ICE Modeling workshop : The Capping Tool

[Guillaume Laforge]

Good evening everyone, here is the first weekly workshop on ICE modeling !

We are going to build a compound to quickly cap a hole in a polygon mesh. I think that it is a good opportunity to learn how to switch between contexts (like from vertex to edges for example).

But not only we will learn something, but it will also give a simple but useful tool for everyday modeling tasks ;).

Here is the scenario :

 

The user will select a vertex somewhere along the hole (so it will be a border vertex) and then a command will apply an ICETree to build a polygon that will fill the hole.

You don't need to focus on the scripting side (the command) but just on the Capping compound.

The compound input will be just an integer (the index of the starting point for the cap polygon) and our output will by an execute port (to set the topology).

The algorithm could look like this :

Store the starting point in a data structure.

Find the next point on the hole and store it too. 

Repeat until the next point equal the starting point.

Use the resulting data with some topology node(s) and cap !

I made a prototype tonight, here is a little demo : http://dl.dropbox.com/u/5533643/Softimage/workshop/ICE_workshop_polycap.rar

That's all for today.

Good luck !

Guillaume

[Fabricio Chamon]

nice one, thanks Guillaume!

here's my attempt. (scene attached).

Am I supposed to post the icetree+description already ?

[Guillaume Laforge]

Damn you are fast !

I forget to say that this workshop is not for people with a name starting by Fabricio, Ciaran, Brad, Eric or Thiago :).

Before sending your ICETree + explanation, you need to clean it a little bit ;).

In my prototype, there is only one custom attribute (the one to store the vertex array) and is more than 100X faster :P

Cheers,

Guillaume

[Eric Thivierge]

Ah man! C'mon! Not all of us Erics can be lumped in with Meister Mootz!

--------------------------------------------
Eric Thivierge
Technical Director
http://www.ethivierge.com

[Guillaume Laforge]

:)

[Fabricio Chamon]

"more than 100X faster"
damn, this makes me a 3dmax and you a Softimage...not fair

ok, hands on again. One question: are you doing it with no
repeat/while nodes at all ? I've managed to build a very rough extrude
along curve compound without the "evil" nodes, but in our case, I
couldn't find a way to search for neighbours border vertices only with
arrays and intrinsic attributes...

[Fabricio Chamon]

...also, are you usgin build array from set ?

[Guillaume Laforge]

You are right, in our case it is not possible to do it without repetition execution are we need to store the next vertex in an array.

I'm using the While node. I'm storing the first vertex index in an array before. The while condition is : Stop if the result is equal to the first element of the array.

Then I'm using the point neighbors of the current vertex. If those points neighbors are border edge, then I pick the first one and push it in the array and repeat.

The resulting array is just the needed, points. Then I needed to find the good order and sort the array with key using its sub-indices (if it was not in the good direction).

My direction test is not always good so once the polygon added, I re-test the first vertex to know if it is still border edge. If yes, I'm inverting the polygon normal.

 

G.

[Guillaume Laforge]

Yes, but only in the part where I try to test if the array is in the good direction. I could avoid it I think.

[Guillaume Laforge]

> I've managed to build a very rough extrude along curve compound without the "evil" nodes, 

You could do a nice workshop with this extrusion without "evil" nodes !

Just an idea ;)

G.

[Eugen Sares]

Guillaume,
thanks for doing this ICE workshop, it's so great to see Softimage getting
enhancements in the modelling department!

Are you planning to "release" all the things that get done here in some
repository, for everyone's benefit?
For the mere "users"...

For another workshop, may I suggest a tool which would really make a lot
of sense having: "Power Extrude".
An Operator that extrudes Curves (with Subcurves) along other Curves (also
with Subcurves), with correct corner mitering.
Know the 3ds max "Sweep" Modifier? This kind of thing.

Extrusions, or their shortcomings in SI, have been discussed many many
times here already. See Kim Aldis' TinyExtrude...
Now with ICE Modelling, time has come to catch up.

Is it theoretically possible, since ICE Modelling does not have NURBS
support yet?
We have the Compounds "Create Extrusion Along Strands", but not "Create
Extrusion Along Curve"...
Yet there's "Create Strand from Curves". Is this the way to go?

I'm thinking about doing it myself, but the learning curve looks a bit
steep at the moment, and a lot of people have a big headstart already.
Let's see...

First step could be an Op that simply creates Tubes = Extrude with only
circular cross section.
In 3ds max, Splines have a checkbox "Renderable" for this. Params are:
number of subdivisions in the cross-section, along the path, and rotation.

What say you?

By the way: my CurveTools Addon is finished. Going to release it after I'm
done with a small Tutorial Video.
Yet Curves alone are not much worth without the option to extrude
them/convert them to polys, that's why I'm asking.

All the best,
Eugen

[Andreas Bystrom]

Getting a bit OT here, but I think a proper greeble tool in softimage is long overdue :P

maybe not the most useful tool but it would make a good workshop too I think

--
Andreas Byström
Lighting TD - Weta Digital

[Fabricio Chamon]

Hi Eugen,

I'm currently in the process of developing an extrude along curve
compound. For now it features:

- number of subd V
- number of subd U (cross sections)
- default circular cross sections if no U shape curve is specified
- V Curve Start Pos.
- V Curve End Pos.
- translate along curve (like on "deform along curve" factory op)
- Cap Top
- Cap Bottom
- Invert Polygons
- Radius
- modulate radius by fcurve profile (along curve)
- Roll
- modulate roll by fcurve profile (along curve)
- Constraint extruded mesh to V Curve

..and this is what I'm aiming to do (or what is still missing):

- subdivision type (Per Span/Absolute)
- Spiral Displace Along Curve (control for radius offset/frequency)
- UV generation/modification

Tomorrow I'm going to post a video + the scene file (which I forgot at
my home pc), so that we can discuss and improve it.

I like the idea o having support for subcurves, will try to implement
it. Also let me know what else features you'd like to see in a tool
like this.

This has been a nice experience to me (regarding ice modeling). So
i'll try to share as much as possible from what I've learned so far.
And about the workshop, I'm all for it!

Fabricio

[Fabricio Chamon]

"Getting a bit OT here, but I think a proper greeble tool in softimage
is long overdue :P

maybe not the most useful tool but it would make a good workshop too I think"

agreed!

[Eugen Sares]

Fabricio, that's brilliant!! Looking very much forward to this!

But pretty please: don't forget the support for multiple Subcurves, for
both path and cross section!
Can't be more than two additional loops for all Subcurves.
It would simplify a lot of modelling situations - you don't have to mess
with 100 separate objects if you keep Curves together in one CurveList.
I'm halfway finished with that tutorial video for my CurveTool addon,
which will be a nice companion to your plugin when it comes to curve based
modelling.

Ah yes: new Revolution tools would also be cool, with Subcurve support...
Just in case you look for another challenge. =}

Best,
Eugen

On Wed, 04 May 2011 17:10:41 +0200, Fabricio Chamon <xsim...@gmail.com>
wrote:

[Guillaume Laforge]

Hi Eugen,

>Is it theoretically possible, since ICE Modelling does not have NURBS support yet?
>We have the Compounds "Create Extrusion Along Strands", but not "Create Extrusion Along Curve"...
>Yet there's "Create Strand from Curves". Is this the way to go?

Yes, it is the way to go currently. Once the curves (without sub-curves...) "converted" to strands, it is easy to do the multi-extrusion using "Create Extrusion along Strands".

To support multi-curves/sub-curve extrusion correctly we would need to add some features. It is not possible to get curves from a group as an array of geometry.

Accessing sub-curves is not always good (I don't remember exactly the detail btw) and getting the curve normal in ICE is not enough to get the correct transformations along the curve. The curve normal from ICE is not wrong but not "rotated" from the beginning of the curve, so you could get some flip along your extrusion.  Of course, you could compute the good normal yourself so it is not impossible at all to get it.

>First step could be an Op that simply creates Tubes = Extrude with only circular cross section.

Take a look at the "Create Extrusion along Strands". There is an extrusion compound inside. It is using a repeat node, but we could avoid it I think.

