Re: [osg-users] Shadow mapping, multiple lights
Hi Mustafa, The ViewDepedentShadowMap implementation has the beginnings of multiple light support but it isn't yet complete. The basic infrastructure for generating multiple shadow map texture is there, but the final bits that tie together like shaders and management aren't there yet. Robert. On 6 November 2013 20:11, Mustafa Kabak mustafa_ka...@gmx.com wrote: Hi, Does any shadow mapping technique in osgShadow support multiple lights? I have seen some commit logs and list messages hinting at this functionality, but no solid information. http://osdir.com/ml/osg-users/2011-08/msg00413.html http://trac.openscenegraph.org/projects/osg//changeset/12782/OpenSceneGraph/trunk/include/osgShadow/ViewDependentShadowMap Simply putting two LightSources in the scene with ViewDependentShadowMap didn't help. Thanks, -- Mustafa Kabak ___ 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] OSG Qt integration and thread safety
Hi Jan, Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. On Wed, Nov 6, 2013 at 9:19 PM, Jan Ciger jan.ci...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Deniz, On 11/06/2013 07:07 PM, Deniz Koçak wrote: This is already a long mail, still I have more to say, many code to post, but I am not sure where should I begin. I can provide as much as possible. However, before ending my e-mail, I would like to ask if this approach is safe or not? I mean, I call frame() method within a Qt slot and again update related datas within another Qt slot. Qt has a main loop (GUI thread) of course, and is it possible to cause a race-condition with OSG, because it has its own threading model? Please ask if you need more information and of course you will, I would be glad to tell more. Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. If your GUI is modifying the vertex array from the Qt slot, that is, by definition, asynchronous - you have no idea when the user presses that button. Which may well be during the rendering when OSG is using that data structure. If you are clearing the vertex array while the size of the array is still set, it will go boom. One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). Regards, J. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iD8DBQFSeqRWn11XseNj94gRAuBdAKDuE2rxjaXltXEWg4g2Mka1ZBqVIgCfbKju vGG9MllrwxlDZjkUd1HHg+8= =S3At -END PGP SIGNATURE- ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- trajce nikolov nick ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] OSG Qt integration and thread safety
Hi Jan, You can modify the scenegraph in the update traversal as well. Like I did in the TerraPage (txp) loader. In the Cull traversall I collect info for what is to be modified and then in the update traversal I update the scenegraph safely. Just a note Nick On Thu, Nov 7, 2013 at 9:33 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. On Wed, Nov 6, 2013 at 9:19 PM, Jan Ciger jan.ci...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Deniz, On 11/06/2013 07:07 PM, Deniz Koçak wrote: This is already a long mail, still I have more to say, many code to post, but I am not sure where should I begin. I can provide as much as possible. However, before ending my e-mail, I would like to ask if this approach is safe or not? I mean, I call frame() method within a Qt slot and again update related datas within another Qt slot. Qt has a main loop (GUI thread) of course, and is it possible to cause a race-condition with OSG, because it has its own threading model? Please ask if you need more information and of course you will, I would be glad to tell more. Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. If your GUI is modifying the vertex array from the Qt slot, that is, by definition, asynchronous - you have no idea when the user presses that button. Which may well be during the rendering when OSG is using that data structure. If you are clearing the vertex array while the size of the array is still set, it will go boom. One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). Regards, J. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iD8DBQFSeqRWn11XseNj94gRAuBdAKDuE2rxjaXltXEWg4g2Mka1ZBqVIgCfbKju vGG9MllrwxlDZjkUd1HHg+8= =S3At -END PGP SIGNATURE- ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- trajce nikolov nick -- trajce nikolov nick ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] OSG Qt integration and thread safety
