Hi. Hopefully this is appropriate for this group. I've been using Blender
for modeling a bit recently. It has several export options. One uses a
script called Povanim to export POV-Ray mesh objects. Another can export to
(wavefront?) .obj files. If I export a model as OBJ, and use Poseray to
convert it to POV-Ray meshes, the resulting POV meshes are substantially
more smooth than the POV-Ray meshes directly created through Povanim. I'm
exporting the same exact Blender model each time.

Are there any fundamental differences in formats that would cause this? I
really don't know exactly what i'm asking. I guess it's something along the
lines of, "Do OBJ files contain some optimized smoothing parameters that
Poseray understands and maintains?" Or is it most likely a deficiency in the
Povanim script that exports from Blender to POV-Ray meshes?

I'd be content with a Blender->OBJ->Poseray->POV-Ray workflow, but I can't
figure out how to export multiple OBJ files from a blender mesh. (one mesh
per "layer" in blender ideally). If I have a mesh in layers 1, 2, and 3 in
blender, I end up with them all in one OBJ file.

On a side note, Blender seems really slow at exporting for some reason.
Maybe a python speed thing, since i think all of it's export scripts are
written in python. That however is cheap shot at python, since i really know
nothing of it's performance compared to compiled C or C++ code.

Anyway, thanks for hearing me out on this longwinded question and
observation. Anyone usign Blender and have a decent workflow process?

-ross

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PoseRay always creates POV mesh files with normals at each vertex. If 
Povanim does not the mesh will appear faceted.

FlyerX


Ross wrote:
> Hi. Hopefully this is appropriate for this group. I've been using Blender
> for modeling a bit recently. It has several export options. One uses a
> script called Povanim to export POV-Ray mesh objects. Another can export to
> (wavefront?) .obj files. If I export a model as OBJ, and use Poseray to
> convert it to POV-Ray meshes, the resulting POV meshes are substantially
> more smooth than the POV-Ray meshes directly created through Povanim. I'm
> exporting the same exact Blender model each time.
> 
> Are there any fundamental differences in formats that would cause this? I
> really don't know exactly what i'm asking. I guess it's something along the
> lines of, "Do OBJ files contain some optimized smoothing parameters that
> Poseray understands and maintains?" Or is it most likely a deficiency in the
> Povanim script that exports from Blender to POV-Ray meshes?
> 
> I'd be content with a Blender->OBJ->Poseray->POV-Ray workflow, but I can't
> figure out how to export multiple OBJ files from a blender mesh. (one mesh
> per "layer" in blender ideally). If I have a mesh in layers 1, 2, and 3 in
> blender, I end up with them all in one OBJ file.
> 
> On a side note, Blender seems really slow at exporting for some reason.
> Maybe a python speed thing, since i think all of it's export scripts are
> written in python. That however is cheap shot at python, since i really know
> nothing of it's performance compared to compiled C or C++ code.
> 
> Anyway, thanks for hearing me out on this longwinded question and
> observation. Anyone usign Blender and have a decent workflow process?
> 
> -ross
> 
>

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Ross wrote:
> Hi. Hopefully this is appropriate for this group. I've been using Blender
> for modeling a bit recently. It has several export options. One uses a
> script called Povanim to export POV-Ray mesh objects. Another can export to
> (wavefront?) .obj files. If I export a model as OBJ, and use Poseray to
> convert it to POV-Ray meshes, the resulting POV meshes are substantially
> more smooth than the POV-Ray meshes directly created through Povanim. I'm
> exporting the same exact Blender model each time.
> 
> Are there any fundamental differences in formats that would cause this? I
> really don't know exactly what i'm asking. I guess it's something along the
> lines of, "Do OBJ files contain some optimized smoothing parameters that
> Poseray understands and maintains?" Or is it most likely a deficiency in the
> Povanim script that exports from Blender to POV-Ray meshes?
> 
> I'd be content with a Blender->OBJ->Poseray->POV-Ray workflow, but I can't
> figure out how to export multiple OBJ files from a blender mesh. (one mesh
> per "layer" in blender ideally). If I have a mesh in layers 1, 2, and 3 in
> blender, I end up with them all in one OBJ file.
> 
> On a side note, Blender seems really slow at exporting for some reason.
> Maybe a python speed thing, since i think all of it's export scripts are
> written in python. That however is cheap shot at python, since i really know
> nothing of it's performance compared to compiled C or C++ code.
> 
> Anyway, thanks for hearing me out on this longwinded question and
> observation. Anyone usign Blender and have a decent workflow process?
> 
> -ross
> 
> 
Don't use Blender at all.  But my first guess is that it is about the 
calculation of the normals, and when that is being done.  Maybe if you 
take a simple object made in Blender and run it through each workflow 
and open the files along the way to compare the normals?  Unless the 
normals are actually being regenerated by poseray then it might be that 
the Blender -> mesh2 script in Blender is different from the Blender -> 
.obj script in Blender.

