Blender26 Ogre Exporter

[lunkhound]

If you want, you can try out the version I put up here: https://bitbucket.org/cc8192/blender2ogre

I did some major refactoring of the way armature animation is exported. The NLA stuff was not working consistently for me, I could export the same animation twice without making any changes in Blender and get completely different results for no apparent reason.
So I've tried to fix that. I got rid of some UI options (only animated bones, and independent animations) that no longer made sense.
This version has not been well tested, and should be considered experimental. I've only used it for exporting meshes and animations, but I've tried not to break any of the many bits I'm not using.

[shenjoku]

I'm trying to use Blender 2.6.6 with ogre2blender 0.6.0 and Tundra 2.5.1 and I'm getting a hang whenever I try to click the helper button in Blender to run Tundra. The Tundra window opens and the Blender console outputs that it succeeded in exporting the scene and that it has started some server thread and then it just sits there and has to be killed. How do you get it to work with Tundra? Do you have to setup a server or something?

[RigoCL]

If you want, you can try out the version I put up here: https://bitbucket.org/cc8192/blender2ogre

...

Damn it! It took me an hour and a half to check this new version with different files and also my own file, and when I hit the "Submit" button I was logged off, losing everything I typed.

In brief... In Win7 and Blender 2.66, I removed the the old version of the exporter, erased the addon directory and installed only the "io_export_ogreDotScene.py" file. After that I tested the "armature-test.blend" file that comes with the exporter, just clicked on the 'snowflake' icon, selected all and exported... the python script crushed, lots of error.

After that I tested "axis.blend", again the python script crushed, lots of error.

Then, I tested "floating-bones.blend", after clicking the 'snowflake' icon and exporting, everything looks ok, there're two skeleton files with the correct animation name.

Finally, I tested this new version using my file with problems (http://www.ogre3d.org/forums/posting.ph ... f#pr499227), well... I can say that I still have the problem, one of my animations is ok in the corresponding .skeleton file, but the one that previously failed, now failed again, with the difference that now there're no translate=<0,0,0>, rotate angle=0, rotate <1,0,0>... instead, there is no data for any keyframe, here's the .skeleton file:

Code: Select all

<skeleton >
  <bones >
    <bone id="0" name="Bone" >
      <position x="0.000000" y="0.000000" z="0.000000" />
      <rotation angle="0.000000" >
        <axis x="-0.000000" y="0.000000" z="0.000000" />
      </rotation>
    </bone>
  </bones>
  <bonehierarchy />
  <animations >
    <animation length="2.458333" name="Armature.001Action" >
      <tracks />
    </animation>
  </animations>
</skeleton>

Though it seems the script is a little bit unstable, the problem for me is that definitely the two animations are not equal, I re checked them on blender and can't find any difference, but I'm sure there's one, so now I will look into the exporter python code to figure out the different behavior (two completely different skeleton files) of the script to find a place to start.

[lunkhound]

If you want, you can try out the version I put up here: https://bitbucket.org/cc8192/blender2ogre

...

Damn it! It took me an hour and a half to check this new version with different files and also my own file, and when I hit the "Submit" button I was logged off, losing everything I typed.

In brief... In Win7 and Blender 2.66, I removed the the old version of the exporter, erased the addon directory and installed only the "io_export_ogreDotScene.py" file. After that I tested the "armature-test.blend" file that comes with the exporter, just clicked on the 'snowflake' icon, selected all and exported... the python script crushed, lots of error.

After that I tested "axis.blend", again the python script crushed, lots of error.

Oh, I never noticed those before! Whoops!
I'm seeing the script crash on some of these too. I'll see about fixing these crashes.

Then, I tested "floating-bones.blend", after clicking the 'snowflake' icon and exporting, everything looks ok, there're two skeleton files with the correct animation name.

Finally, I tested this new version using my file with problems, well... I can say that I still have the problem, one of my animations is ok in the corresponding .skeleton file, but the one that previously failed, now failed again, with the difference that now there're no translate=<0,0,0>, rotate angle=0, rotate <1,0,0>... instead, there is no data for any keyframe, here's the .skeleton file:

Can you post the .blend file?

[lunkhound]

I posted the fix for those crashes with the example blend files:

https://bitbucket.org/cc8192/blender2ogre

[RigoCL]

I finally got it working, my fault anyway.

What I'm not able to export is a Path converted to Mesh, the exporter creates a <node> tag in the .scene file, but no list of points is exported, I don't want to deal with paths to follow directly in Ogre through splines, is there a way this exports works with this kind of meshes with no faces?

[darkbrain]

Hi,
i'm trying to export a simple mesh (suzanne) using blender2ogre (from trunk) and blender 2.66 on windows. The mesh has a material unwrapped onto the mesh, and i'm using shaders from ogre1.9 . I want to use bump mapping so into Ogre material pass1 i have "one zero" with Examples/BumpMappingMultiLight, i've setted a normal texture and a decalm one and the material is . But when i'm trying to export the scene i otain this error:

G:\opt\Blender Foundation\Blender2.66>blender.exe > out
Traceback (most recent call last):
File "C:\Users\darkbrain\AppData\Roaming\Blender Foundation\Blender\2.66\scrip
ts\addons\io_export_ogreDotScene.py", line 3172, in execute
self.ogre_export(self.filepath, context)
File "C:\Users\darkbrain\AppData\Roaming\Blender Foundation\Blender\2.66\scrip
ts\addons\io_export_ogreDotScene.py", line 3535, in ogre_export
material_files = self.dot_material(meshes + force_material_update, path, mat
erial_file_name_base)
File "C:\Users\darkbrain\AppData\Roaming\Blender Foundation\Blender\2.66\scrip
ts\addons\io_export_ogreDotScene.py", line 3374, in dot_material
data = generate_material( mat, path=path, copy_programs=True, touch_textures
=CONFIG['TOUCH_TEXTURES'] )
File "C:\Users\darkbrain\AppData\Roaming\Blender Foundation\Blender\2.66\scrip
ts\addons\io_export_ogreDotScene.py", line 7162, in generate_material
prog.save(path)
File "C:\Users\darkbrain\AppData\Roaming\Blender Foundation\Blender\2.66\scrip
ts\addons\io_export_ogreDotScene.py", line 6420, in save
f = open( os.path.join(path,self.source), 'wb' )
File "G:\opt\Blender Foundation\Blender2.66\2.66\python\lib\ntpath.py", line 1
21, in join
elif isabs(b):
File "G:\opt\Blender Foundation\Blender2.66\2.66\python\lib\ntpath.py", line 1
02, in isabs
s = splitdrive(s)[1]
File "G:\opt\Blender Foundation\Blender2.66\2.66\python\lib\ntpath.py", line 2
08, in splitdrive
if len(p) > 1:
TypeError: object of type 'NoneType' has no len()

location: <unknown location>:-1


i've also these warnings:
WARNING: no shader programs were found - set "SHADER_PROGRAMS" to your path
Warning: addon-module 'io_export_rogremesh' found module but without __addon_enabled__ field, possible name collision from file: 'C:\\Users\\darkbrain\\AppData\\Roaming\\Blender Foundation\\Blender\\2.66\\scripts\\addons\\io_export_rogremesh\\__init__.py'
ogre.toggle_interface ENABLE
WARNING: no shader program named: Examples/BumpMapVP
WARNING: no shader program named: Examples/BumpMapFP

USER_MATERIALS = G:\src\ogre1.9\media\materials
SHADER_PROGRAMS = G:\src\ogre1.9\media\materials\programs

Any help?

tnx,
DarkBrain

[lunkhound]

darkbrain,

From what you posted I can't fully diagnose the problem. About all I can say is that it is something to do with generating the Ogre materials.
I don't really use the exporter to generate materials, I prefer to create the material scripts separately. If you disable exporting the materials, this crash should not happen.

However, the exporter really shouldn't crash like that. If you can share the .blend file, I'll take another look at the exporter and patch it so it at least doesn't crash.

[darkbrain]

darkbrain,

From what you posted I can't fully diagnose the problem. About all I can say is that it is something to do with generating the Ogre materials.
I don't really use the exporter to generate materials, I prefer to create the material scripts separately. If you disable exporting the materials, this crash should not happen.

However, the exporter really shouldn't crash like that. If you can share the .blend file, I'll take another look at the exporter and patch it so it at least doesn't crash.

Thanks for your reply
I attached a simple test.
It's true, it's doesn't crash if i disable materials export. But what do you suggest to create and attach a material?
Anyway if i use tundra materials blender2ogre exports them well, but i don't know ho to use them , i've just started to learn Ogre.

tnx,
DarkBrain

[lunkhound]

OK, I was able to reproduce that crash. Apparently one of the Ogre shader program definitions it parsed had something the exporter didn't like. I patched it so that it prints a warning about the material and program it is unhappy with instead of crashing the export.

My updated version is here:
https://bitbucket.org/cc8192/blender2ogre

I've issued a pull request, but it could be a little while before it gets into the main repo.

About creating materials, what I ended up doing when I started with Ogre was just writing the material scripts by hand, and then in Blender I would create materials with names to match. As long as the names match up it should work.

[darkbrain]

OK, I was able to reproduce that crash. Apparently one of the Ogre shader program definitions it parsed had something the exporter didn't like. I patched it so that it prints a warning about the material and program it is unhappy with instead of crashing the export.

My updated version is here:
https://bitbucket.org/cc8192/blender2ogre

I've issued a pull request, but it could be a little while before it gets into the main repo.

About creating materials, what I ended up doing when I started with Ogre was just writing the material scripts by hand, and then in Blender I would create materials with names to match. As long as the names match up it should work.

Thanks it doesn't crash now. Now i can apply a simple material, now i have to understand how to apply a bump mapping material.

tnx,
DarkBrain

[Mind Calamity]

@DarkBrain: to use normal/bump/specular/etc mapping you have to write your own glsl/hlsl/cg shaders. You can't export those from Blender, unfortunately.

[hymerman]

Some of you may be interested to know, I've forked, fixed up and built the NVIDIA Texture Tools and made an installer available. It's always bothered me that the instructions for the exporter mention NVIDIA Texture Tools but just point to a creaky old google code site with a download from 2010, and mention that if it doesn't work to try the 'legacy tools' which appear to be even older. This fills the void nicely!

GitHub project:
https://github.com/hymerman/nvidia-texture-tools

Installer download. Windows only I'm afraid!
https://github.com/hymerman/nvidia-text ... unofficial

Now there's no excuse for using jpgs and pngs as textures!

[RigoCL]

Hi, I've been dealing with a problem for about a month, unable to solve it. I started to create my own shaders in Ogre3D, so far so good until I started to use those shaders with meshes exported from Blender, the shaders didn't work, no matter what I do but they don't shade "per vertex" any mesh exported from Blender, instead, the whole face is shaded with the same color.

I was confused what the problem could be, lost lots of time blaming the shader as I was just starting to learn how they work, but now my guess is that the Blender exporter is not working "properly", to test it, in Blender I created a simple UV Sphere of 4 (segments) x 4 (rings), the sphere has 16 faces and 14 vertices, so far so good, but when I exported that mesh, the exporter declared to have exported:

Original Vertices: 14
Exported Vertices: 56

The exported amount of vertices is 4 times the original (and correct) amount, I'm pretty sure this "extra" vertices are confusing my shader.

There's more, I opened the created sphere.mesh.xml file, and found the four different vertex definition of what actually is just one vertex in Blender, this is what I found:

Code: Select all

            <vertex>
                <position x="0.000000" y="-0.000000" z="-1.000000"/>
                <normal x="-0.678598" y="0.281085" z="-0.678598"/>
            </vertex>
            <vertex>
                <position x="0.000000" y="-0.000000" z="-1.000000"/>
                <normal x="-0.678598" y="-0.281085" z="-0.678598"/>
            </vertex>
            <vertex>
                <position x="0.000000" y="-0.000000" z="-1.000000"/>
                <normal x="0.678598" y="-0.281085" z="-0.678598"/>
            </vertex>
            <vertex>
                <position x="0.000000" y="-0.000000" z="-1.000000"/>
                <normal x="0.678598" y="0.281085" z="-0.678598"/>
            </vertex>

As you can see from the "position" tag, the four previous vertices are exactly the same, actually (0,0,-1), but the normals are all different, they point in different directions. This difference in the normals is because the normal's pointing direction is calculated according to the face's direction to which the normals belong, for instance, the next three different vertices are part of the same face, so they all have exactly the same normal.

Code: Select all

            <vertex>
                <position x="-1.000000" y="-0.000000" z="-0.000000"/>
                <normal x="-0.678598" y="0.281085" z="-0.678598"/>
            </vertex>
            <vertex>
                <position x="-0.707107" y="0.707107" z="-0.000000"/>
                <normal x="-0.678598" y="0.281085" z="-0.678598"/>
            </vertex>
            <vertex>
                <position x="0.000000" y="0.707107" z="-0.707107"/>
                <normal x="-0.678598" y="0.281085" z="-0.678598"/>
            </vertex>

Now I'm sure that this way of exporting the mesh is confusing my Ogre shader.

I'm not trying to hurt any author's feelings with this, been using this exporter a lot for my Ogre stuff, but now when it comes to shaders, seems the vertices quadruplication and the normal direction's calculation is preventing me to get the desired results.

Any help would be appreciated.

Rigo.

[lunkhound]

RigoCL,

In blender, select your mesh, go into edit mode. Select all faces, then go to Mesh -> Faces -> Shade Smooth.
Then re-export. That should fix it.

[hymerman]

Just to help you understand why that fixes the problem - normals are stored per vertex, then usually interpolated to get a smooth-looking surface. If you want smooth surfaces, that's fine, but if you want flat shading, this has to either be handled specially by storing per-face normals and writing a shader to use them, or you have to duplicate the vertices so each one can have the normal of the face it connects to, which is what the exporter does. Blender has 'smooth' and 'flat' shading modes, and chooses 'flat' by default, so if you don't change it, you'll end up with duplicated vertices on export.

[RigoCL]

RigoCL,
In blender, select your mesh, go into edit mode. Select all faces, then go to Mesh -> Faces -> Shade Smooth.
Then re-export. That should fix it.

I just got confused on what the exporter was doing because when looking at the Normals in Edit Mode, just one is shown per vertex, but it worked great after applying "Shade Smooth".

Thanks.

Just to help you understand why that fixes the problem - normals are stored per vertex, then usually interpolated to get a smooth-looking surface. If you want smooth surfaces, that's fine, but if you want flat shading, this has to either be handled specially by storing per-face normals and writing a shader to use them, or you have to duplicate the vertices so each one can have the normal of the face it connects to, which is what the exporter does. Blender has 'smooth' and 'flat' shading modes, and chooses 'flat' by default, so if you don't change it, you'll end up with duplicated vertices on export.

In my experience solving this problem, there's no need to write a special shader for flat shading. What makes the difference is selecting either "Shade Flat" or "Shade Smooth" in Blender's Edit Mode as lunkhound mentioned, the shader works great for both.

[hymerman]

In my experience solving this problem, there's no need to write a special shader for flat shading. What makes the difference is selecting either "Shade Flat" or "Shade Smooth" in Blender's Edit Mode as lunkhound mentioned, the shader works great for both.

You misunderstand; I'm just explaining why you got duplicated vertices when exporting with flat shading. There are several ways to achieve flat shading, and the way a mesh exported from Blender does it is to duplicate vertices, which is why switching to smooth shading reduces the number of vertices. You could write a shader to do it, which may be better in some situations, I'm not saying you should though, especially since it seems you actually want smooth shading!

[lunkhound]

Generally speaking, the vertices get bundled together with all of the different vertex attributes--normals, vertex colors, texture coordinates. So if any of the attributes differ between adjacent triangles, then additional vertices will be created as you observed.

With Blender you can't edit vertex normals directly, you can only flag faces as "shade smooth" or "shade flat" to tell blender how to generate vertex normals from the surrounding faces.

[vfraction]

Hi, I'm having a problem using the exported .mesh with InstancedGeometry: If I just use the exported .mesh directly, then only one instance appears per batch. But if I use OgreXMLConverter to generate the .mesh from the exported .xml, it works perfectly.

