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Jack D
09-16-2010, 02:16 PM
I'm not sure what's up here. I have been working with a sub D mesh and getting just the way I want it. Then, I take it into Layout to do some renders and find these breaks. They can not be seen in modeler or layout only in the render. What's up and how do I fix it now?

stevecullum
09-16-2010, 02:26 PM
Its a bit hard to tell exactly what's going on there - can you upload the model?

Sensei
09-16-2010, 04:03 PM
Duplicated polygons and/or 2 point polygons. Check in Polygon Statistics window in Modeler..

Jack D
09-16-2010, 07:44 PM
sorry, I didn't realize how bad that first pic. was. Here is a better one. I wouldn't mind uploading the file accept I don't know how. Give me the low down on how and I'll do it. I did check for 2 point pollies and duplications and I don't think there are any.

Sensei
09-16-2010, 07:52 PM
It looks like ray-tracing can't hit polygon, and flies through object, and we see environment background gradient behind it..

We need lwo and lws to reproduce it here and suggest solution. Pack them to ZIP and in advanced writing messages attach file..

Are you using Classic Camera, or Perspective?

What is size of object? Maybe it's too big like kilometers or so?

probiner
09-16-2010, 07:53 PM
You might experiencing issues with the normals of the polygons, because they are:

- N-gons
- Non-planar
- Concave (red in the image)
87359

Some possible fixes:
- Normal Corrector (http://www.lwplugindb.com/Plugin.aspx?id=20e5fbf4) (use in modeler). Will recalculate polygons normals.
- 'Connect' specific vertices from polys that fit the descriptions above so that they get more quad/tri, more planar or convex.
- 'Triple'. It's like using 'Connect' indiscriminately. So do it to specific polygons and check if the smoothing renders well.
- 'Flatten' will make a poly planar, but if the normal is screwed up, this might not work properly.
- Janitor (http://www.chrisepeterson.com/lscripts.php) with '0 polygon points' and 'triple nonplanar' UNchecked. It will cleanup the model.

To attach an object file, go to advanced reply and click the -paper clip- icon, browse file and upload.

Good Luck

Sensei
09-16-2010, 07:57 PM
None of these apply in this case, if he has sub-patches (at least that is what he mentioned in initial post).. Sub-patches are never non-planar, and never n-gons and always triangles in Layout renderer..

probiner
09-16-2010, 08:19 PM
Crap i keep misreading posts. I looked to the image and didn't seem subdivided to me.
Oh well... sry.

I think i never had this error with a SubD surface.

Jack D
09-17-2010, 12:54 AM
Sorry guys, I didn't explain this very well. It was a sub-D object, I froze it and now have been tweaking it. I think the breaks happened after I subdivided it and smoothed out the whole area, but I'm not sure. That is the only tweak I've made to this part.
How do I package the object file so I can zip it?

The best I can do is this obj. file. you can still see the breaks in the nose.
Thanks for the help!

Sensei
09-17-2010, 07:09 AM
You said you don't have duplicates?

But after loading your model to Modeler, pressing 'm' to Merge Points, there was 419 points duplicated. Then pressed 'shift-i' to Unify Polygons and there was 8 duplicates..

After using Merge Points with Fixed distance 1 mm, there is even more- 1300.. But I am not sure whether you have or not so close real geometry. Maybe these are false positive.

Anyway, in areas where you found "breaks" select points in Modeler and press "i" to open Information window. Probably you will find that some very very close to each other points are there. Weld them together.

3DGFXStudios
09-17-2010, 07:21 AM
I checked your model but, I don't want to be rude but it just badly modeled. If you want to use subD you can use a lot less polygons. I think it's wise to follow some good subD modeling tutorials.

edit: I missed the freezing part. But than my question is why did you freeze it? I think it a good idea to go back to the unfreezed version. That way we can tell you more and help you better.

Jack D
09-17-2010, 01:00 PM
Again guys thanks for your help, I am painfully aware of how poor my modeling skills are. Your patience is very much appreciated. I am always looking for some good tutorials to get better. If you know of some that could help out I would love to have the link. I watched Larry's transport ship modeling tut, and that is where I came up with this model.
I have tried again to find duplicated points in the area of the breaks, (this is what I tried at first). Looking at the render it seems they should be there but I can't find them,(Very frustrated)
I froze the sub d object so I could add more detail and sharpen the round edges. The nose needed to have more geometry added to smooth it out. I think I did it the wrong way and caused the breaks. I'm not sure what the right way to handle it would have been.
Here is the sub D file, I'll take all the help I can get.

Sensei
09-17-2010, 01:20 PM
Models like cars, airplanes, boats, people model first using spline modeling.

When spline cage is done, spline patch them, and then it's dense enough to convert to sub-patches without dramatically changing general shape. Then you can bevel, multi-shift etc add details.

In your case, sub-d is so low poly, any movement of point has drastically result to whole object.

I have made automatic spline modeling plugin called EasySpline, which visualize spline cage as virtual geometry.
http://www.easyspline.com
Making this jaguar car took less than 10 minutes
http://www.spinquad.com/forums/showthread.php?13888-Spline-modeling-Jaguar-car&highlight=jaguar
Since post 18 I started little tutorial with screen-shots for each single stage.

JeffrySG
09-17-2010, 01:27 PM
Again guys thanks for your help, I am painfully aware of how poor my modeling skills are. Your patience is very much appreciated. I am always looking for some good tutorials to get better. If you know of some that could help out I would love to have the link.

You might benefit from watching some of my subd video tutorials. Link is in my sig and they're all free. They start basic but they'll teach you some good subd techniques.

probiner
09-17-2010, 01:39 PM
You might benefit from watching some of my subd video tutorials. Link is in my sig and they're all free. They start basic but they'll teach you some good subd techniques.

:agree:

jeric_synergy
09-17-2010, 01:47 PM
What Jeffry said: his tutorials are very good indeed.

EDIT: and what probiner said even more succinctly.