Might also be interesting to edit out the normals at different points in 
the process and see what happens.

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Jim Charter <jrc### [at] msncom> wrote:
> Don't use Blender at all.  But my first guess is that it is about the
> calculation of the normals, and when that is being done.  Maybe if you
> take a simple object made in Blender and run it through each workflow
> and open the files along the way to compare the normals?  Unless the
> normals are actually being regenerated by poseray then it might be that
> the Blender -> mesh2 script in Blender is different from the Blender ->
> .obj script in Blender.

Hi!

Povanim produces only half the number of normal indices as PoseRay does.

I imported a Wavefront.obj (made with Wings3D) into Blender to animate it.
  ==
Exporting it with Povanim resulted in
 1184 faces
 594  vertex vectors
and 594 normal indices

Exporting with PovRay gave me
 the same number of faces and vertex vectors
but 1184 normals

I think it's not a matter of Povanim but of blender itself, as the rendered
image in POV-Ray looked as ugly as the blender render with all the visible
faces especially when having a Glass material.
With PoseRay it looked really good (as usual).


Now I'm looking for alternatives for animation.
Tried 3DCanvas but that program is really a  p. i . t. a.

Yours,
Burki

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"Burki" <nomail@nomail> wrote in message
news:web.4267e4f2de0cce51d61e8c370@news.povray.org...
> Povanim produces only half the number of normal indices as PoseRay does.
>
> I imported a Wavefront.obj (made with Wings3D) into Blender to animate it.
>   ==
> Exporting it with Povanim resulted in
>  1184 faces
>  594  vertex vectors
> and 594 normal indices
>
> Exporting with PovRay gave me


Do you mean "Poseray" in the line above?


>  the same number of faces and vertex vectors
> but 1184 normals
>
> I think it's not a matter of Povanim but of blender itself, as the
rendered
> image in POV-Ray looked as ugly as the blender render with all the visible
> faces especially when having a Glass material.
> With PoseRay it looked really good (as usual).
>
>
> Now I'm looking for alternatives for animation.
> Tried 3DCanvas but that program is really a  p. i . t. a.
>
> Yours,
> Burki
>


The desire to try out animation is why I wanted to use Blender. One question
for you, if you import the OBJ into Blender, then export a new OBJ with
Blender, does it retain all of it's original vertex information?

thanks,
ross

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Ross wrote:
> Do you mean "Poseray" in the line above?
Yes.

> if you import the OBJ into Blender, then export a new OBJ with
Blender, does it retain all of it's original vertex information?


I do not have the export script to export as .OBJ script (from blender).
But when I export with Povanim into POV-Ray, the number of vertices stays
the same while the faces nearly double:

Original Wings3D:
2550 vertices
2554 faces
and 1 normal / face

imported into Blender (via .OBJ)
2550 vertices
2554 faces
?        normals

exported into .pov (with Povanim)
2550 vertices
5096 faces (I did not triangulate manually ! )
2550 normals  ----> one normal / vertex (aha?)


Importing the .OBJ into PoseRay  ---->
Number of vertices............. 2550
Number of normals.............. 2550 (1normal / vertex)
Number of polygons............. 2554
Number of valid triangles...... 5096.

So, Povanim seems to triangulate automtically and sets one normal per
vertex. But the doubling of faces without having a doubled number of
normals won't do any smoothing effect.
PoseRay seems to have a different way to calculate, but how...
 --- I'm as informed as a tea leaf about the East India Company.

And ani was also for me the reason to take a look at blender.

Yours,
Burki @ ginko . de .keinen spam!

