Delgine 3D Tools & Content DeleD Community Edition
Forums
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Tutorial: Welding a cylinder to a plane

 
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    DeleD Community Edition Forum Index -> DeleD Tutorials
View previous topic :: View next topic  
Author Message
chronozphere
DeleD PRO user


Joined: 20 Jun 2006
Posts: 1010
Location: Netherlands

PostPosted: Tue Oct 27, 2009 6:32 pm    Post subject: Tutorial: Welding a cylinder to a plane Reply with quote

Hey guys

I often want to attach a cylinder to a plane. This can be cumbersome because alot of vertices are involved. Now, I've found a nice workflow to weld a cylinder with a random number of segments to a plane:

1. Make a cylinder and an object you want to weld it to (I made a cube in this case, but it can be anything with a big polygon to put the cylinder through).



Make sure to remove the cylinder cap that sticks inside the cube. We don't need it!

2. Select the polygon of the cube that intersects with the cylinder. This must be one single polygon. Use the extract tool to turn that polygon into a single object. Make sure that "remove original polygons" is checked.

Select all the polygons of the cylinder that intersect with the cube and turn them into one object by using the same method.

3. Now, select the two objects that we just made (the parts of the intersection) and use the Unite CSG command. It should look like this:



4. Notice that the isolated polygon of the cube is now split into a number of small polygons. Select them and do extract again (use remove original polygons). Then use optimize to make the mesh look nicer.

5. You can now merge all objects together (There should be 4 of them).
The merge operation automaticly welds the vertices together, provided you have not moved any of the objects while doing this tutorial.
The result should look like this:



Hope you find this mini-tutorial usefull. Smile

Cheers

Chronozphere
Back to top
View user's profile Send private message
paul_nicholls
DeleD PRO user


Joined: 05 Dec 2007
Posts: 356
Location: Hobart, Tasmania, Australia

PostPosted: Wed Oct 28, 2009 9:32 pm    Post subject: Reply with quote

Hey, neat!

It works, even with LITE Wink

Thanks for sharing Smile

cheers,
Paul
_________________
Long live DeleD!

Hi ho...hi ho...it's off 3d modeling I go...
Back to top
View user's profile Send private message
AWM Mars
Member


Joined: 06 Jan 2010
Posts: 1195
Location: Wilts England

PostPosted: Wed Feb 24, 2010 4:39 pm    Post subject: Reply with quote

This looks splendid.

I am a bit confused, when I use the unite operation, I end up with more polygons, edges and vertices then I started with, even when I use Optimise.

Using the method you describe above, what are the Polygon, Edge and Vertice counts, before and after?
_________________
Politeness is priceless when received, cost nothing to own or give, yet some cannot afford.

Checkout:
http://www.awm.mars.yourinside.com/
http://www.bccservices.co.uk
http://www.localtradecheck.co.uk
Back to top
View user's profile Send private message Visit poster's website
Jeroen
Site Admin


Joined: 07 Aug 2004
Posts: 5332
Location: The Netherlands

PostPosted: Wed Feb 24, 2010 5:29 pm    Post subject: Reply with quote

I'm probably not seeing it, but I'm a bit confused. If you want to attach a cylinder to a plane, why not only use the Unite CSG tool and use Optimize afterwards? If the cylinder and cube overlap, you get the same results. So why use Extract?

@AWM: you end up with more edges and vertices because the Unite tool (as any CSG tool) creates new polygons. Using Optimize after using CSG is good because, most of the time, it cleans up lots of polygons that are a direct result of CSG.
_________________
Check out Figuro, our online 3D app! More powerful 3D tools for free.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
chronozphere
DeleD PRO user


Joined: 20 Jun 2006
Posts: 1010
Location: Netherlands

PostPosted: Wed Feb 24, 2010 6:53 pm    Post subject: Reply with quote

This is why I don't use CSG directly:




As you can see, a lot of polygons of the big cylinder are split by the CSG operation. Only a few of it's polygons were actually intersecting the small cylinder. I'm not a big fan of DeleD's current CSG because it keeps cutting up your geometry.

Optimize wouldn't be a sollution because it affects your whole object. Let's say you deliberately made a few coplanar adjacent polygons. Those will dissappear as soon as you optimize.

Extracting polygons allows you to keep the rest of your geometry safe from any possible CSG violence. Smile
Back to top
View user's profile Send private message
Jeroen
Site Admin


Joined: 07 Aug 2004
Posts: 5332
Location: The Netherlands

PostPosted: Thu Feb 25, 2010 9:24 am    Post subject: Reply with quote

Your new example is clear - I can see why you would use Extract in certain situations. It makes me think that it would be nice to have an Optimize tool that can operate on selected areas of the object only. Much like Smooth does too. I realize that wouldn't help much in this situation, but it's nice to have.

On a sidenote: it's in the nature of CSG routines in general to cut up geometry if you use BSP trees to perform the CSG action (which DeleD does). Using BSP trees speeds up the computation and provides a relatively clean algorithm compared to some other suggestions I've seen (back in 2005). Although DeleD's implementation isn't 100% full-proof, it can compete with packages like Maya (Elementrix mentioned that a while ago) so it ain't half bad.
_________________
Check out Figuro, our online 3D app! More powerful 3D tools for free.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
chronozphere
DeleD PRO user


Joined: 20 Jun 2006
Posts: 1010
Location: Netherlands

PostPosted: Thu Feb 25, 2010 3:21 pm    Post subject: Reply with quote

Maybe I could change the CSG code to automaticly select the intersected polygons of both objects and operate on only them. However I don't have time in say, the next two months to do this.
Back to top
View user's profile Send private message
Display posts from previous:   
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    DeleD Community Edition Forum Index -> DeleD Tutorials All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum