NURBS 350Z update (paint render added)

[dilbert1]

My computer took a dump on me so I've been out of action for a few weeks. I'm determined to actually finish a project for a change, so I'm still trucking along with the Nissan. I'm not happy with a lot of stuff, but it's been a great learning experience tackling this project. I think I've tried every Maya trick in the book with this car, so if anyone has any questions on what tools seemed to work well and which ones didn't, maybe I can save another Maya user from the pitfalls I encountered.

[f50]

That's looking great, man
I've had a try or 2 at doing NURBS modeling myself, and I'm quite impressed that you've wrestled a 350Z out of them.
Any chance we can see some wireframe shots of the surfaces? and maybe your guide curves?

[aink]

Nice work, have some tutorials for that?

[killerskull]

Yea looks really nice. Keep up the work

[dilbert1]

Been working on the wheel. Aink, I'd love to help out if I can, do you have any specific questions? Unfortunately my job (military) prevents me from working on a full-on tutorial, but maybe I could help out with some specific things. There's some awesome artists on this site who have already written some great tutorials, but I found that none were in Maya, and 90% were poly modeling. Maya is a little tricky with NURBS, but I think they can give a smoother finish in the end. Check out Seiyusha's VW beetle concept car a few pages back, which is all Maya NURBS.

[aink]

yeah thanks I'll check that. Like u said, there's only a few maya car NURBS modelling tuts, ATM I have no specific question since I'm not tried Maya yet, but I have plan for that when I have time.
thanks

regards

aink

[ML]

lovely model!! you also just happened to make the set of rims that i would prefer on my 350z instead of the 6 spoked ones

[dilbert1]

Finished the tires. The renders are quickies, so they're a little jaggy

[TheGoog]

I'm loving how the car is turning out man. Very smooth, and look very accurate so far.

I have a few question though. Not necessarily related though. I just started an animation course and their main focus is on maya for the modeling and animating part. Now how much work is it to do a car in nrbs with maya, or would you prefer poly modeling if it just came to pure speed in modeling. I just have to start thinking about my demo reel already and I need to get an idea of what direction I'm oing to go in the modeling sense.

Also, any car centric tuts for maya that you know of would be awesome.

Also, those rims look perfect. very, very clean.

[dilbert1]

Modeling hard surfaces in NURBS is all about getting your original curves perfect. Use all the curve editing tools at your disposal to create tangency and continuity between curves, and tweak, tweak, tweak the curves until they look perfect. Once the curves are set up, the actual building of the surfaces is easy using either the bi-rail, square, boundary, or fillet tools. The great thing with NURBS is that you can edit the surface globally and locally, plus if you keep the construction history on, you can tweak your guide curve and it'll update the entire NURBS surface which is a BIG advantage!

Speed wise I don't know. Once you've mastered the whole NURBS tool set (which is large with many attributes within each tool) I believe NURBS would be quicker to model an object, however the learning process takes some time. Polys are very intuitive, and most people can pick up modeling quickly with them.

It also seems like you have more ways to skin a cat with NURBS (at least in Maya anyway). For instance, I know of 3 or 4 different methods of producing the break lines between panels of a car. There's the Round Tool, Freeform Fillet, Bi-rail, and direct CV manipulation. I've tried all and found that unfortunately there's no 'best' method. Each tool has it's advantages depending on the situation. However, once you've used all these tools a few time you'll soon be able to look at a modeling problem and instantly know which tool is going to give the best result.

Finally, the best Maya NURBS car tutorial I know of is at www.3dtotal.com. Go to free stuff>tutorials>maya and you'll find a 4-part tutorial for a BMW. Also I can highly recommend the Gnomon Workshop DVD called NURBS modelling of a GTP race car. This is an excellent CD for being introduced to the wealth of NURBS tools available in Maya.

Hope this helps

[Shorty]

very clean and impressing. I had a go at maya, but after i've worked 2 years with max, i dont wanna start over with something new anyways, great job !

[dilbert1]

Small update. Stuck a Nissan logo on the front, and finally did the hood indents which were a little tricky. Also rendered a Maya software render to see a few darker shadows, and a quick screen capture for a wireframe.

[SeiYuusha]

very well done !!!! man, youre getting better and better....

btw, can you post the wire from rear view ?

[killerskull]

Itll look killer after you render it

[dilbert1]

I've got a good paint shader set up, but I could use some help on a good tire rubber shader. Anyone have any ideas for one in Maya, or another software if I can translate the basic principles.

[o.j]

Looks clean as hell. The 350z is a beautiful car.

[3rd user]

really nice modeling process...i wish you had posted it from the begining.
anyhow....How did you model the part i'v marked(I'm sorry i did this,i dont want to insult your copyright)whatever i do i end up with at lease 3 pieces.and they wont match even with stiching stuff re arranging verticies,it just dont
i believe Gnomon Nurbs Modeling(3Dvds) is a great way to learn the Nurbs Modeling in Maya.
Waiting for the tip Master

[dilbert1]

Seiyuusha, I'm away from my software right now, so I can't render a rear wireframe view, however I'll do one tonight and post it. I'm going away for 4 weeks on Wednesday (military stuff) so I'm trying to finish up the modeling before that, and then I'll tackle the rendering when I get back.

Pooya, that is a tricky area to get right with any car for a number of reasons. There is two main ways to do it, I'll explain both, and I use the second method.