Cheers

Guillaume

[Fabricio Chamon]

Hi guys, heres a wip (compound attached): http://vimeo.com/23314473

As Guillaume said, the curve normal is not always good, so sometimes
you get a flipped crosssection range. In the compound I'm subtracting
pointpositions from the previous point, then using direction to
rotation to rotate my crosssections *before* positioning then on the
path curve... I think this could avoid the flips, but I'm not 100%
sure.

as far as performance I managed to avoid any repeat/while nodes. Let's
see if I can stay like this till the final version of the compound! =)

talking about subcurves, it's using UV to location to position the
crosssections on the path curve, so it may be possible to switch
between path subcurves already (didn't tested yet). But it would
require a complete revision to contemple all subcurves at once.

As it all started as an exercise, I didn't look at any of the factory
compounds. So please (Guillaume) let me know of any optimization I'm
missing.

[Guillaume Laforge]

Nice work ! And it is really cool to see users starting to build their own modeling tools :)

I didn't take a look at the compound, but will do soon !

Cheers,

Guillaume

[Mirko Jankovic]

nice work!
way out of my CIe reach, no time to tinker there as well as many others I'm sure. :(

But can't wait for a nice compilation like Power ICE Modeling tools.. PIMT !!! (well we can get better name that is for sure :))) You amazing guys make tools the rest of us will think of a name for power modeling toolset :)
cheers

[Sebastian Kowalski]

this is looking really good, and blazin' fast.
i hope i have some time left this week to catch up.
sebastian

[Fabricio Chamon]

...found a way to extrude on all the path subcurves, icetree attached.
Performance-wise it looses a bit because of the "repeat" and the
"merge topo" nodes. But for now it serves as s quick workaround.

modifications:
- exposing the uv to location subcurve index
- instead of setting topology inside the compound it outputs the topology itself

[Guillaume Laforge]

I like ICETree screen shots :), it is a time saver for me !

Avoiding  the Repeat node for the multi-extrusion is possible if each extrusion use the same number of subdivision. Take a look at the "Build MultiExtrusion PackedPolygons" in the "Create Extrusion Along Strands" compound for more info.

But the Repeat node is not a big problem if the number of sub-curves is less than hundred (I think) and it gives the possibility to change the U and V subdiv "per copy" using a custom attribute controlled by the repeat node !

Something to investigate :

Instead of setting the topology for each repeat, try to add the current topo in an array. Then after the repeat, use the Merge Topo Array and set the topology. 

As you don't need to access the new topology between each iteration, it could be a good way to improve the performance (but it will be maybe hidden by the repeat node bottleneck...).

Guillaume

[Christopher Tedin]

You so totally rock! nice work. I'm going to install this right now!

[Szabolcs Matefy]

Amazing...Now I just need to know how to drive this with strands
produced my Melena :)

[Stefan Kubicek]

Bingooooooo!

--
-------------------------------------------
Stefan Kubicek Co-founder
-------------------------------------------
keyvis digital imagery
1050 Vienna Wehrgasse 9 Austria
Phone: +43/699/12614231
--- www.keyvis.at ste...@keyvis.at ---
-- This email and its attachments are
--confidential and for the recipient only--

[Fabricio Chamon]

"Instead of setting the topology for each repeat, try to add the
current topo in an array. Then after the repeat, use the Merge Topo
Array and set the topology"

Indeed. Thanks for the tip.

@Szabolcs: nice idea. It shouldn't be too difficult to use pointcloud
strands as well. Let me see here...

[Guillaume Laforge]

Or use the "Create Extrusion Along Strands" factory compound ;)

-----Original Message-----
From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Fabricio Chamon
Sent: Thursday, May 05, 2011 11:10 AM
To: soft...@listproc.autodesk.com
Subject: Re: "Power Extrude"

[Fabricio Chamon]

lol!!! yes

[Guillaume Laforge]

Here is a screen shot showing the principle for the Cap compound : http://dl.dropbox.com/u/5533643/Softimage/workshop/CapBordersCompound.jpg

As it is a one week workshop, I will send the final compound tomorrow ;). It will be an addon updated at each workshop with the compound(s) and the plugin to apply it. I could add Fabricio Extrude compound also when it will be finished !

