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SLAYER
12-29-2003, 12:54 PM
Hi,
I have attached an image of a a bike frame deign in progress. I laid this out to develop a design and now that I have one, I will model this same idea, but more realistic and detailed.

This is done in regular mode (non-sub d). Most of the stuff I do is organic (sub-d) so I do not get the errors you see.

The errors are in my shadows (gaps) and the smoothing on some of the tubes. The tubes have 24 to 36 sides and I can make them smooth in modeler screwing with the smoothing threshold. Also, I have render level of 10 in my layout render options.

How can I fix these?

Thanks

toby
12-29-2003, 01:26 PM
There must be something wrong in the geometry of the tubes, especially if you're having smoothing problems too.

Can you post a picture in wireframe shade of just 1 tube?

SLAYER
12-29-2003, 02:31 PM
Originally posted by toby
There must be something wrong in the geometry of the tubes, especially if you're having smoothing problems too.

Can you post a picture in wireframe shade of just 1 tube?

Sure. HEre is the down tube simplified by itself.

SLAYER
12-29-2003, 02:33 PM
Here is that same tube rendered.

Tesselator
12-29-2003, 02:51 PM
Yup. Nonplanear or other weirdnesses like embeded polylines or such. Just use the Stats window in Poly Mode and clean it up the model.

toby
12-29-2003, 03:13 PM
yea, it looks like you started with a normal tube then deformed the ends, which will always end up with non-planars.

wingwalker
12-29-2003, 03:18 PM
surface editor.>.make double sided...should solve it!!

SLAYER
12-29-2003, 03:36 PM
It cannot get much more simple than this, but any non sub-d modeling I do, I get the same results in rendering.

Points are all merged. No non-planars. Double sided helped a little, but did not fix.

If I 'TAB' everything is fine, but on this model I do not want to.

SLAYER
12-29-2003, 03:38 PM
Poly Stats

SLAYER
12-29-2003, 03:40 PM
render:

toby
12-29-2003, 04:38 PM
I can only guess that your 'flatness' limit (general options) is set too high, that will show a polygon as planar even when it's not. It's impossible to distort the ends of a cylinder made of quads and not have non-planars.

Try tripling all the polygons and the gaps will go away.

SLAYER
12-29-2003, 05:03 PM
Flatness limit is .5%?
If I lower it to 0 then the non-planars show in the stats window. Is not .5% the default and would I benefit changing this?

Yes, it does go away if I triple, but this does not seem like it would be necessary. I have seen huge awesome models by folk that are in quads and they do not appear to have these issues.
What gives?

Thanks

toby
12-29-2003, 05:33 PM
.25% is what mine is set at - I think it's the default.

toby
12-29-2003, 05:38 PM
And folks that do big awsome models also check for non-planars and triple them or flatten them.

Fabio
12-29-2003, 10:08 PM
I have tried every possible combination on a tube here

simple tube
deformed ends using shear
deformed ends by hand with rotate and stretch
double sided surface setting
doubled polygons - (copy and paste)
doubledpolygons with welded points
doubled polygons with welded points and double sided surface

and on and on -

I cannot duplicate this - I have deformed polygons to ensure they are non planar - I have detached them - slightly altered them everything -- I cannot replicate it

I have tried different types of lights and no joy - i just cannot seem to replicate this issue..

I even tried a whol host of boolean ops cutting away with larger tubes at angles and cubes etc.. and messing about with the polygons then and still no joy..

it's not a non planar issue- it appears to be occuring on the edges of adjacent polygons as if they were not actually joined..




you started with a normal tube then deformed the ends, which will always end up with non-planars


It's impossible to distort the ends of a cylinder made of quads and not have non-planars.

Not strictly true - if you use shear tool or indeed slice off the ends then you will retain the planarity of the remaining polygon sides of the tube..


Also, I have render level of 10 in my layout render options
Doesn't apply unless you have made these polygons sub d before rendering ;)


I would be interested to have the same object and scene file to try out here and try and deduce the cause of it - send it to my email at [email protected] please :)

Fabio
12-29-2003, 11:19 PM
OK Slayer sent me his object file and the first thing that was apparent was that his screengrabs didn't actually truly illustrate how deformed the tube ends were.

They were flattened on opposing axis which naturally makes the polygons uber non-planar indeed.

tripling them solved the problem :)

SLAYER
12-30-2003, 12:28 AM
Thanks for all of the help.

Now I have a question on smoothing. If I have different parts on layers with different surfaces applied some of them get weird looking color/shadow type issues in modeler which carries over to the render. I am able to fix the majority of these individual surfaces by changing the smoothing in the surfaces panel. Is that what I should do? Some of these do not seem to really go away until I crank it up to like 330%. Some do not completely go away at all.

I have made this question its own thread as well.

Thanks.