Wierd shading problem in maya

[StefanStavrev]

HEy

First of all : very bad wire.You should work more on your modeling skills :)

About the problem i had it long time ago .

I solved it like this :

1.Delete every single material in hypershade

2.Delete scene's hystory

3.Check the input and output conections of my objects in the hypergraph and delete
"problematic nodes" - for example when you convert a poly to sub and then go undo,
a subdivision surface node may still be connected to the poly and what you got is two
nodes resulting in one surface, so when you asign material to the poly you have troubles.

4.Make uv's for every object

5.Asign new materials to my objects

That's it :) Hope i helped

[maunilpatel]

HEy

First of all : very bad wire.You should work more on your modeling skills :)

About the problem i had it long time ago .

I solved it like this :

1.Delete every single material in hypershade

2.Delete scene's hystory

3.Check the input and output conections of my objects in the hypergraph and delete
"problematic nodes" - for example when you convert a poly to sub and then go undo,
a subdivision surface node may still be connected to the poly and what you got is two
nodes resulting in one surface, so when you asign material to the poly you have troubles.

4.Make uv's for every object

5.Asign new materials to my objects

That's it :) Hope i helped

I will try to do what you have just said..
And about improving my modeling skills.. I am a learner.. so don't deep knowledge about modeling.. though can you tell me how can I improve?

[StefanStavrev]

Modeling is something that you will learn best with work.

Take some pictures from the internet and try to build that.Learn from your mistakes.Try to get every next piece better and uniqe.

Get some books or video tutorials... The internet is FULL of them...

check this site : www.3d-palace.com - Great FREE place to start your modeling improvement.Just register and download some maya tutorials.

When i was in the START of 3d, the Jaguar XJ220 tutorial helped me a lot.

Be carefull with your edges of your objects.Use BEVEL as much as you can.

Now try to get as better as you can in modeling TECH STUFF : mobile phones,cars,robots,enviornments...

Then take the next step and start learning ANATOMY, and model the human.

But remember the most important thing : Decide as what you want to get a job in future.

1. modeling artist
2.texturing artist
3. rigging artist
4.animating artist
..........................bla bla

If you now start learning modeling, don't even think about the others.Cause trust me,modeling itself is much bigger than you think...

Hope i kinda helped

Take care :)

[Emil3d]

Maunil, regarding your topology I would say that if this is the final result - meaning no further editing of topology and geometry, then it seems acceptable to me.

This kind of topology is usually the result of subdivision surfaces converted to polygons before rendering with the adaptive method and your wireframe suggests decent original topology of the subdiv surfaces that flows properly along the shape.

This technique should work well for non deformable hard shelf surfaces like cars. Since the topology is a result of conversion calculations of originally smooth subdivision surfaces, the resulting edges ending at ngons are placed perfectly in the middle of rectangular quads which will allow smooth shading when rendered.

[StefanStavrev]

I would have to disagree with that.I think it is an awfull wire...

No offense of course :)

[maunilpatel]

I would have to disagree with that.I think it is an awfull wire...

No offense of course :)

can you please tell me, what is the good example of good wire? I want to learn as much as possible..

I converted subdv to polygons using following settings.
Tessellation method: adaptive
Division Per Face: 1
Original Object: Replace
share UVs: (ticked)

and here you can see full wire,

http://img19.imageshack.us/img19/6946/temp3nc4.jpg

[maunilpatel]

Maunil, regarding your topology I would say that if this is the final result - meaning no further editing of topology and geometry, then it seems acceptable to me.

This kind of topology is usually the result of subdivision surfaces converted to polygons before rendering with the adaptive method and your wireframe suggests decent original topology of the subdiv surfaces that flows properly along the shape.

This technique should work well for non deformable hard shelf surfaces like cars. Since the topology is a result of conversion calculations of originally smooth subdivision surfaces, the resulting edges ending at ngons are placed perfectly in the middle of rectangular quads which will allow smooth shading when rendered.

The actuall shading thing happened when I started extracting the part of car(like extracting door, and roof and stuff..) thanks for replying..

[Emil3d]

If you want to avoid the ngons, convert with the Vertices option and increase the level number until you get the desired detail. This will make everything quads which as I suggested earlier is more flexible for deformations and additional editing but this by itself doesn’t fix the topology in terms of flow or design.

While the wire of the door you posted initially is generally OK, there are some spots on your last screenshot of the whole car that don't flow nicely along the shape and under certain conditions, my cause undesirable shading. I highlighted some of them

http://i111.photobucket.com/albums/n129/Emil3d/temp3nc4-1.jpg

While you are working with subdivisions press the "`" key (the one under Esc) to switch to shaded poly proxy mode which will allow you to examine the underlined topology in simplified low res version. You should actually post a wireframe of that geometry

The shading can be caused by many different things including video card display problems. If you want, save a piece of the problem geometry and upload the file here, I’ll check it for you.

[Emil3d]

I would have to disagree with that.I think it is an awfull wire...While it may look awful depending on the taste, do you know of any problems that it may cause other than those already mentioned?

