Yafray artifacts.

I started with a cylinder, chose the top points extruded inwards, then extruded down to form a glass. I close up the inner bottom face with shift F. It renders ok with yafray. However, when I use smooth then render it with yafray I get a whole lot of artifacts. Doing Ctrl-n to redo the normals makes no difference.

http://gallery.mudpuddle.co.nz/albums/somen/artifact.jpg

What am I doing wrong here?

I’m not a Yafray user, but perhaps should you ‘Beauty’ divide your mesh along in its ‘height’ to have more points in this direction. This might help solve, as well as not. Can’t help further if it’s a yafray specific trouble: does a Blender render give the same artefacts? First thing to check, I think. I hope someone could come with an explanation for that.

Beautify made no difference, but thanks all the same because now I know what beautify does.

With the blender render there are no problems.

:slight_smile: It’s among my fundamentals about Blender, one of the very first useful modeling trick I learned… Glad I could show this tip to someone, at my turn!

IIRC, I found the explanation in the 1.5 blender manual… This one is still a very good buy, as ALL the keys, buttons and quite anything else is extensively explained which is not fundamentally the case in 2.0 guide. Sure it’s outdated, but less than the 2.0 in my taste. I wonder if there are still some in the BlenderShop…?

So it’s beyond my skills. There were so many Yafray renders lately I’m pretty sure someone will come with an answer to your case. Keep up :slight_smile:

I cant check it for you now, but I think I have met the same problem before. You are fasing a normal problem.

First try to set a transparant material, some IOR, and render the scene with Blender internal raytracer. I think you will get the same problem.

If this is true, you can solve the problem as follow, go in edit button. Select all verticles an press Shift+N, this wil flip all the normals outside. Maybe if all normals ARE facing outside, sometimes Shift+N doesnt work.

Rerender and I think your problem will be solved.

Hope I’m right,

Walibie

The pb seems to be deeper:

I have looked at normals with no success. I guess I would be interested if you followed the procedure I did and you didnt have the problem. Perhaps its a problem with the linux version of yafray.

Sorry, I didnt saw you did already Shift+n. I think it has to do something with triangles in your mesh instead of quads. But then you will see the artifacts with the blender internal render too. Are you yust using the smooth function or also auto-smooth? If I have this problem, auto-smooth is usually the solution.

If I’m at home I’ll install blender(new computer) and try to look if the windows version of yafray has the same problem.

Greetings,

Walibie

Indeed autosmooth does work and no artifacts. :slight_smile: