I have been using Poseray to convert 3ds and Poser human models into udo's
to use in Moray. But when I render with radiosity I get ugly artefacts,
black stripes appear around the edges. If I convert the udo to a mesh2
object in Moray then these artefacts dissappear completely.

Mesh2 objects are huge compared to udo's, the pov file size
in one recent rendering grew from 3kb to over 10,000kb just by converting
a single udo to mesh2.

In the scene I'm currently working on I need 12 human models and of course
other stuff as well and I'm fearing the final file size will grow to a
something
my system can't cope with.

Does anyone know what causes these artefacts and what can be done?
Is is Poseray or is it the udo format?

Post a reply to this message

"Hildur K." <hil### [at] 3dcafemailevery1net> wrote:
> I have been using Poseray to convert 3ds and Poser human models into udo's
> to use in Moray. But when I render with radiosity I get ugly artefacts,
> black stripes appear around the edges. If I convert the udo to a mesh2
> object in Moray then these artefacts dissappear completely.
>
> Mesh2 objects are huge compared to udo's, the pov file size
> in one recent rendering grew from 3kb to over 10,000kb just by converting
> a single udo to mesh2.
>
> In the scene I'm currently working on I need 12 human models and of course
> other stuff as well and I'm fearing the final file size will grow to a
> something
> my system can't cope with.
>
> Does anyone know what causes these artefacts and what can be done?
> Is is Poseray or is it the udo format?

I posted examples here

http://news.povray.org/povray.binaries.images/thread/%3Cweb.42b56db48e5662c19f947fd80%40news.povray.org%3E/

Post a reply to this message

...
> Mesh2 objects are huge compared to udo's, the pov file size
> in one recent rendering grew from 3kb to over 10,000kb just by converting
> a single udo to mesh2.
...
The udo file is only for displaying in Moray, it's the accompanying include
file that's rendered. When you convert the udo to a mesh2 the information is
stored in the pov file instead of the separate include file. Another thing
about udo to mesh2 conversions (in Moray) is that the surface normal
information is lost, the udo format was not designed for conversion
purposes. Are you using surface subdivision?

Stephen

Post a reply to this message

"StephenS" <sshonfield(at)ottawa(dot)net> wrote:
> ...
> > Mesh2 objects are huge compared to udo's, the pov file size
> > in one recent rendering grew from 3kb to over 10,000kb just by converting
> > a single udo to mesh2.
> ...
> The udo file is only for displaying in Moray, it's the accompanying include
> file that's rendered. When you convert the udo to a mesh2 the information is
> stored in the pov file instead of the separate include file. Another thing
> about udo to mesh2 conversions (in Moray) is that the surface normal
> information is lost, the udo format was not designed for conversion
> purposes. Are you using surface subdivision?
>
> Stephen

Basically I'm using a 3ds model, a triangular mesh of good quality, editing
and posing it in 3ds Max and want to use it (12 times) in a Moray/Povray
radiosity scene.
Poseray offers a 3ds to udo conversion which works fine as I'm not editing
the model in Moray anyway. I don't know of any other software to do this
kind of conversion.
The only problem are these artefacts, but they (almost) dissappear as soon
as I convert to mesh2.

Are you saying that udo was never ment to be used for scene objects? It
smoothes the surfaces nicely in rendering.
When I convert to mesh2 I use surface subdivision level 1 to get a similar
level of smoothness as in the 3ds, so it's not that I've overdone the
subdiv level.

I have been joggling with this for some time. Higher AA settings don't have
any effect, I've tried all sorts of combination of conversion optimation
settings in Poseray and I've tried to change mesh density in the original
3ds file so far.

Another problem is the texturing issue. When you convert to mesh2 you lose
all original texures and have to make a UV map instead. Which always
crashes Moray by the way.

Using udo you can keep the original textures from Poser or Max and they
convert with the model to Pov textures which then can be edited later.

Maybe this isn't a big problem, except for the fact that the mdl file will
become enormous with 12 figures in it and probably will be prone to crash.

The rendering times are a little bit slower for mesh2,
in the posted example (see above) the udo rendered in 5m00sec and the mesh2
in 5m19sec. Not too bad.