[maunilpatel]

so you meant to say, the one in first screenshot is better then the second one..
First one, I tried to convert hood of the car through verticies at level 3.
Second one is the same old one..

http://img208.imageshack.us/img208/7965/tempkm5.jpg
http://img208.imageshack.us/img208/4062/temp2ue3.jpg

[StefanStavrev]

While it may look awful depending on the taste, do you know of any problems that it may cause other than those already mentioned?

That is just not good modeling man.It is awfull modeling...

Good modeling means as equally as possible distanced faces.That means easier texturing,that means correct reflections... bla bla :)

[Emil3d]

so you meant to say, the one in first screenshot is better then the second one..
First one, I tried to convert hood of the car through verticies at level 3.
Second one is the same old one. Not exactly, what I meant is that, if this is your final result, and you are not going to make any further geometry edits or surface deformations, the second (old) one is sufficient and converting it to all quads topology will not make any difference in the final rendered result but only increase the face count unnecessarily.

But if you intend to deform and/or modify the surface with things like the sculpt brush or edge loops edits then all quads topology of the first (new) one is better.

By the way, level 3 is adding a lot of division to your surface that may be unnecessary depending on the distance from the camera. Try lower or level 1 first and decide if you need more details after a test rendering.

Both topologies however, have flow and design problems like those that I highlighted earlier and they are not going to be fixed by simply trying to convert to polygons with different options.
To fix this, it is most efficient to go back at the subdivision editing stage, and use the low res poly proxy mode where it is easier to redirect the topology flow by removing/adding faces and spinning edges.

As I suggested earlier, posting a screen shot of the topology in shaded poly proxy mode while at the subdiv stage, will make it easier to give you more specific topology suggestions.

[Emil3d]

That is just not good modeling man.It is awfull modeling...
Good modeling means as equally as possible distanced faces.That means easier texturing,that means correct reflections... bla bla Regarding shading including reflections, it is not about avoiding faces with different sizes, topology, and density concentrations but how gradually those different areas and face topology merge into each other and how all this is laid out. In that respect, although there is place for improvement, I wouldn’t describe the Maunil’s topology as awful.
It is highly inefficient to use a topology that subdivides the entire surface to faces with a size needed for the finest details. Even with stitched NURBS, people use patches with 2 to 1 and higher ratio to reduce detail redundancy on areas that don’t need any details.

Texturing is not a problem at all since the UVs can be mapped on the lo res poly proxy cage before or at the subdiv stage and as far as I know that’s the proper workflow when texturing subdivs and in general for geometry that involves low to high res conversion.

[StefanStavrev]

Sorry man .You did not convinced me :)

I still think that wire is awfull.

[Emil3d]

Sorry man .You did not convinced me :)No problem man:) I just thought I would share my thoughts in case somebody find them helpful.
Have a nice day.

[maunilpatel]

I got you guys' point.. I will try to get it better in my next model.. Those ngons were cause of some extra edges and I tried to remove it, and it came out pretty good, but I can't edit eveything now, since it's close to finish.. I will keep these in mind next time.. thanks for all help..

[Emil3d]

Hey StefanStavrev, I’m curious to hear your opinion about this car wire and what do you think of it.


http://i111.photobucket.com/albums/n129/Emil3d/Stavrev.jpgThat is just not good modeling man.It is awfull modeling...
Good modeling means as equally as possible distanced faces. That means easier texturing, that means correct reflections... bla bla :)I know that by your definition it should be awful since a lot of faces are distanced differently with different sizes and topologies, but I would like you to confirm and say if this is so about this particular wire.

I would appreciate your reply:).

[StefanStavrev]

Hey emil :)

Yea this is awfull too man.Too many polygons and bad wire ( result of converting from sub to poly)

I supose you had a poly model , then converted to sub and then from sub again to poly...

If you do that, when you convert from sub to poly use the Uniform option.A wonderfull option :)

By the way, as you can see this process of modeling gets you too many polygons, so i would sugest you to forget about it and try to use polygons only...Use split polygon tool and insert edge loop tool to make it smooth.That is what i do to all my models,and so far people love them :)

Peace :)

[Emil3d]

I appreciate your reply Stefan. :thumbsup:

Before I continue I have to warn you that the purpose of my previous post was actually to see if I can convince you that this method can give very good results, and the problems with reflections and textures that you suggested with this method are not valid. I was inspired to do this after you posted this statementSorry man .You did not convinced me :)
I still think that wire is awfull.Since I strongly believe that my suggestions are valid and helpful and yours are not, my question to you now is:
Do you think that you are a person that can be convinced? And if so what would convince you that my suggestions are valid and yours are not? I know that the reasons I mentioned were not enough for you but do you need some sort of proof that this method is good and what kind of proof can make you change your mind, for example nice rendering result, or master who recommends this method or anything else that you can accept?

As far as I know you are an open minded guy and wouldn’t mind a talk like this.:):):) Otherwise if you think that I’m playing with, or making fun of you, or feel in any way offended, please let me know and I’ll stop this immediately, since this is not my purpose. May purpose is really to convince you that I am right and I’m preparing a convince trap for you:):):)

[StefanStavrev]

Hey man :)

Look, ask some pro guy.He will tell you that wires sucks too... :)

Peace :)

[Mangaroo]

I wouldnt call that awful at all. Infact, its looking good, did you fix the shading problem?

[Caypiranha]

I wouldnt call that awful at all. Infact, its looking good, did you fix the shading problem?


all in all i would say : RENDER it - and when it looks PERFEKT...(!!!)... then it´s:ok! (since nobody will look you under the hood when the work is done... but that could also be a fatal way... =))

but I also think, that there are some things not very good. In the doors, there are too many faces. Try to convert the polygonmesh in another way.. this strange division style is´nt that cool for that. go over "counts" or "vertices" (in the Convertoptionbox).. and realy avoid more then 4 edges to an Vertice. it will come in certain corners dodgy..

[Emil3d]

:sad:Stefan, I’m kind of disappointed that you didn’t bother to answer directly these questions of mine Do you think that you are a person that can be convinced? And if so what would convince you that my suggestions are valid and yours are not? I know that the reasons I mentioned were not enough for you but do you need some sort of proof that this method is good and what kind of proof can make you change your mind, for example nice rendering result, or master who recommends this method or anything else that you can accept?Your answered this:…Look, ask some pro guy.He will tell you that wires sucks too... From your answer I take that if some pro guy is using, recommending, teaching, and demonstrating nice results with this method that will prove to you that I was right and you were wrong.

Well if so, then here’s the proof. The “awful” wire that I posted is not mine, it was created by Kyle Green, in-house Lead Technical and 3D Artist and Senior Art Director at Digitaltutors. You can read who he is by clicking on the following link
http://www.digitaltutors.com/chit_chat/showthread.php?t=461

The following images are from the Digitaltutors site showing excellent results produced from Kyle using this particular "awful" model that I posted earlier

http://i111.photobucket.com/albums/n129/Emil3d/product_image.jpg

http://i111.photobucket.com/albums/n129/Emil3d/product_image2.jpg

http://i111.photobucket.com/albums/n129/Emil3d/product_image3.jpg

This is all in 2 kits of training video to teach a nice and viable method that gives attractive results

http://www.digitaltutors.com/digital_tutors/images/store/products/street_racer_addon_store.jpg


Follow this link http://www.digitaltutors.com/digital_tutors/display_video_store.php?vid=543 and when an oragne bar that says click to play video appears at the bottom, click on it, to play part of the training video to see with your own eyes how Kyle makes the excellent shading on this particular model with that particular wireframe in a lesson intended to teach people like you who don’t know that this method gives excellent results and efficiency.

You recommended to me to ask a pro and now I’m letting you watch a pro demonstrating nice results with a model that you labeled as awful.

I would really apreciate if you answer this question directly: Would you now admit that I was right or you are still not convinced and insist that this method gives bad results?

See I’m very easy and will change my mind instantly admitting that you are right and I was wrong if you give me a simple proof. Just create and upload a scene with a textured subdivision object receiving reflections which demonstrates problems with reflections or any shading problems that are result of the conversion to polygons with the adaptive option. I will not only change my mind but I will be also very grateful to you for helping me learn new things.:)

[Emil3d]

but I also think, that there are some things not very good. In the doors, there are too many faces. Try to convert the polygonmesh in another way.. this strange division style is´nt that cool for that. go over "counts" or "vertices" (in the Convertoptionbox).. and realy avoid more then 4 edges to an Vertice. it will come in certain corners dodgy..Actually quite the opposite this method uses smooth and gradual 2 to 1 ratio transitions (read my earlier explanation in this thread about how this works). This reduces the face count perfectly smoothly by getting rid of geometry density on areas of the surface that don’t need details. This makes the surface lighter, more efficient, and performs better.

As I said earlier if you make the whole surface uniformly all quads with a density needed for the finest details you will increase the poly count tremendously with unnecessary faces covering areas that don’t need any details.
The density concentration and lack of it on certain areas on the model in question, like the door for example, is there for a reason. That is: more detail = more faces, less detail = less faces. The following images illustrate this clearly

http://i111.photobucket.com/albums/n129/Emil3d/car.jpg


http://i111.photobucket.com/albums/n129/Emil3d/car2.jpg


Read my suggestion posted earlier about where this method works well and where it should be avoid.

[StefanStavrev]

I have seen that tutorial before :)

I keep my opinion that is bad wire :)

ps : Stop doing this.You won't convince me man :) ...

Peace

[Emil3d]

... Stop doing this.You won't convince me man :) ...Thanks. Finally a direct answer to one of my previous questions “ Do you think that you are a person that can be convinced? ...:):):)I think your suggestions and opinions won’t have any credibility here if you are not able to provide any reasons behind your statements.
Take care:)

[StefanStavrev]

Don't you think you crossed the line ?

