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vonpietro
10-08-2018, 04:22 PM
So i have a blueprint of the nautilus, very good.

How would i go about creating accurately the shapes.

It looks like i simply outline each rib and then skin it all.

heres my problem, skinning in lightwave never has worked right for me. theres some ******** about the order of the points or something becuase the wrong points get joined to the wrong points on the next rib giving it instead of asmooth mesh, and unusable wrongly patched mesh.

anyone know the rules for skinning? or is there a better way to do this.

if i have to i will literally select 4 points and polygon it - but thats super tedious and there has to be a better way .

COME on newtek - this is why we need better tools in modeler.
or fix the onld ones so they work propperly.

thanks


heres an example - sorry only FB version here -
https://www.facebook.com/345392525548878/videos/1988121221247749/

he builds a prop from a cad drawing - using something he is calling bridging -

thats what i want to do in lightwave - CAN I?

jwiede
10-08-2018, 05:49 PM
By skinning, do you mean building using NURBS/b-spline surfaces (built out of multi-curve-edged panels), or something else?

Lewis had some excellent tutorials on using native bspline surfaces in LW, though, maybe look into that method? If it's much more complicated than that, might want to look into EasySpline or perhaps even FormZ/Rhino.

vonpietro
10-08-2018, 06:14 PM
i always found splines hard to work with thanks to having point ordering.

So i'm looking for a non slpline method -

basically create ribs and then patch them together kind of thing.

Its like building an aircfraft - you have the ribs of the frame, and you skin it following the contours of the frame.

while splines are probably good for that - they are hard to use. I've had alot of trouble making them skin correctly.

i did find this plugin - going to see if it works - if so it might be what i'm looking for becuase it will do odd sizes between each other and interpolate -
http://www.artssphere.com/plugins/bezierbridge.php

hope it works.

jwiede
10-08-2018, 07:02 PM
BezierBridge is vaguely along the same lines as EasySpline, in that they both focus on allowing easier construction of spline-based surfaces. The point-ordering stuff is generally part of working with spline-based surfaces in LW, AFAICT, so you'll probably not escape it entirely, but maybe with Art's plugin it'll be less of an issue for you. If Art's plugin doesn't help, you should definitely take a look at TrueArt's EasySpline (and there's another free Bezier plugin there too that might help, can't recall name).

All that said, you're reaching the level of work where adding something like FormZ or Rhino might really speed the process. Even FormZ Free might be adequate for your needs, thus might be worth a look. Pkgs like FormZ and Rhino are much more focused around surface-based modeling, and their toolsets make such work much, much easier than attempting to do the same with any poly-focused 3D modeler. Once modeled in them using surfaces, they can even tesselate and export as poly-based model formats for rendering, while keeping the surface-based originals for tweaking and re-exporting.

vonpietro
10-08-2018, 09:12 PM
i'll check it out thanks for the heads up for that. =)

also i found this little interesting thing - a new modeler - they have a demo of it doing wires thats amazing -

newtek take a look - maybe you can get some ideas for modeler from these guys

https://www.rocket3f.com/

jbrookes
10-08-2018, 10:00 PM
So I watched the Blender video you linked.

In LightWave 2015, here's a similar procedure:

- Select Create -> Points
- In the Front or Back view, right-click 8 or 10 points in a circle.
- Select Make Curve -> Make Close Curve
- Ctrl C
- Ctrl V
- T (for Move)
- In the top view, Move the copy along the +Z axis a bit
- Press H (for Stretch)
- In the Back view, stretch the copy a bit to change its shape somewhat
- Press Space to drop the tool
- Make sure you're in Polygon selection mode and select both curves
- Select the Multiply tab and just under Magic Bevel,
- click More -> Create Skin

You can even add a skin to a whole bunch of curves in one go. Just select the entire row of closed curves and choose Create Skin.

Now if you were to do what the guy in the video does and re-shape those curves in Point mode using the Drag tool to match the blueprints that you have, you'd be done in no time.

Rayek
10-09-2018, 01:27 AM
I've always liked the sort-of hybrid approach of B-surfaces in Blender, where splines are use to describe the shape, but the final skinning is polygonal and very controlled. The tool also doesn't care about how many points each spline might have. Also provides some good ideas for new tools in Modeler.

Here's a guy who models a BAE HAWK T1 using B-surfaces:
https://www.youtube.com/watch?v=FHiGH-4L5h4

jbrookes
10-09-2018, 02:34 AM
One thing I should mention about the Create Skin command is that it's finicky, doesn't allow you to change the detail level, and makes odd-looking polygons if you change the shape too drastically from one curve to the next. So if it gives you issues, there's a few more options.

The next one is making a spline cage out of those closed curves. That would involve picking the top point of each closed curve and making an open spline. Then the same for the bottom point of each one. Next, a spline for the left point of each closed curve. And finally connecting the right-most point of each curve and making an open spline as well. Now you'd click on four curves that surround a 'rectangular' space (be sure to connect in sequence.... clockwise for example). Then choose Construct -> Patch. This is very old-skool and is actually how I learned to model in the old Alias PowerAnimator days. Create -> Spline Cage might save you some time using this method.

An easier way, and one that also auto-caps the object's ends is to just use the original closed polygons as a guide in a background layer. Then on top of them, draw a box that's segmented with a few more segments than there are guide curves (see image 1).
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Next, in Points Mode, slide the segments over so that they match up with the curves. The extra segments can hang over the two ends a bit (Figure 2).
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Now you can use the Stretch tool to make each segment's points match up with each curve (Figure 3).
143051

And once that's done, press Tab to check to see if it matches up nicely (Figure 4). If so, go ahead and Freeze it.
143052

You can freeze it a second time if you need more detail.

This gives you quads and is an efficient way to model. The end segments allow you to adjust the cap shapes.

And while in SubD mode, you can tweak the shape to match what you're looking at, using the various deformer tools (like twist, vortex, etc...). In that case, it'll put tris only where needed (Figure 5).
143053

RPSchmidt
10-09-2018, 07:20 AM
You may want to check out this tutorial by Larry Schultz (SplineGod).

https://youtu.be/VOcyliN80sI

The technique he shows when creating the reptile's jaw (creating a single spline, copy, rotate) sounds like it could be very useful when building something like a nautilus.

Using a similar technique, you could create a single spline and copy / rotate / scale each spline around the same axis, then patch as you go.

EDIT: LOL, that's what you get for not actually looking at the reference provided by the OP; totally misunderstood what you were trying to create... Although I think the technique would still work.

prometheus
10-09-2018, 11:46 AM
I would try Cm_Loft...

Spline curves works..end results with polygons,
You can use polyshapes as well.

Choose remove cage if you want to have only polygons without the spline curves remaining, or uncheck it if you still want them there...maybe hit "w" for statistics and choose the curves and paste on background layer if you
would want to change those profile curves.

In fact ..using Cm loft my be faster and better than the skinning method in blender (procedural modeling excluded)
You do not have to select the rail curves, or polyshape profil segments ..just run it and it will bridge all segments.
You can use open curves or closed curves, closed polyshapes...you do have to make sure to understand how to use close spline, mesh or not to get what you want.

Edited..posted a erikals vid to loft to rail, also by Carl merrit, but that is not the one.