[osg-users] Problem updating uniforms
Hi osg-users! I have a shader attached to a subgraph. The shader uses a uniform which needs to be updated in every frame. The uniform is related to the modelviewmatrix, and should thus get a different value for every node in the subgraph. I have tried to use a osg::Uniform::Callback, but the callback is only called for the parent node in the subgraph. I think it would work if I declare a uniform for each node, and attach an updating callback to each uniform, but there must be a more clever way do to it? Any help would be appreciated! Regards, Åsa Engvall ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Problem updating uniforms
Hi Asa, I was strongly recommend trying to use compute what you need from variables already available to your in the shader, do a per drawable binding of an uniform would awkward to implement and provide poor performance. Please note that you have gl_ModeViewMatrix and osg_ViewMatrix available in shaders as well a range of other variables. Robert. On Tue, Dec 2, 2008 at 1:47 PM, Engvall Åsa [EMAIL PROTECTED] wrote: Hi osg-users! I have a shader attached to a subgraph. The shader uses a uniform which needs to be updated in every frame. The uniform is related to the modelviewmatrix, and should thus get a different value for every node in the subgraph. I have tried to use a osg::Uniform::Callback, but the callback is only called for the parent node in the subgraph. I think it would work if I declare a uniform for each node, and attach an updating callback to each uniform, but there must be a more clever way do to it? Any help would be appreciated! Regards, Åsa Engvall ___ 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
Re: [osg-users] Problem updating uniforms
Hi Asa, Have a look at the osgParticle::PreciptionEffect as it caches the previous frames modelview matrix to enable it to compute motion blurr of the rain particles. This is done just for the precipitation effect drawables though. Robert. On Tue, Dec 2, 2008 at 2:08 PM, Engvall Åsa [EMAIL PROTECTED] wrote: I agree, but what I need in the shader is the modelViewMatrix from the previous frame. (By the way, it's for creating motion blur.) What would be the best way to accomplish this? Asa -Ursprungligt meddelande- Från: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] För Robert Osfield Skickat: den 2 december 2008 14:51 Till: OpenSceneGraph Users Ämne: Re: [osg-users] Problem updating uniforms Hi Asa, I was strongly recommend trying to use compute what you need from variables already available to your in the shader, do a per drawable binding of an uniform would awkward to implement and provide poor performance. Please note that you have gl_ModeViewMatrix and osg_ViewMatrix available in shaders as well a range of other variables. Robert. On Tue, Dec 2, 2008 at 1:47 PM, Engvall Åsa [EMAIL PROTECTED] wrote: Hi osg-users! I have a shader attached to a subgraph. The shader uses a uniform which needs to be updated in every frame. The uniform is related to the modelviewmatrix, and should thus get a different value for every node in the subgraph. I have tried to use a osg::Uniform::Callback, but the callback is only called for the parent node in the subgraph. I think it would work if I declare a uniform for each node, and attach an updating callback to each uniform, but there must be a more clever way do to it? Any help would be appreciated! Regards, Åsa Engvall ___ 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 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Problem updating uniforms
Thank you, I will do that! Asa -Ursprungligt meddelande- Från: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] För Robert Osfield Skickat: den 2 december 2008 15:15 Till: OpenSceneGraph Users Ämne: Re: [osg-users] Problem updating uniforms Hi Asa, Have a look at the osgParticle::PreciptionEffect as it caches the previous frames modelview matrix to enable it to compute motion blurr of the rain particles. This is done just for the precipitation effect drawables though. Robert. On Tue, Dec 2, 2008 at 2:08 PM, Engvall Åsa [EMAIL PROTECTED] wrote: I agree, but what I need in the shader is the modelViewMatrix from the previous frame. (By the way, it's for creating motion blur.) What would be the best way to accomplish this? Asa -Ursprungligt meddelande- Från: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] För Robert Osfield Skickat: den 2 december 2008 14:51 Till: OpenSceneGraph Users Ämne: Re: [osg-users] Problem updating uniforms Hi Asa, I was strongly recommend trying to use compute what you need from variables already available to your in the shader, do a per drawable binding of an uniform would awkward to implement and provide poor performance. Please note that you have gl_ModeViewMatrix and osg_ViewMatrix available in shaders as well a range of other variables. Robert. On Tue, Dec 2, 2008 at 1:47 PM, Engvall Åsa [EMAIL PROTECTED] wrote: Hi osg-users! I have a shader attached to a subgraph. The shader uses a uniform which needs to be updated in every frame. The uniform is related to the modelviewmatrix, and should thus get a different value for every node in the subgraph. I have tried to use a osg::Uniform::Callback, but the callback is only called for the parent node in the subgraph. I think it would work if I declare a uniform for each node, and attach an updating callback to each uniform, but there must be a more clever way do to it? Any help would be appreciated! Regards, Åsa Engvall ___ 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 ___ 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