I told you i think it is a bad wire and that is not a way i work, and you made a whole thread of that...

You have a brain right? Use it and do what you think it is best then ...

[Emil3d]

What line?
You started advising that this kind of topology is a bad wire and should be avoided without providing a single reason for that. You contradicted my first post here - again without giving a single reason as to why. When I asked you for any reasons behind your statements, through the course of this thread you have given only three reasons.



it is bad because will cause bad reflections
it is bad because texturing will not be easy
it is bad because that is not a way StefanStavrev works (posted in your last message)
I only respect your third reason and would never question it leaving to myself and anybody else to decide on our own if it is compelling enough to follow your advice.
However I strongly object the first 2 reasons and consider them invalid. For which I posted a detailed explanations that I believe prove this and nobody, including you, had questioned their validity.

I consider your behavior so far here as irresponsible. When you give advice to people, if you want to be respected, you should be able to state the reasons for that when questioned. Instead of that you choose to repeat like a broken record “it is awful wire” and nothing else all the time.

No smiley for you this time.

[StefanStavrev]

All those things i said are true : 1. Texturing becomes more difficult and time-loosing process

2. Reflections are incorrect

If you don't think so , i am sorry...

Have a nice day :)

PS : If you are so good at modeling and advising people, ... Can you show us your models ?

[Emil3d]

You are still stating that this is what is happening to you and not a single reason or explanation given at all.

There are many other reasons including lack of knowledge and proper workflow that may cause these problems. You have to give reasons or prove that it is the wire.

Earlier in this thread I posted this. See I’m very easy and will change my mind instantly admitting that you are right and I was wrong if you give me a simple proof. Just create and upload a scene with a textured subdivision object receiving reflections which demonstrates problems with reflections or any shading problems that are result of the conversion to polygons with the adaptive option. I will not only change my mind but I will be also very grateful to you for helping me learn new things.

[StefanStavrev]

Ok man, let's say you are right...

Show your models ...

[Emil3d]

Show your models ...
You got to pay dearly for that. They are not free.:deal:

[StefanStavrev]

Show your models - i said... Images

PS : I beleive you got none , or not worthy to show so stop playing smart ...

[leif3d]

Sorry man .You did not convinced me :)

I still think that wire is awfull.

You may have misread the rules of posting StefanStavrev:shrug: ..they are as follows...

Before posting, please review the following:


Be courteous and polite. Show respect to the opinions and feelings of others. Use of the forums is a privilege, not a right.
Engage your brain before your mouth. You are responsible for your own words and any harm they may cause.
Don't dilute the forums with irrelevant and unnecessary fluff. CGTalk is a professional, moderated forum. It's a place to talk about all things related to computer graphics.
Critiques and responses to images are to be constructive and related to improving the quality of the artwork.
I understand you are trying to help others and it's really appreciated:) , but your comments are very rude sometimes and do not encourage the person thats making the thread to better him/herself. Please be courtious to others and post constructive criticism.:)

[StefanStavrev]

My comments are rude ???

Like ???

[Emil3d]

Stefan, You should have made this kind of posting at the beginning of this thread and I would have stopped right there.

I strongly believe that you should start with posts like that, instead of exposing yourself at the end of the threads, it will make clear at the beginning what people can expect before engaging in conversations with you

Bye bye

[lollygag]

This Thread gets http://lollys.org/5stars.gif.. Front Page !!!

[StefanStavrev]

Emil3d

Words are cheap man. Show your work .

That is what people respect . Words are cheap.

In future before starting with giving lessons to others , please check your portfolio...

[Emil3d]

One last advice: Never talk to anybody in these forums before they show to you their models. That will be very helpful to all of us.

[StefanStavrev]

You keep playing smart with words, but i see no work from you...

Now if you excuse me , i don't have time for this. :)

[Emil3d]

I would like to apologies to Maunil, the original poster, for my part of taking over his thread and pushing it in a direction that he may have not expected. But I can assure that such cases are rather exceptions here:)

[StefanStavrev]

Emil3d ... That is why people think before posting ...

Let this be a lesson for future...

[anopheles]

Emil3d ... That is why people think before posting ...

Let this be a lesson for future...
you guys just have too much of what people have not enough ... something whats called time ...

[StefanStavrev]

anopheles (member.php?u=49345)

I was working while browsing this forum ... :)

[ThomasMahler]

Guys, who cares? In the end... if it looks okay and it fits the production, it's okay and will be used. Are my models good enough to prove that theory? I don't think that those cars were modeled as efficiently as they could've been modeled, but they'd still make good renders, so why bothering?

I've seen wires from productions that were far worse and they still have been used. I've seen some freakingly weird techniques being used and it still was okay. In the end... if you have to cheat, cheat! If you can get away with it, then that's just great. There's enough technical crap that we have to deal with out there anyway - So the last thing I'd bother with is if something is 'technically correct'. Those cars will probably never deform, so you can be way more forgiving here.

