Forums Houdini Indie and Apprentice How to create a surface around a hole

How to create a surface around a hole

   3988   6   2
User Avatar
KevinBockelandt
Member
2 posts
Joined: 12月 2018
Offline
 
Hello !

I am trying to model a very basic traffic cone. So I used a tube for the cone with a PolyExtrude, then a clip to make sure the bottom is perfectly flat. It leaves me with hollow sides at the bottom:



To close the geometry I first tried a PolyFill, but the node does not create faces between the outer and the inner circle. Instead it treats them independently and it results in 2 sets of circular primitives overlapping:



The closest I got to what I want is with the PolyLoft node. By specifying the outer circle and the inner one as 2 different sets of points. But for some reason there are some strange artefacts occurring, and I can't get rid of them.



Now I could solve the problem by hand with a TopoBuild node but it's not really ideal since I lose the whole procedural aspect.

What would be the best way to recreate the missing geometry and close the polygon in this case ?

ps: the file ->
Image Not Found

Attachments:
traffic_cone.hiplc (76.3 KB)

 Report
User Avatar
sjooons
Member
4 posts
Joined: 10月 2018
Offline
 
I'm not sure this is the best way to do this (I'm very much a noob when it comes to 3d modeling), but instead of using the clip node, I would select all the points you want to have a the same height, and then use an “edit” with 0 in the y-scale.

Attachments:
traffic_cone.hiplc (71.2 KB)

 Report
User Avatar
bobc4d
Member
320 posts
Joined: 5月 2016
Offline
 
if you take a tube, make polygon, select points and grab all top points, use scale and scale them in, then poly extrude a little make sure to select output back and the bottom of tube (cone) should be flat. you can get creative and polybevel the top and bottom of cone so it isn't so sharp, edge loop a bit from bottom, select those faces and extrude them out to give you a flat bottom surface. . . .

I attached the file I made in Indie.
Edited by bobc4d - 2019年3月21日 19:38:55

Attachments:
traffic cone.hiplc (70.3 KB)

 Report
User Avatar
gmanyyz
Member
44 posts
Joined: 1月 2017
Offline
 
Hi Kevin,

I would do something like this:

1. Make the cone as you did by using a primitive type polygon tube.
2. Do not check the “End Caps”
3. Select the bottom edges and then choose “Polyfill”. Single Polygon is fine (Fill Mode)
4. Create the thickness by highlighting all polys and then choose “PolyExtrude”. Use positive amount towards the outside.
5. If you are going to be using subdivision to smooth it out, you'll need some edge loops around the edges you want sharpened. On the bottom, I did select the one polygon and then chose “PolyExtrude” but used “Inset” to get that edge loop from the outside edge.
6. File attached. Indie.

EDIT: IF you don't want that bottom part solid, then skip #3 and go right to PolyExtrude!
Edited by gmanyyz - 2019年3月21日 23:13:17

Attachments:
Cone_test.hiplc (129.2 KB)

 Report
User Avatar
KevinBockelandt
Member
2 posts
Joined: 12月 2018
Offline
 
sjooons
I would select all the points you want to have a the same height, and then use an “edit” with 0 in the y-scale.

Yes, it's actually much simpler than what I wanted to do. Still a little surprised that there is no obvious way to recreate the missing geometry though.

Thanks for the answer!
 Report
User Avatar
jsmack
Member
7741 posts
Joined: 9月 2011
Offline
 
Although avoiding the problem to begin with is the best solution, sometimes you just need to bridge a gap. For that there is polybridge:

Attachments:
polybridge.JPG (130.7 KB)

 Report
User Avatar
Konstantin Magnus
Member
670 posts
Joined: 9月 2013
Offline
 
Polyextrude also accepts normal directions. Just flatten the intrinsic normals, export them as a new attribute like ‘dir_extr’ and feed this into the extrusion mode set to ‘normal’.
Edited by Konstantin Magnus - 2019年3月25日 03:12:25

Attachments:
cone_extrude.jpg (20.7 KB)
cone_extrude.hiplc (159.3 KB)

https://procegen.konstantinmagnus.de/ [procegen.konstantinmagnus.de]
 Report
  • Quick Links