Hi Trajce, I think Jan's answer [1] in the first mail mentions a similar solution. Setting a flag (by using userdata of the drawable may be) and updating the drawable in the osg::Drawable::UpdateCallback (of course by checking the flag) MAY solve the problem. It seems that, thrusting the Qt's Signal/Slot mechanism is not a good option as Jan pointed. Cheers, Deniz [1] One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). On Thu, Nov 7, 2013 at 10:35 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, You can modify the scenegraph in the update traversal as well. Like I did in the TerraPage (txp) loader. In the Cull traversall I collect info for what is to be modified and then in the update traversal I update the scenegraph safely. Just a note Nick On Thu, Nov 7, 2013 at 9:33 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. On Wed, Nov 6, 2013 at 9:19 PM, Jan Ciger jan.ci...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Deniz, On 11/06/2013 07:07 PM, Deniz Koçak wrote: This is already a long mail, still I have more to say, many code to post, but I am not sure where should I begin. I can provide as much as possible. However, before ending my e-mail, I would like to ask if this approach is safe or not? I mean, I call frame() method within a Qt slot and again update related datas within another Qt slot. Qt has a main loop (GUI thread) of course, and is it possible to cause a race-condition with OSG, because it has its own threading model? Please ask if you need more information and of course you will, I would be glad to tell more. Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. If your GUI is modifying the vertex array from the Qt slot, that is, by definition, asynchronous - you have no idea when the user presses that button. Which may well be during the rendering when OSG is using that data structure. If you are clearing the vertex array while the size of the array is still set, it will go boom. One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). Regards, J. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iD8DBQFSeqRWn11XseNj94gRAuBdAKDuE2rxjaXltXEWg4g2Mka1ZBqVIgCfbKju vGG9MllrwxlDZjkUd1HHg+8= =S3At -END PGP SIGNATURE- ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- trajce nikolov nick -- trajce nikolov nick ___ 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] OSG Qt integration and thread safety
Hi Deniz, yes I read Jan has mentioned this. Have a look in the osgdb_txp loader in TXPNode::traverse() for inspiration if helps a bit Nick On Thu, Nov 7, 2013 at 9:40 AM, Deniz Koçak lend...@gmail.com wrote: Hi Trajce, I think Jan's answer [1] in the first mail mentions a similar solution. Setting a flag (by using userdata of the drawable may be) and updating the drawable in the osg::Drawable::UpdateCallback (of course by checking the flag) MAY solve the problem. It seems that, thrusting the Qt's Signal/Slot mechanism is not a good option as Jan pointed. Cheers, Deniz [1] One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). On Thu, Nov 7, 2013 at 10:35 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, You can modify the scenegraph in the update traversal as well. Like I did in the TerraPage (txp) loader. In the Cull traversall I collect info for what is to be modified and then in the update traversal I update the scenegraph safely. Just a note Nick On Thu, Nov 7, 2013 at 9:33 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. On Wed, Nov 6, 2013 at 9:19 PM, Jan Ciger jan.ci...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Deniz, On 11/06/2013 07:07 PM, Deniz Koçak wrote: This is already a long mail, still I have more to say, many code to post, but I am not sure where should I begin. I can provide as much as possible. However, before ending my e-mail, I would like to ask if this approach is safe or not? I mean, I call frame() method within a Qt slot and again update related datas within another Qt slot. Qt has a main loop (GUI thread) of course, and is it possible to cause a race-condition with OSG, because it has its own threading model? Please ask if you need more information and of course you will, I would be glad to tell more. Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. If your GUI is modifying the vertex array from the Qt slot, that is, by definition, asynchronous - you have no idea when the user presses that button. Which may well be during the rendering when OSG is using that data structure. If you are clearing the vertex array while the size of the array is still set, it will go boom. One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). Regards, J. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iD8DBQFSeqRWn11XseNj94gRAuBdAKDuE2rxjaXltXEWg4g2Mka1ZBqVIgCfbKju vGG9MllrwxlDZjkUd1HHg+8= =S3At -END PGP SIGNATURE- ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- trajce nikolov nick -- trajce nikolov nick ___ 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 -- trajce nikolov nick ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] OSG Qt integration and thread safety
Thank you Trajce. On Thu, Nov 7, 2013 at 10:59 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Deniz, yes I read Jan has mentioned this. Have a look in the osgdb_txp loader in TXPNode::traverse() for inspiration if helps a bit Nick On Thu, Nov 7, 2013 at 9:40 AM, Deniz Koçak lend...@gmail.com wrote: Hi Trajce, I think Jan's answer [1] in the first mail mentions a similar solution. Setting a flag (by using userdata of the drawable may be) and updating the drawable in the osg::Drawable::UpdateCallback (of course by checking the flag) MAY solve the problem. It seems that, thrusting the Qt's Signal/Slot mechanism is not a good option as Jan pointed. Cheers, Deniz [1] One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). On Thu, Nov 7, 2013 at 10:35 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, You can modify the scenegraph in the update traversal as well. Like I did in the TerraPage (txp) loader. In the Cull traversall I collect info for what is to be modified and then in the update traversal I update the scenegraph safely. Just a note Nick On Thu, Nov 7, 2013 at 9:33 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: Hi Jan, Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. On Wed, Nov 6, 2013 at 9:19 PM, Jan Ciger jan.ci...@gmail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Deniz, On 11/06/2013 07:07 PM, Deniz Koçak wrote: This is already a long mail, still I have more to say, many code to post, but I am not sure where should I begin. I can provide as much as possible. However, before ending my e-mail, I would like to ask if this approach is safe or not? I mean, I call frame() method within a Qt slot and again update related datas within another Qt slot. Qt has a main loop (GUI thread) of course, and is it possible to cause a race-condition with OSG, because it has its own threading model? Please ask if you need more information and of course you will, I would be glad to tell more. Your approach isn't safe. OSG is *not threadsafe*. Or, rather, it is not threadsafe from arbitrary modifications. If you want to be safe, the only time when modifications to the scene graph may happen is before or after the frame() is invoked, not while frame() is running. If your GUI is modifying the vertex array from the Qt slot, that is, by definition, asynchronous - you have no idea when the user presses that button. Which may well be during the rendering when OSG is using that data structure. If you are clearing the vertex array while the size of the array is still set, it will go boom. One way to solve this is to use the slot to only modify a buffer/set a flag and then use e.g. an update callback on the affected OSG node to pick up the changes and implement them in the scene graph when it is safe (during update traversal). Regards, J. -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iD8DBQFSeqRWn11XseNj94gRAuBdAKDuE2rxjaXltXEWg4g2Mka1ZBqVIgCfbKju vGG9MllrwxlDZjkUd1HHg+8= =S3At -END PGP SIGNATURE- ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- trajce nikolov nick -- trajce nikolov nick ___ 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 -- trajce nikolov nick ___ 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] Is it possible to use EffectCompositor to describe effects per object?
Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ 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] OSG Qt integration and thread safety
Hi, On Thu, Nov 7, 2013 at 9:35 AM, Trajce Nikolov NICK trajce.nikolov.n...@gmail.com wrote: You can modify the scenegraph in the update traversal as well. Like I did in the TerraPage (txp) loader. In the Cull traversall I collect info for what is to be modified and then in the update traversal I update the scenegraph safely. Thanks for the correction, you are right, of course - I was actually suggesting the same in my earlier mails. J. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] OSG Qt integration and thread safety
On Thu, Nov 7, 2013 at 9:40 AM, Deniz Koçak lend...@gmail.com wrote: It seems that, thrusting the Qt's Signal/Slot mechanism is not a good option as Jan pointed. I think the trouble is that you are expecting it to do something that it isn't meant to do. Perhaps you have confused the synchronous call with the idea of synchronized call from Java. In Java it does actually mean mutual exclusion on the object and with that semantics your code would have worked. In C++ you could implement something similar with an object-level lock shared between all synchronized slots, but I think the performance would be better if you use the buffer and the callback instead - the buffer would be locked for a much shorter time (callback invocation vs. the entire rendering time), decoupling the rendering and GUI. J. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Drawing lines using OpenGL ES 2.0
Hi, you are outputting the position as color, that's why you see black (because these have negative coordinate values) and the three values. Just set an arbitrary fixed color value in the frag-shader to see anything. But if you need to see colors, then you need to define your own vertex attribute for passing in colors. But my advice is that you should first get used to writing very basic shaders in opengl 3.0 core profile mode. OpenGL ES 2.0 is similar in the sense they do not support fixed function pipeline. You need to learn the basics first. -deniz -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=57108#57108 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Is it possible to use EffectCompositor to describe effects per object?
Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com mailto:wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto:osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto: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] Is it possible to use EffectCompositor to describe effects per object?
Hi, Sebastian. So you compose one shader per object? Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ 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 listosg-users@lists.openscenegraph.orghttp://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] Is it possible to use EffectCompositor to describe effects per object?
Am 07.11.2013 12:55, schrieb michael kapelko: Hi, Sebastian. So you compose one shader per object? No, one program per define-set (e.g. #define NORMAL_MAPPING,#define PARALLAX_MAPPING, ...) The idea is not to compose the shader from functional blocks, but to write one shader containing all paths which are activated based upon the defines. It is still complicated to get all the paths correctly in the ubershader, but i found it a good transition from uniform based de/activation. So you will end up with N different programs with N being the number of define-combinations used. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com mailto:wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto:osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto:osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto:osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org mailto: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] Is it possible to use EffectCompositor to describe effects per object?
Can you please provide an example of how an object manages its define-set? In my case, I simply get the object's StateSet and setup uniforms. But I don't get how to setup defines. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de Am 07.11.2013 12:55, schrieb michael kapelko: Hi, Sebastian. So you compose one shader per object? No, one program per define-set (e.g. #define NORMAL_MAPPING,#define PARALLAX_MAPPING, ...) The idea is not to compose the shader from functional blocks, but to write one shader containing all paths which are activated based upon the defines. It is still complicated to get all the paths correctly in the ubershader, but i found it a good transition from uniform based de/activation. So you will end up with N different programs with N being the number of define-combinations used. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ 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 listosg-users@lists.openscenegraph.orghttp://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 listosg-users@lists.openscenegraph.orghttp://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] Is it possible to use EffectCompositor to describe effects per object?
As this is company code and part of a bigger framework I can only give you some hints. I have a custom shader loader which parses the shader source in order to later add the defines and creates a osg::Program derived class e.g. CustomProgram. In GLSL you can use preprocessor macros like in C. So you can say: #define PATH_1 and later vec4 color = vec4(); #ifdef PATH_1 color = vec4(1,0,0,0); #else color = vec4(0,0,1,0); #endif So the shader loader will create the CustomProgram which holds a list of defines which should be applied later. The CustomProgram itself will do this in the ::apply function, by injecting the #define %DEFINE_NAME% in to the shadersource before compiling it. For setting the defines at the statesets you want, you can simply check the stateset for a program-attribute, cast it to CustomShader and add a define. You will have to do some management inside the CustomProgram to make it aware of changed define-sets etc. But it the end you are simply adding some custom attributes to control the compiled shader program at the state set, instead of setting uniforms directly. While this seems complicated it allows for two things: 1. Fast less-branching shader code 2. Different sets of shaders realizing rendering based upon defines. In my case I can do deferred and forward shading with the same framework without having to know which one is running under the hood, when assigning materials/material effects. cheers Sebastian Can you please provide an example of how an object manages its define-set? In my case, I simply get the object's StateSet and setup uniforms. But I don't get how to setup defines. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de Am 07.11.2013 12:55, schrieb michael kapelko: Hi, Sebastian. So you compose one shader per object? No, one program per define-set (e.g. #define NORMAL_MAPPING,#define PARALLAX_MAPPING, ...) The idea is not to compose the shader from functional blocks, but to write one shader containing all paths which are activated based upon the defines. It is still complicated to get all the paths correctly in the ubershader, but i found it a good transition from uniform based de/activation. So you will end up with N different programs with N being the number of define-combinations used. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com mailto:wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object.
