What is really possible with T-Splines.....

[PhilProcarioJr]

So some coworkers keep talking about how limited T-Splines usefulness is. To be honest it's not limitations of T-Splines or Fusion it's the person using them and their knowledge of the tools. I have even seen post here on the boards downing on T-Splines. 

So anyways a friend challenged me to a bet, he claims I can not get the orc head model from Topogun into Fusion 360 as a CAD model fully editable. The head is made up of over a million polygons. Almost 2 million. Here is what the highres model looks like.

The challenge was two fold:

1st part is to model the head using only Fusion 360 and that's what I am going to post today. 

2nd part is I can use whatever tools I have as long as I end up with a fully editable CAD model.

So anyways here is what I came up with after 3 hours in Fusion Sculpt environment using just T-Splines.

Here is a video showing that the T-Spline mesh is fully editable:

I am not happy with this at all but I think it's a good start. More to come....

Cheers

[0502880]

Hi Phil!

Nice work again with T-Splines! I also got good advice from you here in forum how to use quads (and avoid E.V.I.L. triangles...). Needs sometimes a little bit more imagination to find the proper solution. Still I like to ask you, should there come any shape problems there in the (sharp)corners where two quads meet one if you need to modify the top shape?

Then an other question, a little bit philosphical; would you get some advantages to use T-Spline versus straight revolve function in such a rotational body? I understand well, that you have shown to your co-worker that it's possibble to do with T-Spline, but still I like to ask. I'm interested to learn to use T-Splines, because there is certain limitations especially with loft function... For me it's still difficult to handle exact details with it, but your examples shows they are quite possible to do! Some users will warn to use T-Splines and "normal" modelling features (fillets etc.) in same body; what is your experience and advice in that matter?

[PhilProcarioJr]

@0502880

"Still I like to ask you, should there come any shape problems there in the (sharp)corners where two quads meet one if you need to modify the top shape?"

Hmm, that's hard to answer but I feel 99% of the time I would say no there will not be any shape problems. That probably needs some explaining though. The quad section at the top and bottom of the cylinder was separate T-Splines and the edges were welded to the side, so if I needed a different form I could cut that out and replace it with any other form I want. One thing that I don't think most people understand about T-Splines is the rules for combining them are almost the same as the rules for NURBS modeling, but the way you model is like Sub-D. I keep seeing people trying to make finished forms from one T-Spline...as long as the shape is simple this is fine but for complex surfaces you need multiple T-Splines. Once you have these multiple patches of T-Splines you need to understand how to put them together without messing up the overall shape. That's where the NURBS rules come in. Combine this knowledge and you can make anything with T-Splines.

"Then an other question, a little bit philosphical; would you get some advantages to use T-Spline versus straight revolve function in such a rotational body?"

The answer to this depends on your end goal...is the shape going to become something organic or stay a cylinder? Another question to ask yourself is when this becomes a solid or a patch is the surface clean or are there a bunch of faces that are like little slivers that will cause other operations to fail? If I convert this T-Spline (55 Gallon Drum) it gives me a very clean surface. If I revolve it, then it will split it somewhere that is uncontrollable. I prefer to retain complete control over the surface of my models, but that's just me. 

"Some users will warn to use T-Splines and "normal" modelling features (fillets etc.) in same body; what is your experience and advice in that matter?"

Almost all of my work uses all available tools (Solid, surface and T-Splines) unless it's what I call mindless CAD work....I hope this answered your question.

Cheers

[Anonymous]

As long as the pay reflex's the earlier part of what you said, then no worries sticking around 😉

[PhilProcarioJr]

@Anonymous

It doesn't...not even close....

[colin.smith]

I agree with @PhilProcarioJr, when you are approaching a complex sculpt project it is always easier to break the body down in to smaller parts and weld them together.

I'm not as talented as Phil in sculpting, the most complicated sculpt I've done is the Stormtrooper helmet below.  The main body of this is all T-Splines there are decoration items that I did in Solids because it made more sense.

