PDA

View Full Version : How to Off-Set a surface?



MartyC
05-03-2008, 07:27 AM
I would like to know if it is possible to create an offset in Lightwave. This is used as in wall thickness of a plastic part, or, as I want to use it, a structural layer beneath the outside surface. I have done this in Form Z with the offset tool with limited success, and it is used in polyworks by scripting several passes. this is not as simple as changing scale, if the geometry is even moderately complex it will calapse on itself at any complex geometry. Is there a method to do this in Lightwave?

Surrealist.
05-03-2008, 08:29 AM
I think what you are describing could be done well with either a trick using multishift or a plugin called Thickener. You want Thickener 3. (http://www.blochi.com/gfx/thickener_en.html)

The Multishift technique has more steps but better control. You basically copy the shell polygons, flip them, Multifift inwards and then paste and merge points to put the shell back and you'll have your inside faces connected to the outside with a wall thickness.

Hope that is what you needed.

MartyC
05-04-2008, 08:13 AM
very much appreciated, I've downloaded the plugin, I'll let you know about the multishift method

Surrealist.
05-04-2008, 09:42 AM
Good. If you are new to LW you may need a little more info on the Multishift idea. There is a mini tutorial here (http://www.newtek.com/forums/showthread.php?t=63026&highlight=ribbon).

MartyC
05-05-2008, 12:07 PM
The Thickener plugin worked great! I tried the multishift method, but with limited success, maybe because I couldn't find the tool and used smooth shift instead, I am using LW8. is multi shift on version 9? I also checked out your tutorial on modeling, it is very good, I've had LW on my computer for 7 years, but still not that good at modeling, I think I should upgrade. Thanks again

Surrealist.
05-05-2008, 10:48 PM
The Thickener plugin worked great! I tried the multishift method, but with limited success, maybe because I couldn't find the tool and used smooth shift instead, I am using LW8. is multi shift on version 9? I also checked out your tutorial on modeling, it is very good, I've had LW on my computer for 7 years, but still not that good at modeling, I think I should upgrade. Thanks again


Multishift came with 8.5. Glad thickener worked. What you would need is SupperShift not SmoothShift it can do the same thing as Multishift but with less ability to fine tune.

bjornkn
05-06-2008, 02:10 AM
Don't you just love it, getting a new tool with such a meaningful name as SuperShift, instead of making them one tool with new options/settings ;) I'll bet we soon will get a new Super Pro Bandsaw too ;)

BTW, thanks for the tip on Thickener 3. I've been using the v1 for a hwile with good results, but wasn't aware of the upgrade.

Surrealist.
05-06-2008, 03:57 AM
I know what you mean. So many tools so little need for so many that do the same thing or that should be part of one.....

And you are welcome on the tip. :)

Giacomo99
05-11-2008, 01:13 PM
MartyC- FYI, what you're describing is a general class of operations called "shelling," and as far as I know there's no polygon-based modeler that can do it all the time with perfect results. I'm glad Thickener worked for you in this instance, although if you use it a lot you'll probably run into cases where it's not sufficient. Spline-based modelers such as Rhino generally handle shelling better.

Surrealist.
05-11-2008, 10:43 PM
Interesting thing about the Multishift tool for this is it gives you more options in the way the mesh is shifted by choosing different settings there. Secondly you can choose the direction of the shift. Thickener 3 says you can do this but I have not had luck with that working on my system. It always goes Outer. Inner and Seam have the same effect as Outer. With Multishift you can go in or out and also you can choose how the shift happens along the normals.

This may or may not be up to par with a spline-based solution, but it is far more options within LW and even still there are some things that Multishift will not work well on. I have found it has a tendency to go haywire on certain meshes.

fyffe
05-15-2008, 02:57 PM
I would like to know if it is possible to create an offset in Lightwave.

I would also suggest my plugin HD PumpIt. It computes a true thickness-based shift, which is not just following the normals. It's also WAY faster than LW's built-in tools, so you can use it on even severely huge models interactively. Multishift grinds to a halt on big models.

Check out the movies:

http://www.happy-digital.com/pumpit.asp

Unfortunately not free, but it's really cheap.