Re: [osg-users] osgFX and RTT?
Ben, That sounds like exactly what I'm trying to do. I'd be interested in seeing how you set up the post effect class. Could you send me a link to the Delta3D thread? Rob. On Dec 19, 2007 11:00 PM, Ben Cain [EMAIL PROTECTED] wrote: Rob, I've written some classes that implement RTT and post-filtering using OSG and GLSL shaders. Let me know if interested. I thought about putting in Wiki when I get time. You can take the output of one RTT stage and apply it as an input to the next stage … ganging them together … allowing as many filters as needed ( e.g. for creating a night vision scene … RTT of main scene - color amplification stage - bright pass stage - horizontal Gauss blurring - vertical Gauss blurring - composition with original RTT of main stage - noise - change of resolution). The technique is from an idea of one of the users on Delta3D forum. Cheers, Ben -- *From:* [EMAIL PROTECTED] [mailto: [EMAIL PROTECTED] *On Behalf Of *Robert Hansford *Sent:* Wednesday, December 19, 2007 3:26 PM *To:* osg-users@lists.openscenegraph.org *Subject:* [osg-users] osgFX and RTT? Hi all, For one of the projects I'm working on I need to have several render passes which operate on the rendered scene as a texture. I was wondering if I could base the implementations on the osgFX::Effect class. I know the existing effects are all based around simply using different statesets, but would it be an inappropriate use of the Effect class to write Techniques which contain a render-to-texture camera and then operate on that texture? A few examples of the sort of thing I'm doing are as follows: 1) blurring the image using a Gaussian kernel. 2) computing the min and max pixel value in the image in order to downgrade HDR imagery to get the expected effects when an unusually bright object appears in the field of view. 3) adding noise to the image to simulate a poor quality camera. I am a little concerned that this may not be a proper use for the Effect class as this sort of process probably has to be done at the root of the scene graph, where as the existing effects can be applied to any subgraph. However, I do like the idea of implementing these processes as nodes in the graph that can be saved out to .osg files etc, but I can probably achieve this by writing my own class rather than extending Effect (though that would take me more time). I would greatly appreciate hearing people's thoughts on this matter. Thanks in advance, Rob. No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.17.5/1190 - Release Date: 12/19/2007 7:37 PM ___ 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] osgFX and RTT?
Robert, I guess that answers my question then. I was looking at osg::Effect as it seemed to have a lot in common with what I want to do, but you are right, its not really an appropriate use for it. Thanks Rob. On Dec 20, 2007 9:24 AM, Robert Osfield [EMAIL PROTECTED] wrote: Hi Rob, I don't see any reason why one would implement an osgFX::Effect using RTT. The idea of osgFX is that you decorate the subgraph that you want the effect on, this could be the whole scene, or just a single object. Robert. On Dec 19, 2007 9:25 PM, Robert Hansford [EMAIL PROTECTED] wrote: Hi all, For one of the projects I'm working on I need to have several render passes which operate on the rendered scene as a texture. I was wondering if I could base the implementations on the osgFX::Effect class. I know the existing effects are all based around simply using different statesets, but would it be an inappropriate use of the Effect class to write Techniques which contain a render-to-texture camera and then operate on that texture? A few examples of the sort of thing I'm doing are as follows: 1) blurring the image using a Gaussian kernel. 2) computing the min and max pixel value in the image in order to downgrade HDR imagery to get the expected effects when an unusually bright object appears in the field of view. 3) adding noise to the image to simulate a poor quality camera. I am a little concerned that this may not be a proper use for the Effect class as this sort of process probably has to be done at the root of the scene graph, where as the existing effects can be applied to any subgraph. However, I do like the idea of implementing these processes as nodes in the graph that can be saved out to .osg files etc, but I can probably achieve this by writing my own class rather than extending Effect (though that would take me more time). I would greatly appreciate hearing people's thoughts on this matter. Thanks in advance, Rob. ___ 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] osgFX and RTT?
