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I dont actually see what you're saying here.... this is not a matter of way of working only ... i mean .. extruding polygon aint a way to model?... if in houdini there's something different to extrude polygons which gives me same result.. i'm here to listen and learn.. totally. But we're talking about a pretty "basis" of the polygonal modeling tecnique.. and not about a workflow..dont get me wrong here but.. i dont agree.

I tried the symmetry.. and this dont fix the polygonal scaling problem... and XSI have symmetry for many operator as well (not just extrusion)... but i'm not complaining about what's missing in houdini or what.. believe me I'm pointing all my effort to learn Houdini in every type of tasks, modeling included.... and a head... or a mouse.. or anything which is not "procedural"... wont be "procedurally" done.. so "static" tools like extrusion and duplication of edge, points and polygons are things that should just work out of the box..

I appreciate the Mario comments.. but i wont surely create an OTL or anything else for "just" extruding my polygons... i wont able to do it eighter.

Again, dont get me wrong.. I'm seriously converting my mind (and its hard after 10 years of Softimage "school") to Houdini's way of working... but i'm sure some basis of 3D and CG are the same... and some steps will be the same as well... but again.. if there's an alternative to polyextrude... please show me... cause by now.. i still cant extrude those torus polygons and get those scaled properly.. symmetry or not, global or local. sorry.

cheers.

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One other problem I've spotted (didn't spend long trying to figure out if there was already an answer) When using the global transform how do you specify the pivot point? Since there is no handle and no pivot channels where is it? I was getting some really whacky rotations using global because the pivot point seemed to be miles away from where I needed it. I'm sure there must be something obvious I missed.

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Actually I think what you're experiencing here is a new bug that may have been introduced with the new shear parameters.

George, do we still need to send in an official support call for this or can we assume that is done?

I'll submit an RFE for adding more symmetry options, but if you'd like to add a specific case, please send it on into support and they can attach it to the RFE.

Would quaternion rotations remove the Euler flip?

Hmm.. I'm not sure. But the bigger problem, I think, is that the local frame will still be computed from the main face and the resulting rotated frame might still be completely wrong for your other faces...?

cause by now.. i still cant extrude those torus polygons and get those scaled properly.. symmetry or not, global or local. sorry.

Hmm.. that's surprising. Are you sure doing inset won't solve your problem? Inset is what I use when I want to scale my faces in -- it works much better than scaling because it should give you a nice uniform spacing around the edges... but inset doesn't do non-uniform insetting... if inset doesn't give you what you want, could you describe the kind of scaling you're looking for?

Thanks!

George.

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Hi George,

the easier way to show you what II was trying to archieve is by the following images...

post-490-1139585487_thumb.jpg

- the houdini torus is the torus with extruded polygons and then I used inset (0.25) to scale down the selected polygons... the result talk itself.

post-490-1139585499_thumb.jpg

- the xsi torus.. shows just an example of what I'd often need.. scaling on the Y axis (which is Z for Houdini .. i mean the normal direction).. and then the X axis ... which in xsi is like the X axis of the bouding box of my selection.. which makes my polygons scale uniformly and not considering each one his own X orientation (which i find smart and clean).

this is just a simple example about what i talk about when i say there's no really a simple approach with polyextrude... i mean .. i have not much control over "which" is the axis system to be used... if you know Xsi a bit.. I'm talking about COG/ LOCAL/GLOBAL ... where COG puts the pivot at the center of the current selection (points, edges, polygons or object..) and orient it based on its bounding box... in the case of polygons this makes really easy to scale 'em in a easy manner..

in houdini .. if i use the handle to scale the polygons on X axis .. they just get crazy.. and if using global.. its not that handy since 1)pivot goes to origin 2) you dont work usually with "world oriented polygon" when modeling complicated objects.. that's for sure.

i guess what its missing there to fix all this (just my opinion) would be something like COG (center of geometry) mode.. other than local and global... that would make everything easier i guess.

hope this helps.

cheers.

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I dont actually see what you're saying here.... this is not a matter of way of working only ... i mean .. extruding polygon aint a way to model?... if in houdini there's something different to extrude polygons which gives me same result.. i'm here to listen and learn.. totally. But we're talking about a pretty "basis" of the polygonal modeling tecnique.. and not about a workflow..dont get me wrong here but.. i dont agree.