And yeah, Stefan, your comments have been quite rude. You could've either heleped the discussion by posting something helpful or kept out of it at all. If you feel that you've gathered enough knowledge, so that people could actually learn from you, then feel free to share it with others. We're all learning from one another and if we're just like 'Uh, that's crap!' without having the 'manners' to tell someone why the work isn't as good as it should/could be, we should just shut our mouths instead. Emil has offered you numerous times to add to the discussion - but instead you chose to tell him that the work he posted is crap without even telling him why. Way uncool, man.

[StefanStavrev]

Hey Thomas :)

I apreciate your opinion on this topic ... I keep my opinion that that was a bad wire...

PS : Sorry if that was understood as offence.It was tottaly the oposite.Trying to help :)

In the beginning lot of people have told me my wire sucks.But i kept getting better.That is just the way it is :)

Peace :)

[lollygag]

Guys, who cares? In the end... if it looks okay and it fits the production, it's okay and will be used. Are my models good enough to prove that theory? I don't think that those cars were modeled as efficiently as they could've been modeled, but they'd still make good renders, so why bothering?

Dont tell em that.. they'll stop fightin and its fun watchin/readin em.. lol

[sacslacker]

Hey Thomas :)

I apreciate your opinion on this topic ... I keep my opinion that that was a bad wire...

PS : Sorry if that was understood as offence.It was tottaly the oposite.Trying to help :)

In the beginning lot of people have told me my wire sucks.But i kept getting better.That is just the way it is :)

Peace :)

In the future, note the difference between constructive critizism and being rude. Saying something sucks without providing any guidance what-so-ever is not only rude but a waste of time.

I'd also agree that if you have to cheat, cheat. I'm sure we've all looked back on projects we've done previously and grimmaced. Eh?

[maunilpatel]

Model is alreay complete so I can't do anything now, but I will sure keep these things in mind in my next model.. thanks for all help..
Below are some rendered images..

http://img233.imageshack.us/img233/1747/ferrari3601jy3.png
http://img53.imageshack.us/img53/5093/ferrari360he4.png
http://img55.imageshack.us/img55/4556/ferrari3602xk4.png
http://img208.imageshack.us/img208/1587/ferrari3603os9.png

[de_tomato]

Thats a good render. I would like to see another render with environment.


OT:
@Stefan, can you see the bad wires now? Why the wires are so important when the car wasnt suppose to be deformable? Probly its only a still.

More over, the manners such as "the wire looks aweful, its suck! Thats not the way how I work, and peoples love my work. You can ask the pro!", arent that a bit egomaniac? Here I can say that your attitude are aweful and suck! Thats not how I am, and peoples love me, you can ask them".

Please be constructive. You were asking for Emil for images, but why didnt you? and point out whats a good modeling and whats not. There are more than one way to model, what works for you might not work for other.

[JWRodegher]

Allow me to say that the 2nd from the last 4 pictures actually show some artifacts and strange little things (not that big though) that kinda bothers the render it self. I do think that even in no deformable objects the flow of the surface should make sense or be a little cleaner that the one this car presents.

To the original poster, I will look for some pics I got of wireframes where the lines make more sense, so I can show what the advantages of a clean mesh are. I do think that if it looks good on the render that is all that matters, but it actually show some minor artifacts (which when you get some reflection will be even more visible). The polygon flow become important whenever if affects (negativelly) the surface. So maybe you could be a little more carefull. It would be enough learning a better way to convert to polys from the subds! Good luck with it man!

[Kabab]

If you want truely high qauility car bodies the only way to go is Nurbs. No other method will give you results anywhere near as good..

But its all horses for courses really..

[maunilpatel]

Allow me to say that the 2nd from the last 4 pictures actually show some artifacts and strange little things (not that big though) that kinda bothers the render it self. I do think that even in no deformable objects the flow of the surface should make sense or be a little cleaner that the one this car presents.

To the original poster, I will look for some pics I got of wireframes where the lines make more sense, so I can show what the advantages of a clean mesh are. I do think that if it looks good on the render that is all that matters, but it actually show some minor artifacts (which when you get some reflection will be even more visible). The polygon flow become important whenever if affects (negativelly) the surface. So maybe you could be a little more carefull. It would be enough learning a better way to convert to polys from the subds! Good luck with it man!

Please do so as soon as possible..
Thanks..

[maunilpatel]

again I am having the similar problem when detach the nurb surface.
the detached surface has wierd black shading on it.. This happens as soon as I detach any surface or extract polygon..


http://img81.imageshack.us/img81/7614/tempmh9.jpg

but if I select the detached surface. It looks fine, but when unselected, it looks wierd..
http://img214.imageshack.us/img214/6126/temp2dj3.jpg

[Kabab]

Log into the support site and log a support call..

Its the best way to get bugs logged and fixed.

[maunilpatel]

Log into the support site and log a support call..