Cheers,

Guillaume

[Eugen Sares]

You da man, dude, I tell you!!! ;)

One more thing:
if you did not so already -
on sharp corners on the extrusion path, could you possibly please
compensate the cross section width by a factor so that the outlines stay
parallel to the path (= correct corner mitering) ?
factor = 1 / sin( angle(prevSegment, nextSegment)/2 )
This is a very important feature for geometric/architectural modelling,
believe me!
Been hoping for this for ages now...

Thanks so much!!

On Thu, 05 May 2011 17:26:01 +0200, Fabricio Chamon <xsim...@gmail.com>
wrote:

> lol!!! yes

[Szabolcs Matefy]

I asked it because I need to make geometry hair out of melena, for
example. Unfortunately for some reason melena strands with the ice
compound you mention produce mesh, with each polygon in the center...

[Robert Chapman]

thanks Guillaume,

tried to build this from your screen shot last night, got stuck on
creating 'get last value in vertex array' node figured it might be a
pop from array from the 'cap_vertexarray' but I couldn't seem to get
point location from this without it going red. Also would not know how
to begin to create the 'test double edges' node , but the rest of the
tree , although initially daunting, was fine with constructing from
Fabricio's and yours previous ICE modelling tree examples . there a
whole load of new attributes to learn & pick from now, but Ive not
done much work with arrays yet so its more to do with my rudimentary
logic skills rather than anything wrong with ICE modelling. this is
where the practice is going to help :)

regards,

Rob

[Guillaume Laforge]

If the extrusion is not generated it could be for two reasons.

"Create Extrusion Along Strands" doesn't need some orientation attributes on the point cloud. That's because it does its own calculation to find the good orientation. To do this, it is using the point position and the first strand position as a tangent basis. So maybe Melena system create the first strand position on the point position ? If so, the extrusion will not work. What you could try is doing a remove form array on strand position to remove the first element (as it is not needed in fact). 

Also, if Melena create strands with some non constant number of positions (like 10 strand position on point 0 and 15 on point 1), it could give some trouble.

Just a guess.

Guillaume

[Guillaume Laforge]

Hi Rob, here is the final compound if you want to see the answer :) :  ICE Workshop Addon

You will see that it is not so complicate. In my first test I was trying to get the good vertex array direction to avoid flipped polygons for the cap. It was some rather boring graph dealing with arrays.

Finally, it is easier to create the capping without checking for the good normal orientation and then do the flipping only if the selected vertex is still "border edge" after the capping. It use two "Set Topology" instead of one, but it is fast because there is no complex array operations to switch between component types.

About, the addon :

The idea is to add any new ICE topology compound published here in it. it also include a python plugin to define some menu callbacks used by the compound(s).

For this first version 0.1, it is very small, there is just the Cap Borders compound, and the plugin will load a menu in the right click contextual menu when the polymesh is in sub-component selection mode.

Just select a vertex on the border before clicking on the menu to cap the corresponding borders.

I will increment the addon version at each update, and you willl need to remove the old one before installing the new one !

Cheers !

Guillaume

[Fabricio Chamon]

"To do this, it is using the point position and the first strand
position as a tangent basis. So maybe Melena system create the first
strand position on the point position ?"

yes, took me some minutes to figure this out when trying the "create
extrusion along strands" with my strand tree compounds. That's exactly
what I do, create the first strand segment on the same position as my
points. An alternative would be provide the users a "start strand
segment index" option on the compound, so that the meshing starts at a
defined index on the strandpostiion array.

@eugen: I'm already looking into the corner mitering thing. few more
days for an update... =)

[Fabricio Chamon]

Thanks a lot for the workshop and compound Guillaume. It was a nice
challenge! Willing to see much more coming...

[Guillaume Laforge]

>  An alternative would be provide the users a "start strand segment index"

Yep that's an idea. But from my point of view, the first strand position should not be the same that point position. I know that several factory compounds got it like this (strandposition[0] = pointposition) but honestly, it doesn't make sense to me.

