[osg-users] painting plane

Tomlinson, Gordon GTOMLINSON at overwatch.textron.com
Thu Sep 11 06:28:54 PDT 2008


 
Doubtful really as lines don't have back faces..

Gordon

__________________________________________________________
Gordon Tomlinson
Email  : gtomlinson @ overwatch.textron.com


-----Original Message-----
From: osg-users-bounces at lists.openscenegraph.org [mailto:osg-users-bounces at lists.openscenegraph.org] On Behalf Of Korolyov Ilia
Sent: Thursday, September 11, 2008 9:20 AM
To: OpenSceneGraph Users
Subject: Re: [osg-users] painting plane

Hello

This technic working fine for poligons, but is it possible to make this trick to lines? I need exactly two lines, not three as in triangle.

I trying in such way

group->addChild( geode_with_poligons );
group->addChild( geode_with_lines );
group->getOrCreateStateSet()->setMode( GL_CULL_FACE, GL_BACK |
osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON );

Thanks
Ilia

В Чтв, 11/09/2008 в 14:46 +0400, Korolyov Ilia пишет:
> Hello, Robert
> 
> Thanks so much - it really helps
> 
> Ilia
> 
> В Чтв, 11/09/2008 в 11:38 +0100, Robert Osfield пишет:
> > Hi Ilia,
> > 
> > If one side of the plane should be red, and the other blue then you 
> > could render two polygons for the plane, each with opposite winding 
> > and colour, then use glCullFace(osg::CullFace) to cull the faces to 
> > give the illusion of changing colour.  The other technique you could 
> > use of two sided colour in the OpenGL lighting/material model, not 
> > all hardware/drivers supports two side lighting though.
> > 
> > Robert.
> > 
> > On Thu, Sep 11, 2008 at 11:22 AM, Korolyov Ilia <ya-breeze at ya.ru> wrote:
> > > Hello
> > >
> > > I need to draw a plane (more exactly two lines by three points). 
> > > Problem is in plane color. It must depends on camera position 
> > > relative plane side - red or blue.
> > >
> > > I did it with CullCallback, because it's only one way to get 
> > > access to camera, which I can find.
> > >
> > > What is right way to do it?
> > >
> > > Thanks
> > > Ilia
> > >
> > > _______________________________________________
> > > osg-users mailing list
> > > osg-users at lists.openscenegraph.org
> > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegr
> > > aph.org
> > >
> > _______________________________________________
> > osg-users mailing list
> > osg-users at lists.openscenegraph.org
> > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegrap
> > h.org
> 
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.
> org

_______________________________________________
osg-users mailing list
osg-users at lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org



More information about the osg-users mailing list