Anchor point problem- need help urgently

Hi, I am very new and to and struggling with an assignment on grasshopper. Right now i need to use the plug in kangaroo and have so far managed to blow up a hexagonal grid using springs and u-force. Now i was hoping to select certain anchor points around the edge and remove them (I tried baking the start and end points out and then manually choosing the ones i wanted and referencing them back into grasshopper into the anchor points connection, however it didnt turn out how i wanted). I have included an image of my grasshopper file and rhino file. This is what i have done so far.

I have also included a picture of what kind of thing i am attempting to do, i understand i cant make it look 100% like this with the kind of grid i have started with, however i wanted to be able to create these arch like structures, by selecting only certain anchor points. But when i select only certain anchor points the geometry instead of releasing upwards (like in the second image-the image i am using as inspiration) like i expected, it goes crazy and collapses inwards (as seen in the 3rd picture where i have baked the points out and chosen some of them to take away, then plugged these chosen points into anchor points)

Sorry if this is a dumb question, my understanding of how grasshopper and kangaroo work is very low. I really need help to achieve this, and would really appreciate any suggestions anyone has.

Thanks

Attachments:

Grasshopper- 1.png, 441 KB
597f93d74257b6e0a490d58e7a79fd05 (1).jpg, 55 KB
Grasshopper 2.png, 437 KB

Replies to This Discussion

Permalink Reply by Riccardo Majewski on May 9, 2015 at 8:03am

It would be really easier to help you if you upload your definition with ALL inputs as internalized data or with also .3dm file attached. (but better internalize)

In the meantime you can try:

- use the "combine&clean" component to possibly "fix" your mesh before linking it to the others 4 components;

- "remove duplicates" component to your anchor points, maybe some duplicates causes the error;

(you are trying to use endpoints of EVERY ege, surely it will be all duplicates)

- flatten every inputs in main kangaroo component.

Try this.

For better help, attach your definition.

Permalink Reply by Nicole Dowling on May 9, 2015 at 9:09am

Thanks for your reply and suggestions. I have attempted the suggestions you gave, but havent had any luck unfortunately. I have attached the grasshopper definition if that makes it easier and id love to hear any other ideas you might have?

Attachments:

Assignment 2.3- kangaroo.gh, 14 KB

Permalink Reply by nikos tzar on May 9, 2015 at 11:29am

Hello Nicole,

Baking the points and referencing the ones you want back to GH should work... (as long as we are talking about the points of the mesh before it enters kangaroo)

Anyway, here is another way you could do this:

Get all the mesh vertices, cull duplicates and keep just the ones that are near some user-defined points and use those as anchor points. (always reset kangaroo before changing/moving these points).

Attachments:

anchor-points.gh, 17 KB

Permalink Reply by Nicole Dowling on May 9, 2015 at 8:46pm

Thankyou so much! This is exactly what i wanted. I think the reason my mesh was going crazy was that i was forgetting to reset kangaroo each time, such a simple mistake, thankyou for that suggestion. The file you have attached is also really helpful. Thankyou so much, you have really saved me.

I was also wondering if you might have any ideas for how i could get the smaller hexagonal cuts in the mesh that are shown in my precedent image (the second image). I was thinking of using the offset tool on the original hexagonal grid, but im not sure where to go from there.

Permalink Reply by nikos tzar on May 10, 2015 at 7:42am

Hello Nicole,

Weaverbird plugin has some components to easily create what you want:

Permalink Reply by Nicole Dowling on May 10, 2015 at 9:23am

thanks that was also really helpful. But do you know why each hexagon is dividing in half and then making an offset cut for each half? Is there a way i can stop this and just have 1 offset cut out per hexagon?

Thankyou for all your help, i really really appreciate it. Do you know anything about attractor points? If you do, is there any chance you could take a look at my other discussion i just posted?

Permalink Reply by nikos tzar on May 11, 2015 at 9:37am

http://www.grasshopper3d.com/forum/topics/hexagonal-grid-to-meshes

http://www.grasshopper3d.com/forum/topics/hexagonal-mesh

Hello Nicole,

you can check out the above discussions to better understand why your mesh faces get subdivided. ng5 alex provides a workaround that might be useful in your case (1st discussion).

Permalink Reply by Nicole Dowling on May 12, 2015 at 9:28am

Thanks so much for all your help, i really appreciate it, you really helped me to be able to finish my assignment :)

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