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Rob_T

Having a little problem with circles.

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So I'm trying to model this:

 

http://www.casrem.com/zoom_e.asp?immago=testata_s_gr

 

And I've run into my old enemy... the circles/ridges.

 

I have to do a few of these things and I've done some similar stuff in the past and I always end up fighting with the ugly dark ridge that shows up.

 

Obviously I'm not a great modeler. But circles have always frustrated me for this reason and I feel I'm must be doing something fundamentally wrong here. In the past I've just pulled everything into Photoshop and "fixed" it. But I'm hoping maybe someone can tell me where I'm falling down here so I can kick this problem once and for all.

 

As you can see the model is already "out of shape." Really makes me wish there were some basic shape building tools in A:M like there is in Photoshop. You know, make a square... make a circle.

 

Anyway...

 

Any help would be appreciated. I am however thrashed and done for the night. I have to be up for class in 4 hours so I'm going to try and get some rest. I won't be back at this until tomorrow night. Just a couple weeks until me 3D classes actually start.

chuck_base0.jpg

chuck1.mdl

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Hi Rob,

 

I suppose there might be two primary approaches to consider here: Modeling circles and Modifying circles.

 

In the first case of Modeling it helps to us A:M to create the circles because A:M will almost always create a better spline layout than we can on our own.

In the case of creating your shape it might be optimum to create a cross-section with extra Control Points (CPs), lathe that into a cylinder or torus shape and then keep only those parts of the shape you need to move forward.

 

In the second case of Modification it'll help to understand how Bias settings help to peak and smooth splines as they pass through Control Points.

For instance, selecting a spline and adjusting its Bias properties from say... 100% to 167% can produce a nicely rounded curve whereas the 100% setting will produce a sharper angle which smooths out only nearer the control point.

 

Note also that if you Right Click in a Modeling window and open your Wizards there should be a Primitives plugin that will build some of these shapes automatically for you. Of course, just because the plugin creates a bunch of splines that does mean you have to keep them all. For what it's worth, I usually prefer modeling my own primitives over use of the Primitives plugin because that gives me fuller control on the end results.

 

In looking at your model I see that adjusting the in and out Magnatude would solve much of your curvature problems (I'm liking 133% a lot).

 

The main issue with the model however will be how the holes in the shape connect to the Control Points around the outer edge/cylinder. The presence of multiple splines all going through the same control point creates an illegal patch which will produce the artifacts (the dark rim you mention) at those locations. The most common solution to get around those problem areas might be to use 5 Point patches after extending that area one step further inward so that the inner spline and the holes don't share those same CP nodes.

 

Depending on your goal, the use of Boolean Cutters to place/cut the holes into a solid cylinder would also work.

For what it's worth... the Basic Steps:

- Lathe your main cylinder and close the top/bottom (If you Lathe with 5 cross sections you can select and close the top and bottom with the 5 point patch tool).

- Lathe your holes (they could be copies of your main cylinder assigned to a different bone)

- Assign the splines/CPs to at least two bones.

- Set the bone assigned to the holes as a Boolean cutter.

- Note the results when the shape is rendered.

The two things that most people have problems with when using Boolean cutters is enclosing the shapes (Boolean Cutters always work better when the shapes are enclosed) and understanding Specified Booleans; where we can tell A:M what to cut and texture based on the hierarchy of bones.

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Hey Rob,

 

I modeled it for you. See Attached. Might not be the best approach, but I hope that will work for you or give you a start. I put a few extra spline rings on the top in case you need it to have more beveling.

 

Cheers,

William

 

chuck2.mdl

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Here's my entry in the topology derby...

 

charlie.JPG

 

 

I...

 

-lathed out the top half of a disk with 12 sections

-lathed out a 4-section "hole" separately

-spliced that hole into a 1/6 section of the disc

-Copied that 1/6 section with the hole in it, then deleted everything

-pasted the copied section back

-deleted a radial spline on one side of the section, leaving just pigtail CPs hanging

-used the Dup wizard to make six copies of the section at 60° intervals around the center

-connected the hanging pigtails back to their new neighbors

-filled in all the empty 5-pointers.

-used CFA to create the bottom half of the disk

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Thanks so much to all three of you. You know Rodney and Robcat... you two are literally two of the top five reasons to own Animation: Master.

 

Seriously. You guys are amazing. Rodney.... get an Amazon Wish List. Robcat. I'll be revisiting yours shortly.

 

Lastly but not leastly detbear, I don't know you well but thank you so much for your help. I love this community. You guys really are the best.

 

EDIT: Rodney I've been using the Font Wizard forever. I can't believe I never noticed the primitives wizard.

 

Herp. Derp

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I guess I spoke too soon. Looks like I don't have a primitives wizard. Explains why I never saw it at least.

 

Ha ha.

 

Yeah I'm still using 15J

 

Oh well. I guess I need to upgrade.

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I guess I spoke too soon. Looks like I don't have a primitives wizard. Explains why I never saw it at least.

 

Ha ha.

 

Yeah I'm still using 15J

 

You can get the v15 version here

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Thanks Robcat. I grabbed it. it didn't have rounded rectangles like I hoped but it's still a great tool.

 

So here's my next challenge.

 

I'm modeling (or trying to) the part circled in red and I'm having some trouble with the rounded rectangles. I'm not looking for someone to do the work for me (although again thank you for the other stuff guys it helped tremendously). As you can see there are three holes in the outer shell. I've included my project file and model files separately so you can see where I'm at.

 

Thanks fir any suggestions. I learn a lot from looking at your work.

