FAQ : Frequently Asked Questions
  Povanim   for   Blender
jean-michel soler 2002 - 2004

FAQ : Frequently Asked Questions
I am pretty good with blender on its own and can make scenes with povray on its own. Is it possible to leave things out of the export from blender and add povray lights etc...

Answer :
Of course! The file named main<yourfile>.pov loads, using the "includes files", a file named lamp<yourfile>.inc where you can add all the lights you want.  See the page : povanim_filestruc_en.htm

By default, the script exports all the constituant elements of the scene but you can chose to make a selective exportation by suppressing one or the other element, like lamps, materials or camera, even meshes. There are several buttons in the main window for that, see:
 Although, I think that it is not a good idea. In fact, you'd better set the elements into position in blender, export them, and then modify the ones you want in the generated povray's files.

Why is the scene always too bright no matter how much my lamp is turned down, is this a gamma problem?
Answer :
Only an material problem. To correct that you can read suggestions in this page:
I have to use a gradient world background to make things look better however (and with my models as well) gradients always look blotchy and look like I dont have OSA switched on even though its set on 16 when I export.
Answer (very old) :
Sorry,  but for the moment,it is impossible to read the OSA value trough the python interface, but you can set your own AA values in the main<yourfile>.ini exported file:
...An object which has two materials assigned in blender has only one exported . I use Blender 2.23 and Povanim 14j.
Answer :
You are right, there can be only one material "object",  (actually your two materials are linked to the object, what can works well in blender but is difficult to analyse  through the NMesh module of Python/Blender).

If you want that indices to be taken into account in povanim they have to be tied to the "mesh".

I have a prob with the povanim-script. I always get this error when i want to export the scene: "string index out of range".
Answer :
That's right, as long the handled object does not have a name, it doesn't work. Everything works fine as soon as a name is given.
...How can I export an object without its uvmapping ?
Answer :
I should add a new option to deactivate this exportation. Meanwhile,  you can at least suppress the description in the file mesh-myfile.inc by finding the part of the code concerned and by adding the slashes at the right place the way i did hereunder:
//Mesh number: 3
#declare Plane_009 = mesh2 {vertex_vectors{ #include "test_Plane_009verts.inc"}
           // uv_vectors{ #include "test_Plane_009uvco.inc"}
                       normal_vectors{ #include "test_Plane_009norm.inc"}
                      texture_list{ #include "test_Plane_009text_list.inc"}
                       face_indices{ #include "test_Plane_009faces.inc"}
                       normal_indices{ #include "test_Plane_009nindice.inc"}
           // uv_indices{ #include "test_Plane_009uvind.inc"}
                       // uv_mapping
.Well... now i have another problem.
If i want to export a bigger scene, blender takes about 700 Mb memory ! If you first calculate everything, would it be a big problem to change it ?
Yes, it is a big problem. It will certainly be improved in the future versions of blender when the Blender module 2.10 has desappeared (because it seems that this module is responsible for the big slow-down). 

The congestion of memory is typically a blender problem (this was improved since blender 2.10 !!!).
Under windows you can free memory with an adapted tool.
As for the script itself, it exports each object separately and the variables that store data are freed at the end of each exportation.

With me, Povanim last version has a strange behavior : The exportation is made correctly , the bump goes, the textures goes, in a word everything that is in blender is exported in POV. The objection is the exportation time . For a single mesh subdivided once with 2500 faces (5000 triangles) at arrival : 6 HOURS exportation that's too much !.
Answer :
There are two reasons to this problem : the supervision of each mesh point after point, face after face to avoid the errors of exportation. And the use of Blender2.10 to pick up the main texture. Two points that are going to desappear as soon as I get time to complete the present version.

But you can save A LOT of time at once, simply by controlling the free RAM at the beginning of exportation. Blender doesn't free the storage stacks under windows, even if python cancelled all the variables at the end of the script processing. Normally the module even erase its own traces at the end of use .

It's very likely that this duration, 6 hours, is the result of the using of virtual memory. A cleaning up such as Winsystem98 can speed up things  ...

The exportation of about 5000 faces with sorting of the textures is done in a few seconds on a P3/600Mhzs, if you start it rightly after the launching of blender.

You have to know : that povray only works with triangles, thus 5000 quad faces exported result in 10000 triangular faces in povray ; And that each vertex of each face can have its own texture (if you are playing with vertex color, for instance) , that is to say an increasing number of different textures :
30000 of capacity (in actual fact much less, because on the worst case a color put in a vertex is shared by the verteces of the nearby faces, in spite of that we reach 10000 different textures).

Povanim can export all the textures without cleaning the redundant textures. By default, the cleaning is done and it goes pretty fast. But it is absolutely possible to cancel it.

For the above mentionned example, with a Subsurf at 1 we reach  40000 exported faces ;  what takes the most time is the sorting of textures : 10 minutes ; at arrival we have only two left for a capacity of 10000. A few minutes lost during exportation but how many hours (and Mbts of RAM) gained during the rendering ?

All this was improved

Question :
I do not understand the povanim organization.
Answer :

A main page with all the choices continually visible, secondary pages to change the details, but always less than one mouse click far from the main page, to avoid enclosed menus ; with those you have to go through 36 levels before knowing if a choice is available or not.

Question : 
There is this option "Global Settings" which displays the parameters as commentary what is its utility...
Answer :
This is only a supplementary service to avoid having to care of those parameters, that is to say that the script deals with that for you. After that, you only need a few keyboard types to reactivate the options and use them. Povanim is not an inflexible system . The actual structure is due to numerous and various demands, very often if a single user doesn't see the usefulness of an option, there's always someone, somewhere who will be happy to have it.

Question :
I really feel annoyed with the great number of ".inc" files. Can't you do something to gather them ?
There is several good reasons for the presence and the use of such files in great number. On the whole it facilitates the word processing and increase the efficiency of exportation from blender even if you do not see it at once. 
  More over when you export an animation only the changed data between two frames are computed and exported (that means saving time).  And that's a thing only "include" files can do. If we gather all those data in the same file we would have a big increase in space occupied by data and also a raise in exportation time.


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