Modelling Questions: Subsurf, Particles, Armatures

The interface, modeling, 3d editing tools, import/export, feature requests, etc

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philovivero
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Joined: Tue Jul 06, 2004 10:57 pm

Modelling Questions: Subsurf, Particles, Armatures

Post by philovivero »

First, to entice you, here are the renders I've been doing lately. Note that most of the renders you see you can replace the ".jpg" with ".blend.gz" to get the .blend.

http://faemalia.net/Blender <-- Warning. Not work-safe!

Now, on to the questions:

1. Can particles follow an armature? I want this to add hair to my model, and I want to control where the hair flows. I want to use particles as hair.

2. When you set, in mesh edit mode, that moving a particular vertex moves others as well (O key), can you set a sphere of influence so that it only pulls say the vertexes immediately attached, or the next level out, etc? This would be ultra-handy in modelling.

3. Can you, when using subdivision surfaces, when subdividing the control mesh, or using the knife tool, or face loop cut, somehow preserve the shape of the subdivision surface more closely? It always screws up my subsurf shape when I use any of these tools.

4. Can you define in a single mesh that a set of vertexes X and a set of vertexes Y should have symmetry? I know you can create a half-mesh, duplicate it linked, then get some symmetry that way, but the amount of work involved stitching two meshes back together is prohibitive. (Look at my model. Image stitching the two halves together).

5. When I add a bone into my armature and then in pose mode put in a rotation copy constraint, the bone will deform before I've rotated the parent bone at all, adding strange lumps into my deformed mesh. How do I tell it "this position you're in now is the neutral position?"

6. Is there a way, after rigging and posing my mesh, to edit the mesh in the posed shape? Think joint deforms. When the joint is in a neutral position, it looks good, but once I bend it maybe 100 degrees, it looks horrible. I want to fix it in that bent position so that it'll look good in both the neutral and bent positions. It's very hard once the joint is back in neutral position to see what vertexes need to be pulled how.

6a. Are there morph targets? When I bend the joint to its extreme position, often an organic solid is deformed in a very complex way. It'd be nice to model the joint in the neutral position, then in the extreme bent position, then have Blender morph from one vertex mapping to the other vertex mapping depending on how far the joint is bent.

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philovivero

SirDude
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Post by SirDude »

For #2 after you hit o and say g to move a vert(s) you can use numpad+ numpad- to change the area of effect.

slikdigit
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Location: Northampton, MA (US)

Post by slikdigit »

1- they can, at least in the latest release.
2- plus minus numpad, or the mouse wheel
3- hmmmm, a "toughie" but maybe some-one will code this- for now try smoothing and tweaking your new verts.
4- There is a mirror python script somewhere that will give you this functionality. stiching mirrored meshes is not hard if you plan right / start working that way. The reason it was hard for you was because you didn't start out like that. next time alt-d, mirror and model , keep your center vertices aligned (you can even assign them to a group for easy selection, or use non-manifold) when you're done, join the meshes, select the centers and rem doubles with perfect precision. It'll work great, no time lost. I played with your mesh and it was a serious mess, symetry wise. nothing I've ever done in blender has given me such a hard time- and I've made some complex characters.
5- having offsets for rotation / location constraints is a good idea. for now, the bones have to be lined up for no "jump". to make offsets, use parenting and apply the constraint to the aligned parent. the offset child will not "jump"
6- yes , this is a very good request (I should know, I've made it ;) )
6a- yes, these are RVK's . look them up in the docs. (R V K = Relative Vertex Key) there are also absolute keys, for straight ahead mesh animating.

matt_e
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Post by matt_e »

For 3. You can do this easily with the face loop cut - press S to turn on 'Smoothing' before you click finally to confirm. This info is displayed in the 3D View header when using the loop cut tool.

I think you guys also missed what he was saying about the proportional edit. He wants the influence to propagate along the contour of the mesh, rather than based on distance. To take an example, with such a feature you could grab a finger in a closed fist and move it around with proportional editing, without disturbing the fingers next to it. I agree this would be an incredibly useful upgrade to proportional editing.

slikdigit
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Location: Northampton, MA (US)

Post by slikdigit »

yeah, I'm not sure that's what he wants specifically- he may not know about adjusting the falloff, but that does sound like a good idea (the way you describe it)

philovivero
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Joined: Tue Jul 06, 2004 10:57 pm

Thanks for answers!

Post by philovivero »

1. About particles following armatures... are you entirely sure of that? I can make it rotate about the Z axis of the armature, but it only pays attention to the parent-most bone. All bends in the armature seem ignored.

2. Actually, I was thinking the simplest method of adjusting falloff, and the answer given makes me very happy! Certainly falloff based on underlying geometry would also be useful. But I can't think how I'd code such a thing, and I never ask for features or assume a feature exists unless I can think how I might code such a thing myself.

6a. Okay, RVK's might be what I'm thinking of, but I have two misunderstandings about them:

Misunderstanding1: How can I tie the RVK key frames to armature rotations? The more I rotate armature bone for upper arm, the more I want to deform the shoulder vertexes in a certain way.

Misunderstanding2: RVKs seem really one-dimensional. If I have vertexes aligned like A when upper arm is fully rotated in direction X, and aligned like B when upper arm is fully rotated in direction Y, then when upper arm is rotated halfway between X and Y, I'd like vertexes to be aligned halfway between A and B. Yes? Is that possible?

Now what I'm hoping for is a way to parent only one end of an armature bone to another bone, so that when I rotate/move the parent bone, only one end of the child bone moves along. That would be ultra handy for tendons and things like that. Right now I'm stumped with her leg. I can't figure out how to deform it more than only about 45-50 degrees in any direction before it starts looking bad.

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philovivero

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