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thomastorfs
09-02-2006, 08:26 PM
Hi,

I'm quite new to this forum and to modelling. I tried my best not to bother any of you by searching and learning independantly as much as I could. But I kinda ran into an unsolvable problem. At least, to me it is.

The problem is pinching by the edge tension when meshsmoothing. But in order to keep the model correct and separated into quads, the edges causing the tension are needed. I tried removing them, lowering vertex weight, moving their position to soften it, etc..

Can't find a way. Does anyone know how to solve this?


Thanks in advance!




Thomas

mike0006
09-03-2006, 02:46 AM
Well, I'm not really sure that you're talking about with the pinching. Explain a little more clearly what you are talking about. Maybe draw a line over where it is? Everything looks like its running pretty well. Also, mabey a reference pic of what you are trying to achieve.

thomastorfs
09-03-2006, 11:20 AM
Hi, thanks for the reply. Here it goes.

To round the bumper part's edges (see blue lines in wireframe) and still keep the quads, I think I have no other choice than to extend it vertically by cutting a vertical edge (red lines). This creates a kind of a very broad chamfer; which in its turn, creates more tension on the edges and thereby creates a very subtle corner when meshsmoothing. I added a bit more specular level on the material to give it more noticable contrast.

Any ideas how to get rid of that?

mzee
09-03-2006, 11:33 AM
i think you have to do something like this but i'm not quite sure if this is what you want.

cheers,

mzee

thomastorfs
09-03-2006, 12:36 PM
Hi Mzee, thanks for your reply. I tried your suggestion, but it didn't solve the problem. Altough, I think modelling the bumper that way would be a good idea when I model the next car.

The problem here is that there is a very minimal vertical corner, caused by the "wide vertical chamfer" starting from the edges of the bumper towards the top and the bottom. I searched that famous modelling thread over here (http://forums.cgsociety.org/showthread.php?t=40373) , unfortunately without any solutions.

I added a full model render. Any idea how to remove that slight corner near the front bumper? (I know there are more minor issues with the model, but that's for later :) )


cheers,

Thomas

mzee
09-03-2006, 12:53 PM
hi!

Can you post some closeups of the area that causes the problem?

Its hard to see the problem.

cheers,

mzee

thomastorfs
09-03-2006, 01:14 PM
There you go. I painted some lines to emphasize the corner.

thomastorfs
09-03-2006, 01:40 PM
I think I may have found it. And the solution is actually quite simple; adding more geometry to round it better. While browsing the forums I stumbled upon a guy named Ali Ismail who created some photorealistic car renders. He had a similar car front. Check it out.

http://www.aliismail.com/gallery/wires600.jpg
http://www.aliismail.com/wip/s600wiref.jpg


Now here's a big one: How remove that corner and keep the polycount? :)


cheers,

Thomas

mzee
09-03-2006, 01:49 PM
I think the greenline is causing some problems.
The reason for this is that the distance(yellow lines) to the right edges are really small in comparise to the left edges.
==> You got an mesh-emphasise to the right side.

thomastorfs
09-03-2006, 01:55 PM
aah yes, that's how it's called :) I'm not yet that familiar with all the correct terms. So, you're saying there is no solution to that exept to add geometry? (as the vertical edges are needed to keep quads when rounding the corners of the bumper)

mzee
09-03-2006, 02:02 PM
I don't think its really called so - that was the only word that i thought a the moment.
Adding more edge is one possibilty but not ever the best one.
==> Could cause more problems

I think you should try to get nearly the same distance between the left and right edge - so the mesh density is everywhere the same.
You see what i mean if you smooth the geometry and take a look at the mesh. on the right side the spaces between the single edge are much smaller than on the left side

Hope this explanation is comprehensible

thomastorfs
09-03-2006, 02:19 PM
Yes yes, I understand you perfectly. I did so before. But as you can see, the corners of that bumper are actually even meant to be even sharper than they are now. So spreading the edges out is not really an option. Maybe redefining the loops could do the trick.

Have to go now. Have an appointment. catch up with you later. Thanks a lot for your help! :)



cheers,

Thomas

FastForward
09-03-2006, 06:44 PM
I had the same problem when I modeled my first car , and after hours of trials and errors, I finally detached that part of the bumper as a new object, since the crease was deep enough. OK, it's cheating, but if you're going for a still, why not ?

thomastorfs
09-03-2006, 10:45 PM
Hi FastForward, thanks for dropping by. Hmm, interesting technique. I'll give it a try tomorrow. You say it should do no harm when going for a still, but what are the disadvantages when wanting to create a movieclip instead?


cheers,

Thomas

thomastorfs
09-09-2006, 12:59 PM
Right,

I tried that technique but it was no use for the goal I was aiming for. I'll make you guys a deal: whoever helps me finish this model gets it when it's finished.

The bumper is coming along nicely but I've got a pinching problem at the sides, which is strange for quads. Anyone got a solution to this?



greets,

Thomas

4 low
09-09-2006, 09:57 PM
Might see if adding a few cuts like this helps any:

http://img242.imageshack.us/img242/2853/picnu3.jpg (http://imageshack.us)


Maybe it'll help...

thomastorfs
09-09-2006, 11:22 PM
Hi 4low, thanks for dropping by. Tried your suggestion, and it lead to this result.


EDIT: and as I'm a man of my word, I also include the MAX file for what I have now.

thomastorfs
09-11-2006, 12:06 PM
2 downloads of the model. I'd highly appreciate if anyone is downloading the MAX file, he or she at least tries to help me out.

Anyone got a solution to this pinching problem?

Singularity
09-12-2006, 04:29 AM
One more download, but I haven't got an answer for you yet. Been away from max for ages.

I think you need to have an edge extending diagonaly away from the corner to suport it, rather than the two at 90 degrees you currently have.

Singularity
09-12-2006, 05:15 AM
3DPalace's free Audi tutorial models that exact bit. Its in vid #9 - front detail. So take a look. He supports the corner with a diagonal through that pinch.
3D Palace (http://www.3d-palace.com/index.php?option=com_frontpage&Itemid=1)

Rookz
09-13-2006, 09:18 AM
i'll have a look for you tomorrow after i get off work, i used to have exact same problem when i was just starting out

thomastorfs
09-13-2006, 09:54 AM
Hi Singularity, Rookz,

Thanks a lot for the input.

Singularity, I started out with that tutorial, but since I found him modelling not accurate enough when going into details, I went my own way. I tried that technique of cutting an edge in the directions of the pinching problems, but without any result. The only thing that has improved the model to date was to create extra geometry.

Rookz, now you're making me curious :) Hope to hear from you soon.


Meanwhile, here's an update. Did some editing with the help from Rook at Threedy. It's still not solved, rather been softened. And it created extra problems towards the open cut.


cya later,

Thomas

Rookz
09-13-2006, 09:28 PM
well i took a look, that area seems fine to me

maybe i'm missing something?

by the way, i'm Rook from threedy, but since that was taken here i had to improvise a little :)

Singularity
09-14-2006, 02:36 AM
Looks OK, to me too.

Don't you hate having to re-invent your name.
One forum, I've had four over ten years as they've upgraded etc.
Had one guy tell me in a post, that he thought another poster rude (me in earlier name) and he ranked as helpfull but absent me again by my first name. He had no idea all three were the same guy and I seemed to have hit the heights and depths of his estimation over a year or so. LOL

thomastorfs
09-14-2006, 06:13 AM
hehe, I had that slight idea you were Rook. Here's a pic to make it a bit more visible.

Rookz
09-15-2006, 04:29 AM
ok, thats because polies there should be as close to perfect rectangles as possible, there's really no work around it, not that i know of, its just the way you placed your polies, i dont have that problem with my model because i dont have any uneven polies in problem areas such as this

diginime
09-21-2006, 08:30 AM
Hi there, is it the vertex problem? I'm also modeling Audi A3. Maybe you can move the vertex around? Below is mine. If i had wrong please correct me. Thanks.


http://img98.imageshack.us/img98/5067/regiontf2.jpg

http://img97.imageshack.us/img97/712/regionuv1.jpg

Rookz
09-21-2006, 07:54 PM
ok, well i was a little hesitant to post this, but whatever, if you dont like it, you know where the Delete key is :D

also if you do use it, let me know, i wanna see what you come up with

and since i cant attach the blueprints i used (too large) i've uploaded them to imageshack
save them to the same folder you'll be unzipping .max file to

http://img49.imageshack.us/img49/9168/frontvq0.th.jpg (http://img49.imageshack.us/my.php?image=frontvq0.jpg)

http://img84.imageshack.us/img84/9950/backxx5.th.jpg (http://img84.imageshack.us/my.php?image=backxx5.jpg)

http://img49.imageshack.us/img49/9960/sideba4.th.jpg (http://img49.imageshack.us/my.php?image=sideba4.jpg)

http://img84.imageshack.us/img84/8871/topwx7.th.jpg (http://img84.imageshack.us/my.php?image=topwx7.jpg)

thomastorfs
09-24-2006, 04:50 PM
Hi Rookz, diginime,

Thanks for keeping posting. :) I'm updating my portfolio right now. Programming stuff etc. Once that's finished, one of the next days, I'll get back on it and share the results.


cya later,

Thomas

thomastorfs
09-29-2006, 03:12 AM
Hi Rook,

Quickly dropping by to say I had a look at your model. I must say it looks fantastic :) Thanks a lot for posting it. It'll help a lot!

Until this moment, I still haven't had time to work any further on it. Anyway, like I said, I'll keep you posted once there are any updates.



cya later,

Thomas

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