2016 at 6:37pm

Thanks Joseph. I've tried this twice now. It looks fine on my screen and after I save it, leave Rhino, walk around the block, I get the above message. I get this with your def also. Any ideas? Is it that the original def is from an old version of GH? My other stuff seems OK.

P.P.S. You're right about the image sampler! - yet it does load up when you look at the original though. Very strange.

Permalink Reply by Joseph Oster on January 3, 2016 at 6:56pm

You can copy the Image Sampler from the original file and "Past In Place" for either your file or mine, then reconnect its output to the 'V' input of 'ReMap' - works fine again!  I don't know how to save it with a modified file?  Anyone?

Ethan, I believe the offset surface approach I used works better in this case than extrude.

A two rail sweep of an end rectangle would also work, but making those end rectangles is another challenge.

Permalink Reply by Ethan Gross on January 3, 2016 at 7:02pm

Joseph,

I did paste in the image sampler and yes, it works but the same problem arises when I save. I agree your approach is better in general, since presumably these slats would have a rectangular cross section but I did what was asked. The poster's problem was with extruding.

Permalink Reply by Wujo on January 4, 2016 at 2:18am

Hello,

Thanks to both of you! Both definitions do the job :).

As for image sampler I also had some problems embedding the image before posting definition here for some reason.

Once again thank you for your time and help

Have a nice day

Permalink Reply by Joseph Oster on January 4, 2016 at 5:56am

So how did you solve the problem of keeping the image sampler embedded in the file?

Let's be perfectly clear here - while both definitions "do the job" and you did ask about extrusion, the offset surface is by far the superior solution when working on a compound surface like this.  There are cases where you don't see much difference between extruding and offset but this isn't one of them.  The twisted surfaces get way out of alignment with the extrusion direction and get obviously distorted cross sections as a result.

The other option you mentioned of sweeping profile curves along two rails (the long edges of each louver surface) would also produce an excellent, undistorted closed brep.

Permalink Reply by Wujo on January 4, 2016 at 6:15am

Joseph,

I changed image file location to desktop and relinked it to image sampler. Previously, after saving, neither image sampler nor image itself were within the file. I have no idea why it happened.

Both solutions "do the job" since for my use (rendering) these are more than enough :). I just started creating definition that way and although i was aware that sweeping rail would also work I wanted to know how to make the definition work that way (curiosity :) ).

Once again thank you for your time and support