Its the best way to get bugs logged and fixed.

actually it's the problem in my graphic card.. It's outdated.. so will have to deal with it until get new one, someday..

[manditri]

Put a lid on this guy - Stefan....he has been saying things without actually supporting it. U probably said "its awfull wire" some 5-6 times on the first page of this thread. And if u r giving advice to a beginner then thats pretty disheartening.

What he is saying about the wires has importance in character modelling
(deformations, reflections, texture stretching, skinning). Actually the problems arise only from deformations which can cause skewed reflections and texture stretching due to bad skinning and wires. And it also matters if the rendered product is in polys. Bcuz the facetedness of polys can affect reflections.

But here the final rendered image will be in sub-div. And this is an object model so no deformation. Once u convert it to sub-div and surfaces look good without any uneven bumps and stuff, ur model is just fine. The reflections will be fine too since this is a subdiv object. The only problem that might arise from unevenly spaced wires is if u use some 2D procedural texture(noise or something) but that can only occur if ur edges have one vert in tokyo and the other in timbuktu.

Hope this helps. and btw great model maunil. lets see it rendered.

[maunilpatel]

Put a lid on this guy - Stefan....he has been saying things without actually supporting it. U probably said "its awfull wire" some 5-6 times on the first page of this thread. And if u r giving advice to a beginner then thats pretty disheartening.

What he is saying about the wires has importance in character modelling
(deformations, reflections, texture stretching, skinning). Actually the problems arise only from deformations which can cause skewed reflections and texture stretching due to bad skinning and wires. And it also matters if the rendered product is in polys. Bcuz the facetedness of polys can affect reflections.

But here the final rendered image will be in sub-div. And this is an object model so no deformation. Once u convert it to sub-div and surfaces look good without any uneven bumps and stuff, ur model is just fine. The reflections will be fine too since this is a subdiv object. The only problem that might arise from unevenly spaced wires is if u use some 2D procedural texture(noise or something) but that can only occur if ur edges have one vert in tokyo and the other in timbuktu.

Hope this helps. and btw great model maunil. lets see it rendered.

Thanks for help
Rendered image for car is in post# 50

[earlyworm]

Just to comment on the black faces showing up...

If you have 'two-sided lighting' off (in the lighting menu, top of the persp window) and the normals are pointing in the wrong direction then your faces will go black - a handy way to check if your normals are all correct without toggling backface culling on and off trying to spot the flickering.

And some comments on the wireframe...

One, this is going to be tricky to modify, for yourself and for anyone else who may need to edit or change the model.

I did notice some artifacts in the render from the mesh... may seem no biggy, but I know I'd get asked to fixed those. Then again I've never been asked to model a car so what do I know.

http://www.earlyworm.co.nz/3D/images/mesh_render_probs.jpg

[maunilpatel]

Just to comment on the black faces showing up...

If you have 'two-sided lighting' off (in the lighting menu, top of the persp window) and the normals are pointing in the wrong direction then your faces will go black - a handy way to check if your normals are all correct without toggling backface culling on and off trying to spot the flickering.

And some comments on the wireframe...

One, this is going to be tricky to modify, for yourself and for anyone else who may need to edit or change the model.

I did notice some artifacts in the render from the mesh... may seem no biggy, but I know I'd get asked to fixed those. Then again I've never been asked to model a car so what do I know.

http://www.earlyworm.co.nz/3D/images/mesh_render_probs.jpg

This is just a bigining for me, this is roughly my third model ever, and this is not project, it's just I was building it for fun using some tuto. Since I know about what can go wrong, I will be careful in my next model. I don't have deep knowledge in modeling, but anyways, you learn it from experience. Next time when I convert subds to Polygon, I will be try to be as much careful possible..
Thanks for all help.

[zmip]

If you want truely high qauility car bodies the only way to go is Nurbs. No other method will give you results anywhere near as good.

Now it's my turn to step in and disagree. One absolute master of carbody polygon topology is this guy "The Shaddix", as seen in his work at: http://www.cg-cars.com/forum/showthread.php?t=3 (lots of images seem to be missing, skip to page 34 to see some awesome pix, I also take the courtesy to post one of his excellent wires here). (uploading images seems to be impossible on a Mac, neither with Safari, nor with Firefox...) http://pimz.com/download/wire3.jpg

[lricho]

if you are only wanting to render the car, then fine, polys, subdiv, nurbs... whatever you're comfortable with that gives a good result.

however, i think car designers and manufacturers would disagree and say that only nurbs are acceptable, since those models need to be spot on precise for machining. Happy to be proved wrong since i'm not a car designer, but my brother is and we've discussed this sort of thing fairly indepth in the past.

[Smithjoe1]

StefanStavrev (member.php?u=232684), all you have done here is outline to everyone how much of a tool you are. Instead of saying it was a bad wire, you should have said where the problems were, an example of where it was well done into your opinion, and what he could have done to fix it, instead you decided to stay on your highstool and just said it was a bad wire. Perhaps next time you can decide to be helpful and sugest ways to fix the problems, or provide examples instead of just insulting his work.

maunilpatel, nice job on the car, a few small artifacts that other people have already outlined, I'd love to see it with an environment to show off its true reflective quality, just something simple for it to reflect.

