Hi Robert,
Thank you for your answer,
If shared vertex array are not common, it seems not necessary to support
them in IVE,
but in such case, maybe the DAE driver should not load meshes as shared
vertex array.
Maybe the best option is to update writers not supporting shared array :
Now, in those writers, for all geometries sharing an array, a deep copy of
the shared array is made for each geometry.
In writers not supporting shared arrays, geometries could keep only array
elements which are needed, rather than copying all the array.
According to you, what is the best option ?
Fabien
----- Original Message -----
From: "Robert Osfield" <[EMAIL PROTECTED]>
To: "OpenSceneGraph Users" <osg-users@lists.openscenegraph.org>
Sent: Tuesday, August 12, 2008 9:07 PM
Subject: Re: [osg-users] DAE to OSG/IVE conversion problem when vertex
areshared (OSG 2.4)
Hi Fabien,
I suspect there is a couple of issues here. First up .ive doesn't
support sharing of vertex arrays, it's not a particular common need
which is probably why no one else has highlighted this requirement or
step forward to implement. Adding won't be particularly difficult as
sharing of Nodes, Drawables and State is already supported, but it'll
require a increment of the ive version internal number/and careful
handling of backwards compatibility. Same applies to .osg. Feel free
to dive in and help implement it.
The other issue is that your .dae model is just 3Mb while the output
.ive is 250Mb, this screams to me that you have shared arrays in
separate geometry, whereas your model really should be setup as a
small number of geometry without shared arrays. I haven't had a
chance to look at your model - I have a full inbox so am just skimming
right now, but I'd suggest you have a look at how many primitives are
in each geometry.
Robert.
On Mon, Aug 11, 2008 at 11:48 AM, Fabien Dachicourt <[EMAIL PROTECTED]>
wrote:
Hi all,
Using osgconv on some DAE models to procude IVE files sometimes really
increase the vertex count (and file size)
I'm not talking about texture problem, but about geometry and vertex.
It seems the problem appear when vertex arrays are shared in the DAE
model
(in a mesh entity) between several geomerties using distinct materials.
When the DAE file is loaded in OSG, it seems ok, it looks like everything
remains shared.
But when we write the node (to IVE or OSG for instance, but it seems it
appears in other formats too), the shared vertex array seems duplicated
for
each geometry, including useless vertex : it dramatically increase the
object size (from 3 Mb to 250 Mb in my example).
Using "osgconv --simplify 1", we remove useless vertex and the problem is
almost solved.
Regarding this problem, I'm wondering if there is something to improve in
OGS :
- To support shared vertex arrays (and normals/textures arrays..) between
geodes in OSG or IVE format
- To remove any useless array element when writing nodes
See this example,
http://spaceyes.nerim.net/sample/sample_dae.zip
Thanks in advance for your answers,
Fabien
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