Method one. This is very similar to the way RainNight tackles his Audi tutorial in Lightwave on this site. First create the side of the car with no regard for the wheel-well. It should be a smooth one-piece surface that stretches the entire length of the car. Then ,using your reference pics, create and project a real nice smooth curve onto this surface to outline the wheel well. Use the trim tool to trim away the circular portion of the wheel well, which should leave you with a nice smooth surface with a perfect circular section cut out.

Next, right click on the surface and pick 'trim edge' and then select the trim edge that defines the wheel rim. Go to edit curves>duplicate surface curves default settings and hit create. Delete history on this curve and then use this curve to create duplicates that you will scale and move into position and edit to define the shape of your wheel well in your different views. The reason we duplicate the surface curve, and not just create a new one is because you want the CV's on your new guide curves to match exactly with those on the trimmed edge. Now loft or birail between the trimmed edge and these new curves. You now should have a real nice smooth wheel well with positional continuity with the trimmed edge.

To create a nice smooth tangency continuity at the edge where the wheel well meets the body, there a a few different methods. You can try the Round Tool first, but this rarely creates a good transition for this kind of geometry. Instead, create a NURBS circle and scale it down to a size where the radius looks like a good size for the transistion fillet that you want to make. Then use the Surfaces>Extrude tool to extrude this NURBS circle using the Trim edge on the body as the extrude path. This should create a pipe along the transition edge between the body and wheel arch. Next, select the pipe and go to edit NURBS> extend surfaces to extend the pipe along it's long axis a small distance past any surface it touches (this step is essential for the next step). Now, select the pipe and the car body and go to Edit Nurbs>Intersect surfaces (make sure that create curve on both surfaces is checked). Repeat but with the pipe and wheel arch selected. Now can delete the pipe and you should see two nice curves on the surfaces of the body and wheel well. Now, use the Trim tool to trim away the tiny strips between the two surfaces and you should be left with a gap between the two the size of the diameter of your original NURBS circle.

Finally, select the new Trimmed edge on both the body and wheel arch and go to Edit Nurbs>Freeform fillet, or you can use Edit Nurbs>Fillet blend. Volia, you have a nice fillet between the two surfaces that has positional and tangential continuity.

Sorry I have no pics, but I'm away from my software.

Method 2 (used in this model). This method can be frustrating as hell but ultimately gives you more control of your surface. This is identical to the way organic models such as patch modeling a human head is done. I'm gonna try to explain this quicker, and I'll post a link to a tutorial that should help.

First create ALL the guide curves that will be used on the model. Use all your curve editing tools to get as much curvature continuity beween curves that you can. Then use the bi-rail or square tool to make the surfaces. Use the square tool if possible as this has the option of producing curvature continuity which is one step above tangency continuity.

Now comes the hard part. In the specific area you asked about, you should always aim to have 4 surfaces intersecting (I had to use 5 in this model). Using three surfaces like you mentioned is going to give you no end of problems. The basic idea is to have the surfaces intersect at as close to 90 degrees as possible. Now, create a shelf that has the Attach NURBS surfaces, delete history, Detach surfaces, and rebuild surface tools on it. You'll be using these time and time again in rotation, so trust me, making a shelf will save you mucho time. Now, select two adjacent surfaces (1 and 2, see attached pic) and attach them with the blend option on, insert knot UNCHECKED, and keep originals off. Immeadiately delete history on the new surface. Next, select the isoparm that defines the join you just made and detach the sufaces. Rebuild these new surfaces to be uniform with the same number of spans that they originally had (always use uniform parameterization), and delete history. Now repeat this procedure but selecting the next two surfaces (2 and 3) in a clockwise direction. You should keep going around in a circle until the transistion between the surfaces is undetectable, and you have a star shaped gap at the intersection.

Next, go to your Edit Nurbs>Stitch>Stitch edge tool and start stitching edges with the tangency button checked. Once again, proceed in a clockwise pattern and stitch the edges until there is no hole. Chances are at this point the surface is looking smoother, but there's probably a little 'point' at where the surfaces meet. Delete history on the surfaces, rebuild surfaces, and then apply a Stitch>global stitch with normals selected as the tangency option. Look at the result. If it's not perfect, guess what, repeat whole process!!! (now you can see why you set up the shelf. If you do this for long enough, eventually you'll massage those pesky NURBS surfaces into submission, and nobody will know it is a patch model rather than one surface.

Whew!! Sorry, too much writing I know, but these methos can solve 90% of NURBS surface problems. Hop it helps.

Heres an excellent little tutorial for practice (scroll down to 'Stitching Surfaces' tutorial. You have to be a bronze member to view it, but that's free). I did this for many hours to perfect the technique, and once you've got it down it's actually pretty fast. Also, check out any tutorial in Maya for patch modeling a head and I guarantee it'll use the above technique.



http://www.alias.com/glb/eng/communi...s.jsp?start=41

[dilbert1]

Sorry, just tried that link and it doesn't take you to the correct page. Go to tutorials>Maya>Modeling then scroll through the pages until you find 'Stiching Surfaces'

[dilbert1]

Seiyuusha, managed to get to my computer real quick. Here's a couple more wires. Just got to model the brakes, windshield wipers and headlights, and then I'll move onto texturing. By the , way do you have any good tire rubber shaders?