If I generate the .xml from the exported .mesh (using OgreXMLConverter), I get something extra from the exported .xml: another set of texture coordinates:

Exported .xml:

Code: Select all

  <mesh>
    <sharedgeometry vertexcount="54">
      <vertexbuffer colours_diffuse="False" normals="true" positions="true" texture_coords="1">
        <vertex>
          <position x="0.000000" y="0.635950" z="-1.965125"/>
          <normal x="-0.389284" y="-0.872742" z="-0.294583"/>
          <texcoord u="0.337059" v="0.254369"/>
        </vertex>
        ..

Generated .xml (using OgreXMLConverter on the exported .mesh):

Code: Select all

  <mesh>
    <sharedgeometry vertexcount="54">
      <vertexbuffer positions="true" normals="true" texture_coord_dimensions_0="float2" texture_coord_dimensions_1="float4" texture_coords="2">
        <vertex>
          <position x="0" y="0.63595" z="-1.96512" />
          <normal x="-0.389284" y="-0.872742" z="-0.294583" />
          <texcoord u="0.337059" v="0.254369" />
          <texcoord u="0.0163664" v="0.313206" w="-0.949544" x="-1" />
        </vertex>
        ..

Is there a setting in Blender I've missed? I'm using Blender 2.66 and the latest io_export_ogreDotScene.py from lunkhound.

[lunkhound]

I don't think this could be an issue with blender settings.
The exporter is also using OgreXMLConverter to generate the .mesh file, so I can only see 2 likely explanations for the difference you are seeing:

Either the version of OgreXMLConverter being invoked by the exporter is different from the one you used to convert the xml from.
Or if it isn't that, then the command line options given to OgreXMLConverter must be different.

There are some checkboxes in the exporter GUI that are used to determine the command line options for OgreXMLConverter. You could try changing some of those.

[vfraction]

Hi lunkhound, thanks for tip! I'll look into that.

[RigoCL]

Hi, I'm using the exporter version given here:

My updated version is here:
https://bitbucket.org/cc8192/blender2ogre

After using this exporter only for meshes, I'm experimenting again with animations, but I'm having problems when exporting a very simple animation of a Cube and an attached Bone. What I do is:

• Create a Cube.
  Create a Bone (armature -> single bone).
  Do Parenting using Control+P to the Cube+Bone, With Automatic Weights. This automatically creates a new Modifier and a new entrance in the Vertex Groups of the Cube.
  Do an Insert Keyframe based in current Location. This automatically creates a new entrance in the DopeSheet and in the NLA Editor.
  In the TimeLine I set a different keyframe and in the 3D View move the bone to some different position, which moves the Cube as well.
  Again, do an Insert Keyframe using new Location. This automatically adds a second keyframe in the DopeSheet and in the NLA Editor.
  Finally, I select the cube and do the export.

But I only get an almost empty skeleton file.

Code: Select all

<skeleton >
  <bones >
    <bone id="0" name="Bone" >
      <position x="-0.000000" y="0.000000" z="0.000000" />
      <rotation angle="0.000000" >
        <axis x="-0.000000" y="0.000000" z="0.000000" />
      </rotation>
    </bone>
  </bones>
  <bonehierarchy />
  <animations />
</skeleton>

I also tried clicking on the snowflake icon of the NLA Editor to create a NlaTrack, but no success. The "Armature Animation" is checked.

In fact, in the black window that pops up after exporting, I can see that only one ARMATURE is being exported, but no ARMATURE ANIMATIONS. So clearly that's the problem, the animation is not being exported.

What step am I missing?

PS: Using Blender 2.66.1

[lunkhound]

RigoCL,

I tried following the steps you listed, but it didn't reproduce the problem for me. I'm using a newer blender version (2.70a) but I've used 2.66 previously without problems (I think).
Can you share the .blend file?

[RigoCL]

RigoCL,

I tried following the steps you listed, but it didn't reproduce the problem for me. I'm using a newer blender version (2.70a) but I've used 2.66 previously without problems (I think).
Can you share the .blend file?

By saying "didn't reproduce the problem", you mean your exporting process actually exported the animation?

I used the exporter version mentioned in my last post, but now I used Blender 2.67, but having the same problem.

I'm attaching a zip with the .blend file, all the exported files and a screen capture of Blender right after the export process.

Thanks in advance.