Nurbs curves

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Hi,
some noob modeling questions regarding Nurbs curves:

#1 What tools are available? Only what's to find under TAB>NURBS?
That's a mix of surface and curve tools, obviously. Not so well-arranged…

#2 What's the simplest way to edit the curve? Add, delete, cut,…
Some ‘move component tool’ anywhere? No, right?

#3 Are there selection filters for:
'subcurve'
'segment'
'isopoint'
'boundary'
Don't seem to be…

#4 Why do closed curves always display a polygon also? Can I turn this off?

#5 Can I import
AI/EPS
DWG - Not directly, I know. What's the best workaround?

Got 100 more questions, but that's enough for a start.

Thanks!
Best regards,
Eugen
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Ad #2
Found out that you need to be in ‘Show Handle’ tool to be able to move or add points. Better than nothing.

The hotkey for ‘Show Handle’ is ‘Enter’ - I'd like to redefine that, but the Hotkey Manager seems not to list that command when I search for ‘Enter’… bug?


Something I notice:
It's very easy to get completely swamped in some ‘mode-hell’ when switching tools… horrible! Hard to explain, but suddenly I'm not able to edit that curve anymore with the Handle tool…

This whole viewport interaction business needs some serious cleanup… I believe there has been a lot of discussion already, and I can only confirm that.

Why do I need to switch to Camera tool to be able to switch view, for example?

Got sidetracked, sorry. The topic was Nurbs curves…

Thanks!
Eugen
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Tupaia
Why do I need to switch to Camera tool to be able to switch view, for example?

Does Space-1/2/3/ etc work without switching to Camera tool?
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#1- one advantage that I have found in houdini is that it is very easy to switch back and forth in between different geometry types due to its procedural nature. I think depending on what you want to do, there may be a way to do it even outside of the NURBS context

#2 - in addition to be able to enter the curve tool state, you can also add additional operators to do modifications outside of the creation context. For example, the edit SOP or transform SOP would allow you to move points outside of the curve edit SOP (and generally their functionality is more geared towards editing to where you can modify multiple points, use brush tools, do soft mods, etc.)

The reason you may not be able to re-enter your curve node state could be that you do not have the curve node selected in your network view. Try selecting the curve node and press enter (this is similar to how in SI, you can select modifiers in the explorer and modify their parameters)

#3 - I have not played too much with these particular component types in houdini, but the group node is a way to generate selection sets procedurally which can then be used on other operations (i.e. you can use it to procedurally select boundary edges, every primitive that has 3 vertices, any edges that are within a particular edge length range, normal angle, whether an element is inside a volume, etc.) There are also operators that you can use to classify your geometry via attributes based on information such as curvature, position, etc, which you can use to modulate operations (i.e. ray points to the closest surface by their curvature). These are similar to attribute maps in SI

#4 Check the display options (press D in the viewport). I know in there there is an option to keep closed curves unshaded i.e. without a polygon

#5 - yes to AI/EPS. The file node should be able to do it. You can even make your own importers using a python SOP (which I have used to make an SVG importer). I have not tried DWG, but is the format ascii or in any form or way parseable via python?

Hope this helps!
-G
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Thanks, guys!
Have to try things out and learn…

Anyway, in the meantime, I watched
https://vimeo.com/40771484 [vimeo.com]
and in fact there seem to be the most wanted curve tools in place, but the whole workflow feels convoluted and fiddly.
The price for flexibility? Nah, this should become simper, and I'm sure it can.


ad #4
There's
Display Options > Geometry > Shade open curves
… but I can't find something like ‘shade closed curves’.


ad #5
DWG is the native AutoCAD file format. It's binary, and I think you need a dev license from Autodesk to get access to the parsing library. That's something SideFX must be willing to do. F.e. 3ds max or Cinema4D natively support it.

EPS import is there, true, but it simply does not work, or is very unreliable. When you try something newer than ‘Illustrator 3’, Houdini locks up. That's poor.
Does it make sense to log a bug for this?
Data exchange is very important, and Houdini is somewhat exotic anyway. Hope this will improve.

Cheers,
Eugen
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but the whole workflow feels convoluted and fiddly.
The price for flexibility? Nah, this should become simper, and I'm sure it can.


It appears that Houdini is quite modal.

http://en.wikipedia.org/wiki/Mode_%28computer_interface%29 [en.wikipedia.org]

Once you learn it it's simple but you have to learn it.

Tupaia
EPS import is there, true, but it simply does not work, or is very unreliable. When you try something newer than ‘Illustrator 3’, Houdini locks up. That's poor.

Make sure the AI file is uncompressed.
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Regarding modality: obviously Houdini is.
Softimage isn't, really. That, among many other things, make it such a joy to use.

No disrespect meant, but as a user, I couldn't care less what paradigm the developers chose, and for what reason. I just care for ‘complexity made simple’ and the least possible number of mouse clicks.
Isn't this one of the main topics around the SI-Users forum here?


EPS: cool, it works when compression is turned off! Thanks!
The docs (which I could have consulted first… ;p ) state that open curves are unsupported - that's not true anymore. I just managed to export open and closed curves from AI, CS6, compression off (the ‘create PDF compatible file’ checkbox has no effect).
Text, however, has still to be converted to paths.

Best regards,
Eugen
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I would have to say that what I found about houdini is that you do a lot of mouse clicks upfront, but then you do barely any once your system is in place The program's paradigm thus far has been to build networks on which some data flows in and new data comes out. In that regards the program has been very successfull, as we have experienced at my studio

We actually use it in combination with other software such as zbrush, maya, etc and have found that you get the best bang for the buck by mix and matching their functionality. However it is quickly becoming more and more our software of choice for making assets that are very strongly “typed” (a good example is a system we have to build 3d logos out of SVGs. Although you can model them manually quickly quickly in C4D, the system we built in houdini allows you do sweeping changes to all of our logo models within minutes and very few clicks)

I think a good example of the program strength can be appreciated on Kim Goossens road generation video. I would argue that this takes the least clicks than any other program to model a road and it uses the exact same interface you used for modifying your curve:

https://www.youtube.com/watch?v=jOLhnwllpgs [youtube.com]

That said though, you are right about your note on what this forum is about giving a fresh breath to some of the interactive aspects of houdini, and as a softimage user, I could not imagine a better software to look at for it.
-G
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