Hi all, For one of the projects I'm working on I need to have several render passes which operate on the rendered scene as a texture. I was wondering if I could base the implementations on the osgFX::Effect class. I know the existing effects are all based around simply using different statesets, but would it be an inappropriate use of the Effect class to write Techniques which contain a render-to-texture camera and then operate on that texture? A few examples of the sort of thing I'm doing are as follows: 1) blurring the image using a Gaussian kernel. 2) computing the min and max pixel value in the image in order to downgrade HDR imagery to get the expected effects when an unusually bright object appears in the field of view. 3) adding noise to the image to simulate a poor quality camera. I am a little concerned that this may not be a proper use for the Effect class as this sort of process probably has to be done at the root of the scene graph, where as the existing effects can be applied to any subgraph. However, I do like the idea of implementing these processes as nodes in the graph that can be saved out to .osg files etc, but I can probably achieve this by writing my own class rather than extending Effect (though that would take me more time). I would greatly appreciate hearing people's thoughts on this matter. Thanks in advance, Rob. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] OSG and DIS
Hi all, Does anyone have any experience working with the DIS protocol ( http://en.wikipedia.org/wiki/Distributed_Interactive_Simulation) or something similar? I have to rewrite our OSG application to render a scene described/updated via DIS and I'm unsure of the best way to go about it (from a design point of view). DIS provides the state information for the various objects in the scene (eg their position, attitude and any degree-of-freedom or other attributes), so I will have to query that information before each frame is rendered. Presumably the best way to do that is to use the update callbacks for each object, but what resolution should I do it at? Should I have a single callback for each entity that updates all of it's data, or should each node in the graph callback to the appropriate datum? Either way, should I create classes that extend the existing OSG classes (eg a DIS-compatible PAT node, a DIS-compatible DoF node, a DIS-compatible LoD node etc) and then find some way to replace the appropriate instances of those nodes within the models? Or is there some other way to do it? I've never really looked at this side of OSG before. If anyone has done anything similar and wouldn't mind giving some advice, it would be greatly appreciated. Thanks in advance Rob. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] Setting window options
Hi all, I'm writing a little application which renders images to texture and passes them out to a Matlab program. So far it all works fine, but I was wondering if there is any way I can get rid of the window that appears when the application is running. It doesn't display anything as the only camera in the scene graph is set up for RTT, so its just a bit untidy. I'm running windows XP if that makes any difference. Thanks Rob. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] OSG and Threads
Hi all, I'm in the process of redesigning our OSG application (the current version is little better than a proof-of-principle prototype, and wasn't written by me) and I'm trying to sort out how the threads will interact. The application has to render imagery from one or more views of a common scene which is updated via a network connection. The rendered imagery will probably need to be delivered back over the network, either by reading back each frame or by using a separate video capture card. My current plan is to have a thread which interacts with the network and converts the packets into updates to the scene graph, then have a second thread which does the rendering, and possibly a third thread to readback and compress the imagery (though this may be done separately via a video capture card). I am also considering a fourth thread to do the scene management stuff, like applying updates from the network and loading models in the background, but I'm not sure how necessary this is. So my questions are as follows: Is my architecture sensible? - Is there a 'better' way to do it? - How closely should I integrate my application with OSG? From a design point of view I'm tempted to create lots of adapters or facades (ie do it properly), but as I will also be the one doing the implementation I'm not sure I can be bothered. How easy is it use OSG in a multi-threaded environment? - Do I need to provide my own mutual exclusion code when modifying the scene graph or is it already taken care of? I think I will need each of the viewpoints to be rendered to a separate window, what is the best mechanism for doing this? - Each view should use the same scene graph except they will each have a different set of render passes and some different shaders and uniforms, is this achievable, and how? - Will each view need to run in a separate thread, or can they all run in one thread? Are there performance implications either way? Thanks in advance for any help. Rob. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
