Interactive spin modifier in 2.5 ?

No. Once you exit out of the spin tool you cannot then change it later. You can change its settings at anytime if it was a modifier.

Richard

This would be an awesome tool. Anyone making cylindrical shapes, wine glasses, lamps, wheels etc would benefit immensely. Yes there’s a spin tool, but what if you want to change the profile or your shape? You can’t, at least not easily.

Might want to call it ‘Lathe’ too. Spin implies motion (But that goes for the tool too).

Lathe modifier sounds pretty good!

Anyone doing that should use curves and bevel objects. More flexibility than a lathe modifier could ever have.

Martin

The trouble with curves though is that you have to use curve tools. Blender’s polygon tools are are nicer, and there are more of them. Additionally, they don’t work with subdivision surfaces, don’t support UV’s, and you can’t really control where the detail goes (it evenly subdivides between the curve points to get the final smooth shape.)

Also, when using bevel objects you actually have to have two curves, one for the round form, and one for the lathing/bevelling. This slows you down. You have to line them up to get a good sense of the size if you want to do stuff with precision.

I clicked once on this little Toggle button… must have done it “out of context” because nothing seamed to happen… I’ll go have a look on it afterwords.
:wink:

Curves have implicit UVs. No stretch, more precision in subdivided areas. (the flag to turn that on isn’t exposed in 2.5 yet though).

The same way subsurf works, except that when you subdivide a curve the added CVs don’t change the shape, it only adds more subdivisions locally.

Anyway, I’m not saying a spin modifier is a bad idea, I’m just saying we already have better tools for that kind of work (revolution profiles).

Martin

I could be wrong, but I think campbell was the one who submitted a patch for a spin/screw modifier, unfortunately yah not before 2.5.

Actually, the modifier code in blender could really use some reorganization, they’re basically all in one huge file right now, which makes it pretty confusing to get up to speed on how to build your own. I believe that too was also actually a submitted as a patch, but again pre 2.5.

Hopefully someone who understands the modifier code can make a tutorial on how to add a really simple one. Maybe that should wait till 2.5 is stable though, and the modifiers are better organized.

Unfortunately, I am not smart enough to do any of the above :’(

not that i am against modifiers, but teeth has a point here.

That’s the point, I think that the request for a spin modifier is not to have a better tool, is to have a tool for different uses. Just thinking to the animation possibilities it makes this modifier a nifty tool to have. Blender has great modelling tools, but the more we get these tools animatable, the more Blender will opens horizons to creative challenges.

Would it not be useful to have certain modifiers, like this, save local coordinates for the 3D cursor, and modify it with that location? Object origin is nice and all, but sometimes you need a different coordinate to modify with, and messing with empties could get really annoying.

Anyone making claims like that should actually try it first :slight_smile:

I’ve made quite a few bottles and glasses and things in my time and although I love curves where they’re appropriate, I’d never even begin to consider using them for this, for all kinds of reasons. They’re just not practical outside any basic function:

  • Yes they have ‘UVs’ but not in a very useful sense, you can’t edit them or lay them out how you like, they’re all constrained to the one 0,1 layout which stretches if the tube is tapered, their inflexible UVs don’t support things like UV projections
  • It’s a pain to actually use - you’ve got two objects instead of one which makes it easy to select the wrong one, get things wrong when duplicating, more difficult to rig and parent. The actual way of working with bevel objects is quite unintuitive (having to keep in mind offsets from object origins etc rather than just modelling what you see). The weird backwards nature of ‘bevel object’ means that the actual geometry is not the curve that defines the profile, but the circle that defines the slice. And at default 0,0,0 rotation the two are at 90 degrees from each other rather than overlapping.
  • Geometry’s way more limited - can’t give the revolved shape thickness, or properly cap the ends. Can’t give them sharp edges. Can’t easily split them up for multiple materials. Deformation tools are pretty much non-existent.

etc…

:slight_smile:

(for the record, I think a lathe modifier would be really really nice)

Now i see the light… why not rearragne the curves and bevel object functions into a brand new modifier? it could then have lathe/spin, linear extrude, or object deformation options to operate on meshes or curves

I agree with Broken, I also found curves not reliable to make precise shapes (they were bottles in my case).

Unless I misunderstood, it’s not true, that you can’t give the revolved shape thickness. If you use a circle as bevel on a circle, you get a donut (and variations thereof).

Other than the two objects thing, all of those points applies equally well to a spin modifier. You wouldn’t be able to give sharp edges (smooth flag is per face), you wouldn’t be able to split it for multiple material (per face again), same for UV. The only thing working slightly better would be deformation tools, since you’d be able to assign vertex groups (there’s still be replicated along the slices, so no moving one side separately from the other).

In both case, beveled curve or spin modifier, you’d have to convert to real mesh to do anything interesting.

Martin

In the case of the mesh modifier, it wouldn’t be a conversion - it’d just be applying the modifier. You’d get exactly what you see. When using a curve, you’d likely have to lower the resolution, then convert to mesh, then apply a subsurf modifier, then have to go in and add the necessary creases and points of get sharp areas.

With the modifier, there wouldn’t be any such extra steps or guesswork. Plus again, the annoying two objects thing.

anyone notice in 2.5 you can convert a mesh to a curve in the Alt+C menu?

Semantics.

You’d have to do the same thing with a spin modifier except being able to add the subsurf modifier earlier.

I guess it’s a matter of workflow preferences. Some people are more used to working with curves, other prefer meshes.

Like I said, I’m not against a lathe modifier at all.

Where’s the guesswork? Guesswork (to me), means it’s either not documented well enough or not clear enough in the UI. So please, explain.

Martin

Theeth: This image shows that there is a difference between a lathed curve and the converted low res mesh with subsurf applied. The deselected mesh is the original curve shape, whereas the selected one is the resulting subsurf mesh.

http://www.reynish.com/files/blender25/curve_to_mesh.png

This is what I mean by guesswork. When converting from curve -> mesh + subsurf modifier you get different results. This wouldn’t be the case with a mesh modifier. It’s WYSIWYG if you will.

I also note that it would also be very useful to have spin as a modifier if you can also spin duplicates of the mesh to be spun with automerging of verticies at the edges like the array modifier does.

This would be incredibly useful for things like ornately patterned collumns or even some glasses and vases with a buttload of jewels modeled onto them, you can change the duplicated section if you change your mind and it would automatically be applied to all the other sections.