 

Rob

disassembled.jpg

chuck2_base_complete.mdl

chuck2_outer_shell.mdl

chuck2.prj

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Don't forget that you can create paths in Illustrator and import them with the AI Wizard. I do that for nearly all my rounded rectangles.

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As you can see there are three holes in the outer shell.

 

My first inclination would be to lathe the shell and use Booleans to make the holes. Those will only show in final renders, but would that not be good enough?

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Hey Rob,

 

I think Robcat has a great suggestion there with the Boulean approach. I normally avoid Bouleans if I can because of the render times, but that doesn't look like it will be hindered much in your case. Another thing to consider in that respect is whether you're going to have to export the geometry into any other APP. If not, it will make things much easier. But if your final destination is somewhere other tham A:M, make sure what you do in A:M will work elsewhere.

 

Looks like a great project. Nice work.

 

I agree...... Robcat and Rodney, as well as others help to make A:M a great experience.

 

William

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Just to try it and say "it can be done"... i can report that this sort of thing can be done.

 

These things mostly depend on good strategy in A:M. I made my lathe outline so it would give splines in convenient places for splicing in a hole later.

 

I only needed to splice in one hole. Once I got that one, I copied that one third of the shell with the duplicator wizard and attached the copies together

Shell06.prj

 

ShellWithHoles.JPG

 

 

 

 

 

 

 

This took me about 90 minutes, which is probably longer than a person proficient with a polygon modeler would need.

 

But I have had the experience in the past of setting up a Boolean punch in a polygon program, waiting 30 or so minutes for it do what it does, only to come back with a "Can't complete Boolean operation" error.

 

So between needing two or three tries in the polygon modeler and one in A:M, maybe I'm not that far behind. :D

 

 

This sort of form is a rare need in character animation, but if you need such an item in your A:M universe, it can be done without heavy lifting.

 

If there is great desire I can do a screencam tut on this, but for most purposes, A:M's render Booleans will serve well and be quicker to model.

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Largent. Thanks man. That's a great tip. Is that the wizard labeled "AI" Is that how you import the AI files? Is there a tutorial anywhere for that?

 

Robcat and Detbear.. Ok without sounding like Bill Cosby and his famous "Noah" set.

 

What's a Boolean?

 

The only Boolean I know is in search engines.

 

I do need to make those little rounded rectangle pads that go inside the holes when the entire unit is assembled so if Booleans are just decals or something that won't really worked.

 

But I suspect that Booleans are something better than that. Is there a tutorial on using them anywhere? I don't recall any mention of Booleans when I did the Tao oh so long ago.

 

Lastly thanks again guys. You rock. Robcat I can't believe you spend 90 minutes on my work. You really are incredibly generous.

 

I know you said something like this is a rare need in character animation but in my graphic design freelance work what I'm coming across more and more is product modeling like this. It's what makes me want to get better at it as more and more of my clients are looking for it.

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A Boolean in A:M is a mesh that will cut a hole in another mesh.

 

They must both have their own bone. The bone for the "cutter" should be a child of the bone for the mesh that will be cut and it must have "Boolean Cutter" ON.

 

Both must be fairly closed shapes.

 

It makes cuts and holes possible that would be ghastly horrors to try to do with splines.

 

BUT... the cut only shows in Final renders.

 

Boolean_Example.prj

 

BooleanExample.JPG

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A Boolean in A:M is a mesh that will cut a hole in another mesh.

 

They must both have their own bone. The bone for the "cutter" should be a child of the bone for the mesh that will be cut and it must have "Boolean Cutter" ON.

 

Both must be fairly closed shapes.

 

It makes cuts and holes possible that would be ghastly horrors to try to do with splines.

 

BUT... the cut only shows in Final renders.

 

Boolean_Example.prj

 

BooleanExample.JPG

Mind = Blown.

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Yeah I would definitely like to know how tie AI plug in works. Just tried it a couple times and got nowhere.

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I know you have to save in an old ai format. version 8?

 

I think it also needs to be a not filled shape?

 

I've only used it rarely.

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I know you have to save in an old ai format. version 8?

 

I think it also needs to be a not filled shape?

 

I've only used it rarely.

 

 

No, it can be a filled shape... sometimes it's good to fill it because then you can see if your 'holes' are open... such as in the letters A, O, P, B, D, Q, R,

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Yeah, just save it as an AI file and make sure to make it ai 8.

 

Make sure the "Auto" radio button is on in the plug-in when you're bringing it in. I have found the plug-in to be buggy, so make sure you save before using it.

 

Keep in mind that sometimes it's smart to think A:M instead of AI when you are making your paths so that they'll be easier to patch when you get them in. Watch for problems. Sometimes when AI makes a rounded rectangle, it doubles up points, which can cause unexpected results in A:M.

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...As you can see the model is already "out of shape." Really makes me wish there were some basic shape building tools in A:M like there is in Photoshop. You know, make a square... make a circle.

 

Always use Lathing to make anything circular. It automatically adjusts the bias of every CP to make the circle round.

 

Lathe out a few things with different lathe settings and click on a CP and look at its bias properties to see how the bias has been changed from the default 100%

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Here's a practical example of the Boolean cutter. I used a Boolean to cut the main porthole on the front of my spacepod model that has a very detailed tooth to the inside surface.

 

Spacepod.JPG

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It is not only AI8 but it is necessary to ungroup everything before you save to AI8.

But with that it should be working very well.

 

See you

*Fuchur*

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This is very usfull for me to use.I would be lost without all this help . Thanks Again

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