Well, the shader doesn't "know" of the stateset of the object (textures attached) if you don't set it explicitly. Otherwise, the shader can be inherited and at ObjectX you can add a uniform for the sampler.
You are right that all the objects will be rendered with the same shader. If you set different shader for each object, I would like some clarification about your original question. Do you want different shader per object but with some common features that are different for each view?? If so, keep the shader as they were (differently setted) on the objects in the single view. Add to all the shaders uniforms for the "View" properties, and set the uniforms values differently at each View node. Hope it helps, Guy. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Christian Heine Sent: Tuesday, April 08, 2008 5:39 PM To: OpenSceneGraph Users Subject: Re: [osg-users] Dilemma with the usage of object Shaders in differend views ... Hello Guy, >I think attaching a shader to each view instead of to object X would be >fine. I'm not sure if this may be the right thing. Correct me if I'm wrong but this causes in some other issues: 1. I lost the reference to the specifiv object states like Textures, Geometries etc. How does the shader should access this values by differend objects? 2. If i bind it to the view, each object is rendered with this shader. So i shouldn't have the ability to separate shaders and effects between objects ... >If you want to use the callback I think you should create a pre-draw >callback to the object, which I'm not sure possible. The update >callbacks won't help you since it run on all the scene before the >rendering and then only the last setting of the shader will be set, and >it also might affect performance. So I still think attaching shaders to >the views would do what you want. Ok, this is an argument i've to agree. But if If i overload the render method of the composite viewer i could implement "callbacks" (better update sequences) for each object before calling the parent rendering method, so this should be possible. But i am not sure about possible perfomance lacks ... Best regards, Chrsitian Guy wrote: > Hello, > I think attaching a shader to each view instead of to object X would be > fine. > If you want to use the callback I think you should create a pre-draw > callback to the object, which I'm not sure possible. The update > callbacks won't help you since it run on all the scene before the > rendering and then only the last setting of the shader will be set, and > it also might affect performance. So I still think attaching shaders to > the views would do what you want. > > Guy. > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > [EMAIL PROTECTED] > Sent: Tuesday, April 08, 2008 10:55 AM > To: osg-users@lists.openscenegraph.org > Subject: [osg-users] Dilemma with the usage of object Shaders in > differend views ... > > Hi folks, > > actually i am working on object shading with OSG (i.e. Dot3). All works > fine > with single views. Now i am using the osgViewer::Composite viewer and > getting > some dielemma with the usage of object based shaders in differend views > based > on the same scene graph. > > I.e.: I've a single scene node with an object X where i bind the shaders > (at > the object StateSet) for execution. In a single view no problem. If i > use this scene in > multiple views (i.e. A, B) i've the dilemma, that i've to use diffrend > shader params > on the same shader instance. In each rendering pass the params of the > camera > are differend from the point of view of the views, if the views are > rendered. But > the shader has no knowledge about this, it uses only a single uniform to > hook bind > param ... > > I've thought about the following sollutions: > > 1. Using for each view a single shader instance at the same object > StateSet. > Is this usefull? If the scene is complex i could get a huge count of > shaders > which have to be executed. Additionally i'm not sure, if the binding of > the "unused" > shaders produces render artifacts or perfomance issues... > > 2. Using a callback mechanism which switches this values at the shader > before > rendering > > How i could achieve this aim in best way? Has anyone a better solution? > > Best regards, > Christian > > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or > g > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g > > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