But we will think about it as this compound got some other problems that should be fixed btw.

Guillaume

[Guillaume Laforge]

I just started a new one ;)

[Claude Vervoort]

Thanks Guillaume for initiating this. That gave me a good excuse to start playing with ICE modelling. I did not want to look at any answer, so it took me quite some experiments to get something that somewhat works (the documentation is quite good, if a bit succinct) . I think I am due to a oh! moment when I will look at the actual solution!

Doing ICE modelling is definitely a mind set to acquire (at least for me), especially the fact that you work in a given context. So for example I did not see a simple way from a vertex to get the other connected vertices. The only way I have found to do this is:
- First collect the connected edges (in vertex context, filtering the vertices by vertex id) and get the associated edges
- then in another subtree executing in edge context, filter by the edges just found and get the associated vertices.

Thanks again for setting this up! If interested you can set my commented ICE Tree at: http://claudeonthe.net/images/si/cap_ice_modeling_challenge.jpg One key element missing is to produce the cap in the correct winding order. For that I am not sure.

Anyway time to look at the answer and move on to the next challenge :)

Claude

[Guillaume Laforge]

Hi Claude,

Your tree is rather good, and it looks like you are not an ICE beginner :), are you ?

>  I think I am due to a oh! moment when I will look at the actual solution!

Well, you will find my solution not so interesting from an educational point of view ;). I thought that this scenario would be a good opportunity to learn how to switch between contexts. But in fact, I found that using the PointNeighbors attribute was the way to do it and so I skipped this   part :-/.

> So for example I did not see a simple way from a vertex to get the other connected vertices. 

The PointNeighbors attribute do the job for you (finding the point locations connected by an edge to the current point) ;).

But it is always good to know how to do it without this attribute, (and so your comment is really useful) because sometime, we can't deal with point locators to get the data if we are not in per point context. And yes, you are right about the workflow (getting connected edges etc...)

For those interested on how to switch between context here is a sample scene :

http://dl.dropbox.com/u/5533643/Softimage/GetPointNeighbors.scn

The idea is to switch from a per element context to a per object context to store an array of indices. This data can be accessed without problem from all per element contexts.

Cheers,

Guillaume 

[Claude Vervoort]

I have been on the ICE before but not in the modeling arena though, and not for long enough since I was not aware at all of pointNeighbors (when I think how much time I spent trying to get to those :) ). Thanks for the scene too!

BTW when I try to run the plugin here, I have this error:

 ERROR : 21000-EDIT-PrivateGetCompoundConstructionMode - Unspecified failure - [line 712 in D:\Program Files\Autodesk\Softimage 2012\Application\DSScripts\operators.vbs]
Application.ApplyICEOp("Cap Borders", "", "", "siUnspecified")
# ERROR : Traceback (most recent call last):
#   File "<Script Block 2>", line 35, in CapBorders_Callback
#     ICETree = si.ApplyICEOp( "Cap Borders", None, None, C.siUnspecified )
#   File "<COMObject XSI.Application>", line 2, in ApplyICEOp
# COM Error: Unspecified error (0x-7fffbffb) - [line 34 in C:\Users\Claude\Autodesk\Softimage_2012\Addons\ICEModelingTools.0.1\Application\Plugins\ICEModelingMenuPlugin.py]

I haven't looked too much into it, don't spend anytime on it but if you have a quick idea about what I should look at, i'll take it.


Claude

[Guillaume Laforge]

Hi Claude,

It looks like you don't have python working correctly on your machine. I'm not an expert in this area btw. First thing I would try is to open a Softimage command prompt and run : runonce.bat

If it doesn't help, I'm sure you will find a Softimage Python specialist here to help you :)

Cheers

Guillaume

[Claude Vervoort]

Oh thanks for the pointer, i've played a bit with Python on SI before, but that is my fresh 2012 so maybe I need to update something...

Claude

[Stephen Blair]

I get the same error, so I'll check it out...