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I didn't want to muddy the water here. I totally agree with you polyextrude should work correctly, and from your examples I think I have even more problems with it than you have even found.

But if you are talking about modelling a character for example I know there are other ways that don't use polyextrude. That's how come I never really use it. My personal preferred way is different, mostly based on using the curve sop, it's just a diiferent way of working. But I'm not suggesting you change just to fit in with the fact that polyextrude isn't 100%. Should have kept my mouth shut really. ;)

I've have examples at work (i'll try and send to support) where using the global translate messes up the extrude to the extent that points move around randomly. Really bad, no idea what is going on there. I think the whole sop needs completely testing in all sorts of situations. Even testing it on a torus doesn't show up all the problem you get when free form modelling with it.

The only good thing is that at least the local handle aligns itself with the first face, I'm still waiting for that to arrive in the edit sop, it's so painful that the handle defaults to aligning with the world axes. As you say how often do polys line up with the world axes?

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stuff and pictures

I know you probably don't want to hear this, but as a workaround, you can limit your extrudes to transforms only and then append an edit to do your scaling or rotating. That's what I do, pretty much intuitively, which is probably why I didn't understand what the problem was.

I agree, the SOP should deffinitely fixed to give more desireable results when scaling and rotating, but there are ways to work with it for now, if you really need to use it.

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in houdini .. if i use the handle to scale the polygons on X axis .. they just get crazy.. and if using global.. its not that handy since 1)pivot goes to origin 2) you dont work usually with "world oriented polygon" when modeling complicated objects.. that's for sure.

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Thanks that does make it a bit clearer. As for getting more control over the global extrusion handle, does it work for you if you detach the handle (') and then move the handle to the pivot location and reattach (' again)? That may give you more control.

Also, if it sin't too much trouble, would it be possible to post an .obj or .geo of the result you'd like to do in a single polyextrude?

Thanks!

George.

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Unfortunately, it also seems that XSI does the basic and most used stuff much easier than PolyExtrude.

Dragos

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Both have their strengths but xsi's polyextrude is VERY limited.

Try to make a constant width shell out of a mesh...you have to make several operations, you'll get thinner shell at boundaries and folds and if there are more than 10 faces you are likely to wait an hour for the polygons to move locally ;)

It is shit.

Of course you are able to use Helge Matee solidify2 but juggling with weight map when it's not needed is a real drawback.

my 5 c's

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The whole local coordsys thing probably

isn't going to happen; its been requested

for ages (since V5 or 6 i think), but not by

clients it seems. There are some very nice

modelling tools in there but they are

handicapped somewhat (only world coordsys for

'manual' modeling and almost no dynamic output

grouping and spatial selection for procedural

modelling). Still, I'd prefer it to max for

most modelling, just have to accept making

eyeballed manual edits to fix things.

-cpb

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Still, I'd prefer it to max for

most modelling, just have to accept making

eyeballed manual edits to fix things.

-cpb

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Whenever I have to work in max...I always prefer a sofa.

The BEST and unique thing about modelling in XSI is the transient pivot and constraining to axes. I try houdini hard now and have some ideas about basic modelling improvements to post later.

It's all about these tiny little thingies that make you love one software and hate the other.

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(only world coordsys for

'manual' modeling and almost no dynamic output

grouping and spatial selection for procedural

modelling).

-cpb

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They have to at least add orient to polygon for handles as bare minimum, one day it will happen it's so easy to add it hurts. :(

As to spatial grouping I'm interested, what do you mean exactly? I think you posted about it before somewhere but can't remember where, what are the situations where you would use it? It might be something simple to write a sop for.

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Cheers for those links, seems I was involved in most of those discussions :P its interesting to read back old ideas to see if they still seem relevent.

This is maybe going off topic but I still think the idea of groups supporting weighting/falloff would be a good one. I know you can do it with attributes etc but it just means having so many extra sops and otls to get it to work. In my mind it fits so neatly with what is already there. For backwards compatibilty everything would get 100% memebership by default. And to pick up on the problem that a point is either in a group or not for sops like delete you simply use a threshold value. Again for backwards compatibility it would default to 100% - so only delete points that are in the group with 100% weight. But the option would be to delete points that are over a user specified weight.

Anyway as to spatial grouping it would be easy to add a sop to create a group based on proximity but I'm still struggling to find an example of where this is really useful, please post if anyone has one.

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