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"Burki" <nomail@nomail> wrote in message
news:web.42683208de0cce51d61e8c370@news.povray.org...
> Ross wrote:
> > Do you mean "Poseray" in the line above?
> Yes.
>
> > if you import the OBJ into Blender, then export a new OBJ with
> Blender, does it retain all of it's original vertex information?
>
>
> I do not have the export script to export as .OBJ script (from blender).
> But when I export with Povanim into POV-Ray, the number of vertices stays
> the same while the faces nearly double:
>
> Original Wings3D:
> 2550 vertices
> 2554 faces
> and 1 normal / face
>
> imported into Blender (via .OBJ)
> 2550 vertices
> 2554 faces
> ?        normals
>
> exported into .pov (with Povanim)
> 2550 vertices
> 5096 faces (I did not triangulate manually ! )
> 2550 normals  ----> one normal / vertex (aha?)
>
>
> Importing the .OBJ into PoseRay  ---->
> Number of vertices............. 2550
> Number of normals.............. 2550 (1normal / vertex)
> Number of polygons............. 2554
> Number of valid triangles...... 5096.
>
> So, Povanim seems to triangulate automtically and sets one normal per
> vertex. But the doubling of faces without having a doubled number of
> normals won't do any smoothing effect.

I might have time to experiment tonight. I don't think work would appreciate
me playing with Blender :)


> PoseRay seems to have a different way to calculate, but how...
>  --- I'm as informed as a tea leaf about the East India Company.

LOL. Nice analogy :) I know I've seen the author of Povanim post to
povray.binaries.images, so maybe he's lurking around here somewhere...

>
> And ani was also for me the reason to take a look at blender.
>

How have you fared with it? I'm just starting to practice modeling, no
animation stuff yet.


> Yours,
> Burki @ ginko . de .keinen spam!
>
>

Thanks for the info!
-ross

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"Ross" <rli### [at] everestkcnet> wrote:
> I might have time to experiment tonight. I don't think work would appreciate
> me playing with Blender :)
>
> I know I've seen the author of Povanim post to
> povray.binaries.images, so maybe he's lurking around here somewhere...
>
>
> How have you fared with it? I'm just starting to practice modeling, no
> animation stuff yet.
>
> -ross

I found the most boring work in animation was the proper assignment of
vertices to the bones. And in the end I was a bit disapointed about the
visible
facets / faces.
Very good help were some tutorials from  Lyubomir, especially the foot
design:
      http://blenderchar.weirdhat.com/tutorials.php
What I did was a spider animation. Eight feet. After that I won't do a
centiped.

Yours,
Burki

pm. won't be back until Thursday, good luck!

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FlyerX wrote:

> PoseRay always creates POV mesh files with normals at each vertex. If
> Povanim does not the mesh will appear faceted.
> 
> FlyerX
> 

So for some reason, given a mesh named MyObjext, Povanim is exporting a file
called MyObjectCube1nindice.inc and in that file is just this: "0,"

It also creates a file called meshMyObject.inc which contains:

// BEGIN FILE

//Mesh number: 1
#declare Cube1 = mesh2 {
  vertex_vectors{ #include "MyObjectCube1verts.inc"}
  normal_vectors{ #include "MyObjectCube1norm.inc"}
  face_indices{ #include "MyObjectCube1faces.inc"}
  normal_indices{ #include "MyObjectCube1nindice.inc"}
}

object{ Cube1 
  pigment{rgb<0.8,0.8,0.8>} 
  scale<1.0,1.0,1.0> 
  rotate<89.9999956743,-0.0,0.0> 
  translate<0.0,0.0,0.0> 
}

// END FILE

So when that nindice file gets included in the "normal_indices {...}"
statement, it basically overrides POV-Rays behavior stated in section
2.3.2.2.1 of the manual:

"In case we want a smooth mesh, the same steps we did also apply to the
normals in a mesh. For each vertex there is one normal vector listed in
normal_vectors{}, duplicates can be removed. If the number of normals
equals the number of vertices then the normal_indices{} list is optional
and the indexes from the face_indices{} list are used instead."

commenting out the normal_indices {...} line in the meshMyObject.inc file
caused the object to be rendered with POV-Ray in a smooth manner.

So that's cool. I think I can safely use Blender+Povanim+POV-Ray without
worrying about flat-faced meshes.

happy tracing!
-ross

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Smooooooooooth  !

Thanx Ross,
This have been the most sophisticated slashes I ever included !

Bu.

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