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Claude Vervoort
Sent: May-10-11 7:57 AM
To: soft...@listproc.autodesk.com

Subject: Re: ICE Modeling workshop : The Capping Tool

Oh thanks for the pointer, i've played a bit with Python on SI before, but that is my fresh 2012 so maybe I need to update something...

Claude

On Tue, May 10, 2011 at 5:40 AM, Guillaume Laforge <guillaume....@gmail.com<mailto:guillaume....@gmail.com>> wrote:
Hi Claude,

It looks like you don't have python working correctly on your machine. I'm not an expert in this area btw. First thing I would try is to open a Softimage command prompt and run : runonce.bat

If it doesn't help, I'm sure you will find a Softimage Python specialist here to help you :)

Cheers

Guillaume

On Mon, May 9, 2011 at 10:59 PM, Claude Vervoort <claude....@gmail.com<mailto:claude....@gmail.com>> wrote:
I have been on the ICE before but not in the modeling arena though, and not for long enough since I was not aware at all of pointNeighbors (when I think how much time I spent trying to get to those :) ). Thanks for the scene too!

BTW when I try to run the plugin here, I have this error:

ERROR : 21000-EDIT-PrivateGetCompoundConstructionMode - Unspecified failure - [line 712 in D:\Program Files\Autodesk\Softimage 2012\Application\DSScripts\operators.vbs]
Application.ApplyICEOp("Cap Borders", "", "", "siUnspecified")
# ERROR : Traceback (most recent call last):
# File "<Script Block 2>", line 35, in CapBorders_Callback
# ICETree = si.ApplyICEOp( "Cap Borders", None, None, C.siUnspecified )
# File "<COMObject XSI.Application>", line 2, in ApplyICEOp
# COM Error: Unspecified error (0x-7fffbffb) - [line 34 in C:\Users\Claude\Autodesk\Softimage_2012\Addons\ICEModelingTools.0.1\Application\Plugins\ICEModelingMenuPlugin.py]

I haven't looked too much into it, don't spend anytime on it but if you have a quick idea about what I should look at, i'll take it.

Claude

On Mon, May 9, 2011 at 12:30 PM, Guillaume Laforge <guillaume....@gmail.com<mailto:guillaume....@gmail.com>> wrote:
Hi Claude,

Your tree is rather good, and it looks like you are not an ICE beginner :), are you ?

> I think I am due to a oh! moment when I will look at the actual solution!

Well, you will find my solution not so interesting from an educational point of view ;). I thought that this scenario would be a good opportunity to learn how to switch between contexts. But in fact, I found that using the PointNeighbors attribute was the way to do it and so I skipped this part :-/.

> So for example I did not see a simple way from a vertex to get the other connected vertices.

The PointNeighbors attribute do the job for you (finding the point locations connected by an edge to the current point) ;).

But it is always good to know how to do it without this attribute, (and so your comment is really useful) because sometime, we can't deal with point locators to get the data if we are not in per point context. And yes, you are right about the workflow (getting connected edges etc...)

For those interested on how to switch between context here is a sample scene :

http://dl.dropbox.com/u/5533643/Softimage/GetPointNeighbors.scn
The idea is to switch from a per element context to a per object context to store an array of indices. This data can be accessed without problem from all per element contexts.

Cheers,

Guillaume

[Stephen Blair]

Hi

In the ICE Tree viewer, open the Preset Manager and click the Refresh button.
Check that Cap Borders is available in the Preset Manager.

After that, the Cap Borders menu command should work (it wasn't finding the compound).

A restart might fix the problem too, but I didn't try that.

Thanks

[guillaume laforge]

Thanks Stephen for the help :),

Addon install won't do a scan of the preset manager, so it explains the pb on the first try

Guillaume Laforge

Sent from my iPhone

> <winmail.dat>

[Fabricio Chamon]

After 2 very busy weeks, I found some time for an update:
http://vimeo.com/23859554

new features:

- correct corner mitering (thanks Eugen for providing the formula and idea)
- support for multiple path subcurves (choose subcurve index or use
all subcurves)
- subdV/subdU renamed to Path curve and Profile curve for better readability
- corrected cross section rotations (non-flipping normals) - there was
a bug in the previous version
- constraint to path flag
- split radius and roll along curve controls into "control compounds"
for cleaner/smaller interface
- all main parameters are now array based, which means that
radius/roll/start/end, etc can be controlled per subcurve.
- mesh has a new Self.PathSubcurveIndex variable that can be used to
modulate any extrusion effect (also per subcurve).

roadmap:

- support for multiple profile subcurves
- support for closed curves

compounds are attached. Let me know what you think, bugs, requests..etc.
Also should mention that the correct cross sections rotations were
"stolen"/adapted from Guillaume's Extrusion along strands compound.
(thanks Guillaume)

ps: Eugen, when are you planning to release your curve tools ? I'm
sure it would help me improving the compounds...new ideas, etc

[Fabricio Chamon]

"roadmap:

- support for multiple profile subcurves
- support for closed curves"

...oh and sure...UVs

[Christopher Tedin]

Awesome.

[Eugen Sares]

Hi!

On Tue, 17 May 2011 21:26:32 +0200, Fabricio Chamon <xsim...@gmail.com>
wrote:

> After 2 very busy weeks, I found some time for an update:

First, it's so great so see your Operator evolve! Brilliant job!
Did you release it somewhere? Will you charge something for it?
Need a "beta-tester"... ? ;)

My CurveTools are actually already released, but only on xsiforum.de.
I'd like to do a simple video demo first before I put it on the "mighty"
mailinglist, and I'd also like to finish support for Isopoints in
SplitSubcurves (trickier than in looked).
Got a hint from Alok Gandhi - thanks to him!! - only 2 days ago for that,
and didn't find the time to finish it yet.

Soon!!
Best regards,
Eugen

[Eugen Sares]

Forget that release question, you attached it!
The hour is late...
.ￜ}

On Wed, 18 May 2011 00:07:58 +0200, Eugen Sares <soft...@keyvis.at>
wrote:

[Eugen Sares]

Fabricio,
here a few suggestions how you to boost "Extrusion along Curve" to the
swiss army knife of all extrusion ops:

- Support for multiple open/closed profile/path Subcurves

- UVs
(like you said)

- Script to apply it comfortably, maybe in menu Model>Create>PolyMesh
(Should ICE modeling ops not reside somewhere under ICE?)

- If no path Curve is connected, the Operator could extrude along an Axis,
with param X/Y/Z to choose.
This would put two Ops in one - no additional "Extrude along Axis" needed
anymore. Very handy!
So if neither a Profile nor a Path is connected, a Cylinder is generated.

- Important: subdivision params should define the subdivs on a Segment
(Curve part between two Knots), not along the whole Curve (both path and
profile)!
In other words, there should always be a subdivision on every Curve Knot.
If the subdiv param is cranked down to 1, Segments become linear.
It's impractical having to adapt the number of path subdivs when the
number of points/knots changes.
The factory "Extrusion along Curve" Op works that way, too, also the
"Hardware display" node of a Curve (degree 2 or 3).

- Experimental: define Material IDs per Curve segment, and give that ID to
the created Polygons (3ds max has this).
That way, it won't be necessary to create Material Clusters on the
polymesh, because Clusters won't update with Curve changes, and the
Material assignment gets messed up.
There's no "Segment" Component in Softimage like in max yet... I wonder if
there a way to store additional information along a Curve that updates
automatically when it changes?

For convenience:
- Mirror Profile across X/Y

- Shift/Translate Profile X/Y

What do you think?
Best,
Eugen

[Fabricio Chamon]

I think those are all great improvements!
thanks for the feedback Eugen. Let's see if I can handle all your requests.. =)

already working on an update...

[Stefan Kubicek]

One more: adaptive subdivisions depending on curvature

I no one else wants it and if OK with Fabricio I'd volunteer for creating proper menu entries and a custom command that applies the compound (and ICE Tree if not already present) , sets and connects the required Get Data nodes and inspects the PPG's (as long as Ctrl is not pressed) for a streamlined workflow that is more in line with Softimage's modeling paradigms.

