Go Back   Foundation 3D Forums > Techniques, Instruction > 3D
FAQ Members List Calendar Mark Forums Read

3D Tutorials and your questions on your particular 3D application. Or post questions for general 3D help.

Reply
 
Thread Tools Display Modes
Old 20th Feb 2016, 09:40 AM   #1
Starbase1
Registered Member
 
Starbase1's Avatar
 Gallery
Blender LightWave Modo Poser Terragen Vue Gimp Paint Shop Pro Photoshop
 
Join Date: Dec 2007
Location: London
Posts: 12,724
Default Index - Cutting curves into curves

I've generally bidged this, but thought it worth seeing if anyone could tell me the best or correct way to do it...

The problem I have is with smoothing when I have to cut into one curve with another, often when I want to cut a recess into a curved section of rocket hull.

I attach two images, one of the typical rocket geometry, and another of the kind of feature I want - note the two recessed areas near toe top of the rocket photo.

Here's the kind of thing I would do now.

1. Make a disk a tiny bit bigger than the recess I want to cut, stencil in an outline.
2. Shrink the disk a bit and stencil in the recessed part. This should restruct a smoothing mess to the narrow ring around the cut.
3. Then I can start to build the stuff in the hollow.

Now it generally dosn't show problems at visible level, (particularly if I can avoid any specular or reflection on the surface), but cleary the rectangles that form the hull are now n-gons. Not good.

So what's the best way?

Nick
Attached Thumbnails
Click image for larger version

Name:	DCP_3086.JPG
Views:	144
Size:	132.8 KB
ID:	81178  Click image for larger version

Name:	wires-1.jpg
Views:	147
Size:	193.8 KB
ID:	81179  
__________________
- - - - - -
My web site: http://nick-stevens.com/
Me on twitter, @runnymonkey, https://twitter.com/runnymonkey

Starbase1 is offline   Reply With Quote
Old 20th Feb 2016, 08:56 PM   #2
JackN
Moderator
 
JackN's Avatar
 Gallery
LightWave Illustrator Photoshop After Effects Premiere
 
Join Date: Dec 2007
Location: Sparta, TN
Posts: 3,709
Default

Quote:
Originally Posted by Starbase1 View Post
I've generally bidged this, but thought it worth seeing if anyone could tell me the best or correct way to do it...

The problem I have is with smoothing when I have to cut into one curve with another, often when I want to cut a recess into a curved section of rocket hull.

I attach two images, one of the typical rocket geometry, and another of the kind of feature I want - note the two recessed areas near toe top of the rocket photo.

Here's the kind of thing I would do now.

1. Make a disk a tiny bit bigger than the recess I want to cut, stencil in an outline.
2. Shrink the disk a bit and stencil in the recessed part. This should restruct a smoothing mess to the narrow ring around the cut.
3. Then I can start to build the stuff in the hollow.

Now it generally dosn't show problems at visible level, (particularly if I can avoid any specular or reflection on the surface), but cleary the rectangles that form the hull are now n-gons. Not good.

So what's the best way?

Nick
I think I understand what you are asking...

Not sure if it's the best way, but in a situation like that, I'd make a disk of the correct size and stencil, then smooth shift that in instead of the size reduction from larger than needed.

Then the next stencil and smooth shift.

Give it a try that way with something easy before you do it on the rocket and see what you think about the results.

If you have any issue with smoothing between angles because they are the same surface, you can cut and paste the piece(s) that are set inward and it will produce a new set of points at the border and fix surface smoothing errors. It will still be the same surface but the extra points will help the angle change. Just remember not to merge those particular points later on or you will be back to square one there.

By the way... Booleans will always produce some clutter. Useful to use you Poly Stats and triple non planars, delete 1 and 2 point polys, etc and if you still have higher than quads select the 5 point or higher polys and triple them.

I hear that the next version of LW will have some modeling tools and stuff for once, not sure if they are going to do anything with older tools and fix some of that up though.
__________________
Lightwave 2015
PsychoBabyl.com
My Deviant Page
JackN is offline   Reply With Quote
Old 21st Feb 2016, 05:07 AM   #3
Gordon Robb
Contributing Member
 
Gordon Robb's Avatar
 Gallery
LightWave ZBrush Corel Paint Photoshop After Effects Premiere
 
Join Date: Nov 2007
Location: Scotland
Posts: 7,284
Default

If I understand your reasons for the big and small stencil being to create a control loop before you extrude. I'd do it this way. Just use the biggest stencil. Then select those polices and using smooth shift or multishift make them smaller. This gives you a control loop that has all the pollutes in a better shape. Then just extrude the shape.
__________________
Windows 8 Pro | i7 3770 OC | 32 GB Ram | Nvidia Titan x 2 (one Black) | Octane Lightwave V2
Youtube Channel for Sketches
Gordon Robb is offline   Reply With Quote
Old 21st Feb 2016, 08:22 AM   #4
Starbase1
Registered Member
 
Starbase1's Avatar
 Gallery
Blender LightWave Modo Poser Terragen Vue Gimp Paint Shop Pro Photoshop
 
Join Date: Dec 2007
Location: London
Posts: 12,724
Default

Thanks for the suggestions. Thing is, I really don't see how they will avoid the problems I have with the current method I use...
__________________
- - - - - -
My web site: http://nick-stevens.com/
Me on twitter, @runnymonkey, https://twitter.com/runnymonkey

Starbase1 is offline   Reply With Quote
Old 21st Feb 2016, 10:48 AM   #5
Rigel
Moderator
 
Rigel's Avatar
 Gallery
LightWave Photoshop
 
Join Date: Nov 2007
Location: London (the other one, in Canada)
Posts: 22,567
Default

Cut a hole in the rocket then model the indent as a separate piece. Do NOT weld the points or you will cause smoothing errors.
__________________
Those who say it can't be done,
should stop interrupting those of us who are busy doing it!

------------------------------------------------------------
Other Projects

The Universal Joint
Beechcraft 2000 airplane
LadyBug (Firefly class freighter)
Rigel is offline   Reply With Quote
Old 21st Feb 2016, 11:17 AM   #6
Starbase1
Registered Member
 
Starbase1's Avatar
 Gallery
Blender LightWave Modo Poser Terragen Vue Gimp Paint Shop Pro Photoshop
 
Join Date: Dec 2007
Location: London
Posts: 12,724
Default

Quote:
Originally Posted by Rigel View Post
Cut a hole in the rocket then model the indent as a separate piece. Do NOT weld the points or you will cause smoothing errors.
You still end up with bgons that are differently connected to neighbouring geometry. (though what you suggest helps).
__________________
- - - - - -
My web site: http://nick-stevens.com/
Me on twitter, @runnymonkey, https://twitter.com/runnymonkey

Starbase1 is offline   Reply With Quote
Old 21st Feb 2016, 11:50 AM   #7
DaveK
Registered Member
 
DaveK's Avatar
 Gallery
LightWave Poser Photoshop Premiere
 
Join Date: Dec 2007
Posts: 741
Default

I've used the plugin JettoBevel successfully after cutting a stencil.
__________________
On the plus side, selfie sticks make great lightning rods.
DaveK is offline   Reply With Quote
Old 21st Feb 2016, 11:56 AM   #8
Omnipotent
Registered Member
 
Omnipotent's Avatar
 Gallery
LightWave Modo Vue ZBrush Photoshop After Effects
 
Join Date: Oct 2010
Location: Sweden
Posts: 1,839
Default

wait what exactly do you want to do? cut out the peroxide fill bit? and also the angled cut just below it?
__________________
"Do onto others before they do onto you"
Omnipotent is offline   Reply With Quote
Old 21st Feb 2016, 12:16 PM   #9
Gordon Robb
Contributing Member
 
Gordon Robb's Avatar
 Gallery
LightWave ZBrush Corel Paint Photoshop After Effects Premiere
 
Join Date: Nov 2007
Location: Scotland
Posts: 7,284
Default

Quote:
Originally Posted by Starbase1 View Post
You still end up with bgons that are differently connected to neighbouring geometry. (though what you suggest helps).
Could you make the cur in the fuselage blocky? I'd without ngons and have the modelled bit cover that up?
__________________
Windows 8 Pro | i7 3770 OC | 32 GB Ram | Nvidia Titan x 2 (one Black) | Octane Lightwave V2
Youtube Channel for Sketches
Gordon Robb is offline   Reply With Quote

Go Back   Foundation 3D Forums > Techniques, Instruction > 3D
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 08:26 PM.


2006 - 2013 Foundation 3D