[JamSession]

First of all, modeling is something you learn from experience. In a year or two come back to this model and look at it. You will see some things that you like, and some things that will make you say WTF was I thinking.

As for the wire, For hard surfaces such as cars, houses, the wire isn't too important. Where it is important is when it is organic and will need to be rigged and animated with good deformation. That is the big reason behind good topology, it means better deformations.

With cars and other hard surfaces you need to be careful if you are on a timeline because of render times. If you have no deadline and it isn't going to be animated then play around and see what works and what doesn't.

No matter what you do, someone will always bash it. Look at Pixar and ILM, people still bash Pirates of the Caribbean II and Cars and they are the best there is. so don't get mad, take it as constructive critisism and make yourself better.

[Kabab]

Now it's my turn to step in and disagree. One absolute master of carbody polygon topology is this guy "The Shaddix", as seen in his work at: http://www.cg-cars.com/forum/showthread.php?t=3 (lots of images seem to be missing, skip to page 34 to see some awesome pix, I also take the courtesy to post one of his excellent wires here). (uploading images seems to be impossible on a Mac, neither with Safari, nor with Firefox...) http://pimz.com/download/wire3.jpg
Those models are fantastic the guy is very talented..

But for turely godly cars nurbs are they way.. Yes it's harder yes it's more time consuming but it will truely give you the highest quaility surface.

Let me give you a screen shot of a nice nurbs car model..

[Kabab]

Now to be fair you don't have enough tools in Maya to create surfaces of this qualilty..

And this level of surface is pretty much over kill for VFX, the only places i can think this would be used is in car comercials with slow closes up's or for billboard type renderings.

*These are not my models they are from Alias.

[lricho]

And this level of surface is pretty much over kill for VFX, the only places i can think this would be used is in car comercials with slow closes up's or for billboard type renderings.


How about precision machining of surfaces for real-world, lifesize car models? Alias didnt make studiotools simply to make big billboard renders. :)

[Kabab]

How about precision machining of surfaces for real-world, lifesize car models? Alias didnt make studiotools simply to make big billboard renders. :)
Yes well i'm well aware of what studiotools is used for (alias certified trainer :) )

I was just speaking in a VFX context :)

[lricho]

Yes well i'm well aware of what studiotools is used for (alias certified trainer :) )

I was just speaking in a VFX context :)

damn. Thats one up on me (brother of car designer (ford), so thinks he knows more about the subject than what he does).

I'd also be pressed to think of any other uses for that level of surface detail in purely VFX related arena's. Mebbe if you were outputting for IMAX 3D?

[Kabab]

damn. Thats one up on me (brother of car designer (ford), so thinks he knows more about the subject than what he does).

I'd also be pressed to think of any other uses for that level of surface detail in purely VFX related arena's. Mebbe if you were outputting for IMAX 3D?
Haha i'm sure your brother knows his shit it ain't easy getting a job as a car designer :)

I do know that for a lot of car comercials these days the manufacture supplies CAD data to the production company that is doing the comercial..

Mind you Nurbs in general has good advantages small footprint as its all defined from formula's not discreet vertex locations(those models i posted would be huge when converted to poly's)..

Inherit UV's..

Resolution independant so no matter what resolution you render at you can always get a smooth surface.

[lricho]

Haha i'm sure your brother knows his shit it ain't easy getting a job as a car designer :)

Oh, i know he does... dunno if it came across as me saying *I'm* the one who thinks i know more than i do (i say at the risk of looking somewhat repetitive and foolish)


I do know that for a lot of car comercials these days the manufacture supplies CAD data to the production company that is doing the comercial..

good common sense and use of resources. I was actually wondering how many manufacturers would do that. Be silly not to, of course, but you never know how precious companies are about their assets.

[Kabab]

good common sense and use of resources. I was actually wondering how many manufacturers would do that. Be silly not to, of course, but you never know how precious companies are about their assets.
I know Toyota does this... Holden has a massive internal visulisation team..

[zmip]

however, i think car designers and manufacturers would disagree and say that only nurbs are acceptable, since those models need to be spot on precise for machining.