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Stefan Kubicek Co-founder
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1050 Vienna Wehrgasse 9 Austria
Phone: +43/699/12614231
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[Eugen Sares]

*thumbs up*
You know, this Operator of yours is among the things I always missed in SI
since I switched to Softimage.
The others are:
- better Curve Tools - did my best as an amateur coder to fill some of
those holes.
- a better Renderer for complex GI scenes than mray - Arnold and VRay are
underways.

Not much left to justify using ol' 3ds max shortly... for any job.

On Wed, 18 May 2011 15:19:53 +0200, Fabricio Chamon <xsim...@gmail.com>
wrote:

> I think those are all great improvements!

[Fabricio Chamon]

"One more: adaptive subdivisions depending on curvature" - added to the list!
thanks Stefan. And feel free to add menu entries/custom commands, in
the end I'll pack everything inside an addon.

[Kim Aldis]

two things with extrusion; uneven segments and sharp corners. I'm going back a few years without having touched any of this so bear with me. You may also have considered this Fabricio, I only skimmed your video.

If your control points aren't evenly spread then the segments in your curve are going to vary considerably in their length as you move along your curve. This is a problem to some degree for resolution but mostly it's a horrible thing to have to deal with when you're texturing.

If you have sharp corners in your curve, segment edges will probably miss the corner points and you'll get horrible detail there. Worse still, if you're animating your curve you'll get nasty animated artefacts as the segment edges kind of travel over the corners.

You can get round this things to some degree by calculating points on a per segment basis, working out how many segments of a particular length you need for each segment. This will be a non integer value so you tweak the length for each segment to make an integer fit. The segments won't be exactly the same length but they'll be close enough not to matter.

Hope this makes sense.

[Fabricio Chamon]

Hey Kim, thanks for having your word on it. Yeah, I'm definitely going
change the cross sections subdivision method.

I'm considering 3 subdivision types:

- Segment length dependent (the way it is right now)
- Evenly distributed, fixed (equally spread, but does not change
number of cross sections after curve tweaking)
- Evenly distributed, spacing ratio (equally spread, and changes the
number of cross sections in relation to the path curve length)

all three should produce good UVs (first one will have stretching
compensation for the changing segment lengths), with u/v scaling and
independent controls for the capping parts.

Talking about the segment angles, maybe I could get the closest cross
section to any sharp corner and snap it to the corner depending on an
angle threshold (let's say less than 90 degree angles), this could
avoid artefacts in animated extrusions.

what do you think ?

again, thanks for the tips.

[Kim Aldis]

kind of what I did but rather than snapping, I tweaked the segment width to make it all fit. If you snap to the corner that last segment can sometimes be noticeably larger than the rest. This is what I did in tinyExtrude, it worked well enough that I was thinking about a general purpose tool for spline interpolation. The corner issue is just as much of a problem when animating along splines.

[Eugen Sares]

Hi Fabricio,
just curious about the progress of your extrude compound.
Would be cool to have it in the toolbox... there's a job up ahead where it
might come in handy.
Cheers!
Eugen

[Fabricio Chamon]

Hi Eugen,

still working on it on my spare time. got some new features working already:

- Default Extrusion Start/End vectors (builds a cylinder in case
there's no path curve connected)
- support for open/closed profile and path curves (user has to check a
flag as there's no way in ice to know if a curve is open or closed. Or
is there?)
- new path subdivision rules:
- Segment Length Based
- Evenly Spaced - Fixed
- Evenly Spaced - Spacing Ratio
- Wall (optimized) - 1 to 1 extrusion segment for each curve segment
- Custom Point Positions (uses an user provided 3d vector array for
path point positions)
- Per component (vertex and poly) ice attributes (cross section index,
cross section normalized, path subcurve) - which can be further used
for modulating effects along curve, for material assignig, and so
on...

actually it needs a little more testing as the compound grew a lot in
features. I have to check if all combinations are working (subcurve
mode vs. subcurve rule vs. using arrays for parameters...etc)

I'll make a video of the new features and post later today along with
the updated compounds + sample scene. Maybe you can help me testing
all the stuff =)

[Christopher Tedin]

Awesome, thanks!