You can see below approximately how many different sections I created when I made it. 

In cases like the ear covers they are not connected to the body of the helment because it doesn't need to be. 

[PhilProcarioJr]

@colin.smith

Can I see your T-Spline control meshes for this helmet?

[colin.smith]

@PhilProcarioJr - that's a little personal don't you think?

More information here:

https://gallery.autodesk.com/fusion360/projects/stormtrooper-anh

Colin

[PhilProcarioJr]

@colin.smith

lol...

Nice work on the stormtrooper helmet by the way, but I have to ask...where is the rest of him? 

[colin.smith]

@PhilProcarioJr, on the moon of Endor somewhere I supose..

[0502880]

Again, thank's for your throughgoing answer! Yes, I have already noticed that more complicated shapes should be done from several faces. But combining those together could be sometimes painfull... Probably the only way is to take care of the same number of vertices. And good nerves 😉

I suppose, that your experience ensures the good surface quality without bumps and other surface problems. Because you can see sometimes extremely nice looking T-Spline models, but if you take a closer look, you can find several faults in surface. That's no problem in "show" products, but if you should do a production ready consumer good, those faults are not allowed.

Do you use a lot those smooth transitions with modify function? As you mentioned in your one post, freeze command isn't always useful... And of course, knowledge and skill ensures quality!

[PhilProcarioJr]

@0502880

" I have already noticed that more complicated shapes should be done from several faces. But combining those together could be sometimes painful... Probably the only way is to take care of the same number of vertices."

Combining them together is actually pretty simple once you know how. As to the second part of your comment about using the same amount of vertices, this is actually not an issue. To explain...what you really need to learn is how to make connection loops in the geometry. Connection loops will lower or raise your vertex count around joining edges. This can be tricky but once you know what works and what doesn't it's pretty straight forward.

"you can see sometimes extremely nice looking T-Spline models, but if you take a closer look, you can find several faults in surface."

This is what the zebra analysis and curvature tools are for. Check your models often.... You can turn on curvature analysis while you work and it will show flaws in your surface in realtime as you move stuff around.

"Do you use a lot those smooth transitions with modify function?"

I'm not sure what you mean by this, can you explain more?

[colin.smith]

@0502880,

An old trick from my Alias modeling days is to use the analysis tools to help me determine the quality of my surfaces.  Zibbra and Curvature Map Ananlysis.

There is a balance between the number of faces and the smoothness of the surface.  T-Splines are curvature continuous by default (except through star points where they are tangent) so a general rule is to have as little data as possible to define the surface to keep it as smooth as possible.  Which is often easier than is sounds.  I spent a lot of time using the Curvature Map Analysis tool and tweaking verts in order to get some uniformity.  You can make yourself mad doing this but it is worth it in the final result.

[0502880]

"Do you use a lot those smooth transitions with modify function?"

"I'm not sure what you mean by this, can you explain more?"

Sorry, I didn't use right terms... I ment Soft Modification function under Edit form menu.

[PhilProcarioJr]

@0502880

"I ment Soft Modification function under Edit form menu."

I use that a lot but not all the time, it really just depends on the results I am after.

I hope to have some training videos after my vacation is over. Right now I'm trying to get over a nasty flu.

[PhilProcarioJr]

[PhilProcarioJr]

Off and on I have seen people ask how to make a domed wire mesh, so I decided to take a stab at it with T-Splines...surprise.....Here is my 15 min try at it...

[Anonymous]

Absolutely stunning! ****. I dont think I can contribute much more than that.

[PhilProcarioJr]

82 T-Splines and one solid....

[O.Tan]

Phil, you're embarrassing all of us! hahaha.

Keep up the good work!

[0502880]

Hi Phil,

again 100% work! Could you open a little bit, what was the key method to get that kind shape? Did you use sketch + pipe method or something else? Suppose, that you have had some sphere shape as a quide element?