Post a reply to this message

...
> Basically I'm using a 3ds model, a triangular mesh of good quality,
editing
> and posing it in 3ds Max and want to use it (12 times) in a Moray/Povray
> radiosity scene.

Do you export as .3ds or .obj?

> Poseray offers a 3ds to udo conversion which works fine as I'm not editing
> the model in Moray anyway. I don't know of any other software to do this
> kind of conversion.
> The only problem are these artefacts, but they (almost) dissappear as soon
> as I convert to mesh2.
>
> Are you saying that udo was never ment to be used for scene objects?
The User Defined Object (udo) is two files, one for displaying in Moray
(.udo extension), and one for rendering in POV-Ray (.inc extension). The
.inc file is the full scene object.

...
> Maybe this isn't a big problem, except for the fact that the mdl file will
> become enormous with 12 figures in it and probably will be prone to crash.
If the figures are all the same, have you tried "Duplicate", with "Create
References"?

I don't use 3ds Max or Poseray, so some of this is just guessing. Hopefully
some how know what there talking about will speak up :-)

Stephen

Post a reply to this message

"StephenS" <sshonfield(at)ottawa(dot)net> wrote:


> Do you export as .3ds or .obj?

I export as .3ds as Max doesn't support .obj.

I don't use 3ds Max or Poseray, so some of this is just guessing. Hopefully
> some how know what there talking about will speak up :-)
>
Actually you got me thinking and I did some research. Which left me with
more questions (of course). Thanks anyway.

I looked into the udo ascii text file and there is a definition of a mesh.
It refers to an .inc file which has an almost identical definition of a mesh
as the .udo but there the object is declared as a mesh2 object.

So this particular udo object is really a mesh2 object!

But this doesn't completely answer my original quesion, on the contrary it
makes it more curious. Why does a udo referring to a mesh2 object generate
artefacts while Morays own mesh2 does not?

The only thing I can think of is the quality of the mesh2 object. I noticed
thart the inc file containing the mesh is only about 1,800kb but the
exported Moray's converted to mesh2 pov file is around 10,000kb.

This must have someting to do with faces. The udo smoothes the model nicely,
but when I convert to mesh2 in Moray the model appeares faceted.
Subdividing once is enough to smooth in this case but that means of course
5 times bigger output.

But this still doesn't quite explain the artefacts, or does it? I'm not
sure.

Comments anyone?

Hildur

Post a reply to this message

Hi Hildur K., you recently wrote in moray.win:

> Another problem is the texturing issue. When you convert to mesh2 you lose
> all original texures and have to make a UV map instead. Which always
> crashes Moray by the way.
Can you give me the steps that cause a crash when you use a UV map?

- Lutz
- Lutz
  email : lut### [at] stmuccom
  Web   : http://www.stmuc.com/moray

Post a reply to this message

Hi Hildur K., you recently wrote in moray.win:

> So this particular udo object is really a mesh2 object!
> 
> But this doesn't completely answer my original quesion, on the contrary it
> makes it more curious. Why does a udo referring to a mesh2 object generate
> artefacts while Morays own mesh2 does not?

So, as you probably realise by now, the UDO file simply contains the
mesh representation that Moray should display in order to allow you to
manipulate the object. What you see in Moray is in NO WAY exported to
or renderered by POV-Ray. Moray simply exports an include statement
that makes POV-Ray read and render the .inc file that your conversion
process created.

If you can avoid UDO/INC, you would probably get better results in
Moray. I think that 3DWin will create a mesh2 object with correct
textures, although I'm not sure, I haven't used it in some time.

BTW, texturing a subdivided mesh is a bit buggy, the seams tend to
land in weird/uncontrollable places. But here's a tip: when you have
the mesh object in Moray, set the subdiv setting to 1 and then convert
it to mesh again. This now makes the subdivided mesh a regular mesh
object (i.e. level 0). Now it can be accurately UV mapped.

- Lutz
- Lutz
  email : lut### [at] stmuccom
  Web   : http://www.stmuc.com/moray

Post a reply to this message