Trouble with Subd's (photo attached)

# 1 27-07-2008 , 07:36 AM

Subscriber
Join Date: Feb 2008

Location: Arizona

Posts: 30

After converting poly to subd, my surface looks as though there is some other surface poking through, like a sandbar poking through a calm watery surface. It's a very subtle "island" effect though and I can adjust the edges or vertex and push/pull the sub surface up or down but it is awfully difficult to maintain symmetry.

For example, I am modeling the fender of a car and after converting to subd's, I have refined the area around the scoop and it looks terrific. However, after applying a coat of paint to the hood, that second subsurface (sandbar) can be seen very easily. I can push that surface down below the paint but other areas of the hood begin to show the same effect.

Even after I use the Render the Current Frame command, the effect is even more noticeable.

How do I correct this?
user added image

TIA

Quote

# 2 27-07-2008 , 03:33 PM

Subscriber
Join Date: Sep 2007

Location: Mississauga, Ontario, Canada

Posts: 450

I can only imagine that it is due to messed up normals or odd modeling. Are you going from nurbs to SubDs or polys?
If you are modeling in Polys if you hit your number 1, 2 or 3 keys you can vide different levels of subdivision preview before converting. Switching back to 1 will give you your poly model and you should be able to use these switches to find out what is causing you so much grief.

If your normals are messed up you might get this, but I can only think that some messed up models converted to subds would give you this issue. Make sure your mesh is nice and clean before converting.
Cheers.

Peace, love and Anarchy~~~~~~~
______________________________
Wip:
iMac
Full House Project
Arch Viz Reel

My Website is Finally Back up!

“Welcome to the Internet. Where the men are men, the women are men, and the children are FBI agents.”

Quote

# 3 28-07-2008 , 09:20 AM

Subscriber
Join Date: Feb 2008

Location: Arizona

Posts: 30

Thanks AH.

I screwed up.

Somewhere along the way, I inadvertently created a duplicate without realizing it. So I had two items, one of which was converted to subd. I didn't realize it until I examined the Outliner. I can't be certain but I'm sure this occurred from having not stepped back far enough through my Undos.

When I clicked the Plus-sign box beside the item in the Outliner, I found two poly items with the word "history" in the filename and numbered 1 and 2, along with the subdTessShape1. I deleted the second poly item and the look of my surface cleared right up.

The hardest thing to overcome is not fully understanding the Maya naming convention and if I'm not careful to name everything as it's created, I have no clue what it is later on.

Believe it or not, I like making mistakes like this, even though I spent several hours trying to resolve it, because it only enhances my learning experience.

Quote

# 4 06-08-2008 , 01:08 AM

Registered User
Join Date: Jan 2005

Location: vienna

Posts: 1,095

it´s not too hard tho to understand things like that. just get used to make use of diagnostic tools. this problem of you often happens when converting some 1000+ polys to subdiv and the back to poly but not via modify but using the undo operation. sometimes maya is confused then and outputs both versions - subDiv + poly connected to each other.

in hypergraph you can see this clearly, just delete one of the versions you don´t need, subDiv or poly - I guess it´s subDiv.

PS: you can´t just delete this connection of shapes the normal way.

diagnostic tools:

hypergraph is your friend - ScriptEditor also ofc, Hypershade is interesting too sometimes, not just for shaders.

btw - if your mesh isn´t clean like nonmanifold geo or non uniform normals and stuff like that, maya dosn´t let you convert the geometry at all.

everything starts and ends in the right place at the right time.

Last edited by Falott; 06-08-2008 at 01:14 AM.

Quote