Re: [Maya2osg-users] Blend shapes

[Peter W. <pp...@cg...>]

Hi Javier, and thanks for understanding.

Just one questin, how urgent is it at all ?

Cheers, PP


>    Hi Peter,
>
> On Thu, May 19, 2011 at 10:50 AM, Peter Wrobel<pp...@cg...>  wrote:
>> Hi Javier,
>>
>> fast answer, but details on mondy.
>    OK. Don't worry just ignore the messages if you're busy. We'll
> follow the thread next week.
>
>>>     I'm going to export a 3D character with skeleton animation and blend
>>> shapes, so I will at last test the osgAnimation export  :)
>> I wasn't able to add Skinning Code till now, so all yo can export is
>> transform animation. My osgMaya exporter has skinning implemented, but
>> the merging will take some time, so I don't know how fast I'll get to this.
>    OK. Maybe I can help with it. I'll take a look at it when I had some time.
>
>>>     Are blend shapes supported in Maya2OSG? Is there any development? Or
>>> may I have to start from scratch?
>> I started to write the export for that. I stopped as I was a little
>> frustrated that you cannot't "chain" the skining and morphing in an osg
>> file. Cedric showed me how to do this through code. But now I already
>> know more about osg, and I have an Idea what has to be done.
>> Datails after monday
>    OK. We'll follow the discussion next week.
>
>>>     And about how to prepare the model, it is a pseudo-humanoid
>>> character (biped) that will have blend shapes applied only to the
>>> face. The artist is asking me whether she should cut out the head to
>>> create the blend shapes only there or keep the body geometry as a
>>> whole. Is it a problem to rejoin the blend-shaped head later with the
>>> rest of the body? Have you ever done it?
>> This is the "normal" way people do it in the industry. So for the
>> begining it would be cool if she would keep the whole body mesh
>> attached. Later we should add this functionality, but I don't know how
>> far osgANimation needs to support this. Basically in normal morphing you
>> blend the position of a point to the position of another point. You
>> identify both points with their id. If you screw up point numbering in
>> one of the meshes ( by deliting one Vertex somwhere ) you scre up the
>> morphing. We would require a map between target and source ids. That we
>> can do in the plug in, but can osgAnimation use such a map ? Not shure,
>> but I don't think so.
>    Yes, I know the blend shape theory. I didn't know however how much
> is it supported in osgAnimation.
>
>>>     In case of having the "blend-shaped head" and the body in separate
>>> geometries, both affected by the skeleton animation, as long as the
>>> vertices in the joint edges are not affected by blend shapes and have
>>> assigned the exact same weights in skinning, should it be a problem?
>>> Do you think it would produce visible cracks in this part of the
>>> geometry?
>> No, the way you normally di it is, cut the hayd off, but dont' morph the
>> border edges. With this you guarantee continuity.
>    Yes, that's exactly what I meant. My doubt was, being the geometry
> split in two pieces, even though the vertices are in the same place if
> there are any problems of edge cracks. I hope not.
>
>