Sure, for machining you need your data in a different format (NURBS), but does that make it a *better* surface? I designed and created several cars for Pioneer's In Car Entertainment Guide last year (www.pimz.com), built them entirely from NURBS surfaces. It was quite a challenge in Maya. Looked a lot at StudioTools tutorials and although ST is of course inherently better suited for this sort of modeling than Maya, the endresult isn't much different. NURBS are nice, but extremely limiting when it comes to quickly defining freeform shapes. StudioTools hides much of the mess from you, that's why those wires look so slick and simple (which is not a negative thing, actually quite the opposite).
As for visualisation goes: well, in 99% of the cases you think you're looking at a NURBS surface, you're actually seeing a polygon approximation, so true in the viewports as well. The only renderer I heard of that really renders NURBS is RenderMan, but there are probably some others too.
So since I've come to realize that it's polys most renderers need, and it takes a lot of effort to adjust the tesselation on NURBS surfaces for hi-res rendering (automatic calculation is not a serious option), I'm not so convinced that NURBS are *the way to go* when it comes to making slick carbodies (for visualization purposes, agreed). If you're already spending a lot of time adjusting tesselation, you might as well convert to polys in the same step (it's the same thing, basically).
Another point is that with NURBS, you're building cages to flow your surfaces. With Polygon Smooth, exactly what is the difference? None whatsoever (sure, there's slightly different results in curvature, they don't match 1:1, but that's not my point), and the resolution is pretty much endless too. If current CAM systems don't cope with polygons, but only with NURBS, wouldn't that just be a limitation of those systems then, not the evidence that NURBS are better suited per se?
Another supposed "pro" for NURBS is implicit UVs. Well, I may be a noob in NURBS afterall, because I can't remember ever having the parametrization of my NURBS surfaces to be actually suitable for texture mapping. It's nowhere near as flexible as the explicit UV mapping of polygons.
Hmmm... I look like a NURBS basher here ;-)

[Kabab]

I still think you will get higher quaility from nurbs because of the workflow..

Laying out curve's checking the curverature comb making sure transitions are smooth you just can't do this with poly's or Maya for that fact.. I'd love to be able to plot a curvature comb through a sub D poly model and see what it looks like (i bet fairly average)..

The ability to cut out perfect circles from surfaces with trims.. The ability to being able to specify a radius dimension eg 1.25mm..

The reason those wires looks sick is not because studio is hidding anything its because they are actually well built that is a Class A surface it doesn't get better then that.

I do agree but poly's are superfast for freeform stuff there is no two ways about it but i still don't think they hold the same quaility.

MR and renderman both do good jobs or rendering Nurbs thats basiclly the entire highend rendering market...

The reason poly's will never take off in the cad/cam world is not the machining many programs can machine from poly's, its because solid modeling products like CATIA, Pro / E etc can don't jack with poly's.. With nurbs you can use all the solid modeling tools on them and other tools..

I personally tihnk both methods are great and people should learn both and use what works best for the situation.

[zmip]

Laying out curve's checking the curverature comb
Speaking of which, was I dreaming, or was there an option to see the curvature comb in Maya?

The ability to cut out perfect circles from surfaces with trims...
Only to find out later that those trims are the worst to render smoothly, because of tesselation that happens before rendering. Besides that, editing the resulting trimcurves shows what a total mess NURBS modeling sometimes becomes (huge amounts of CVs, uncontrollable). This may be Maya, but I doubt it. It's the kind of thing I think StudioTools is hiding from you. Judging from the tutorials I've seen, it all looks simple and sleek, where in Maya, you get to see (and work with) the raw deal, which can be frustrating at times.


The reason those wires looks slick is not because studio is hidding anything its because they are actually well built that is a Class A surface it doesn't get better then that.
Can you see the resulting CVs on a trim curve in StudioTools? I can imagine you can, but StudioTools seems to tuck that kind of access far away and only shows you easy-to-work-with controls (exactly how it should be, don't get me wrong). In Maya, NURBS modeling is much more basic, for the obvious reason that they don't want Maya eating into the marketshare of ST.

MR and renderman both do good jobs or rendering Nurbs thats basiclly the entire highend rendering market...
Which version of Mental Ray are you referring to? Last time I checked (v3.4), MR doesn't render NURBS directly. There would be no need for setting tesselation if MR would do so. All NURBS surfaces get converted to polys at rendertime.

[Kabab]

Nah no comb in Maya :(

You can render trimed edges ok just turn on smooth edges for the trimed surfaces...

The approximation editor with parametric setting does a good jobs of nurbs in MR

In ST you can see all the extra ep generated from a trim..

[maunilpatel]

How about SubD
wouldn't they render smoother then Nurbs? or if you have to choose from Poly(smooth) or SubD, what would you guys choose?

[Kabab]

In theory they should render out smooth..

The thing with nurbs is you can control a large complex surface with 2 degree 3 curves..

The less points you have to play with the higher the tension of the surface which results in smooth more gradual curves...

With poly's you can quickly end up with to many points..

[zmip]

How about SubD
wouldn't they render smoother then Nurbs? or if you have to choose from Poly(smooth) or SubD, what would you guys choose?
Personally, I favor Poly-Smooth over SubD. I think SubD is on its way out (I read that Stahlberg is solely into Poly-Smooth these days). One of the big advantages of Poly-Smooth is that you can keep a relatively simple 'cage' without different 'levels' you have to maintain.

If I were to build a car model these days, just for visualization, I think I'd use NURBS for the main panels, then convert those to relatively rough poly meshes and work with Poly-Smooth for further detailing. Keep in mind that Poly-smooth can offer you the same infinite resolution that NURBS can.

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