Re: [osg-users] Is it possible to use EffectCompositor to describe effects per object?
I was thinking of creating some sort of material.xml and assign it to each object (or a group of objects). As far as I understand, the define approach creates one shader per object eventually. And that turns out to be faster than one shader per pipeline with different StateSets and uniforms per object. Am I correct? Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de As this is company code and part of a bigger framework I can only give you some hints. I have a custom shader loader which parses the shader source in order to later add the defines and creates a osg::Program derived class e.g. CustomProgram. In GLSL you can use preprocessor macros like in C. So you can say: #define PATH_1 and later vec4 color = vec4(); #ifdef PATH_1 color = vec4(1,0,0,0); #else color = vec4(0,0,1,0); #endif So the shader loader will create the CustomProgram which holds a list of defines which should be applied later. The CustomProgram itself will do this in the ::apply function, by injecting the #define %DEFINE_NAME% in to the shadersource before compiling it. For setting the defines at the statesets you want, you can simply check the stateset for a program-attribute, cast it to CustomShader and add a define. You will have to do some management inside the CustomProgram to make it aware of changed define-sets etc. But it the end you are simply adding some custom attributes to control the compiled shader program at the state set, instead of setting uniforms directly. While this seems complicated it allows for two things: 1. Fast less-branching shader code 2. Different sets of shaders realizing rendering based upon defines. In my case I can do deferred and forward shading with the same framework without having to know which one is running under the hood, when assigning materials/material effects. cheers Sebastian Can you please provide an example of how an object manages its define-set? In my case, I simply get the object's StateSet and setup uniforms. But I don't get how to setup defines. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de Am 07.11.2013 12:55, schrieb michael kapelko: Hi, Sebastian. So you compose one shader per object? No, one program per define-set (e.g. #define NORMAL_MAPPING,#define PARALLAX_MAPPING, ...) The idea is not to compose the shader from functional blocks, but to write one shader containing all paths which are activated based upon the defines. It is still complicated to get all the paths correctly in the ubershader, but i found it a good transition from uniform based de/activation. So you will end up with N different programs with N being the number of define-combinations used. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph to a camera binding to a FBO, and then uses RTT cameras to perform the post processing work. The last step is always to show the final image on an HUD quad so all other scene nodes will be occluded. The only way to make the effect compositor work with other fixed pipeline nodes is to write to the depth values in the shader code of the last step, which cannot be automated. The dof.xml does such work so you may try ./osgeffectcompositor --normal-scene cessna.osg --effect dof.xml to see how normal and deferred shaded objects are merged. At present I haven't had a better idea about this problem. :-) Wang Rui 2013/10/30 michael kapelko korn...@gmail.com Hi. I've recently implemented deferred shading with normal mapping and shadow mapping using EffectCompositor, but it has effect on the whole scene, not a single object. Is it possible to use EffectCompositor to apply effects per object? Thanks. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list
Re: [osg-users] Is it possible to use EffectCompositor to describe effects per object?
Am 07.11.2013 14:04, schrieb michael kapelko: I was thinking of creating some sort of material.xml and assign it to each object (or a group of objects). You could totally do this. So material.xml could contain the defines. As far as I understand, the define approach creates one shader per object eventually. And that turns out to be faster than one shader per pipeline with different StateSets and uniforms per object. Am I correct? Partially. It eventually creates one shader program per node. There might be different statesets after all. As the shader-program is part of the StateSet. The thing saved here are the uniforms (in my case there where around 50 non-material/camera related uniforms just for controlling which rendering-paths are taken) Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de As this is company code and part of a bigger framework I can only give you some hints. I have a custom shader loader which parses the shader source in order to later add the defines and creates a osg::Program derived class e.g. CustomProgram. In GLSL you can use preprocessor macros like in C. So you can say: #define PATH_1 and later vec4 color = vec4(); #ifdef PATH_1 color = vec4(1,0,0,0); #else color = vec4(0,0,1,0); #endif So the shader loader will create the CustomProgram which holds a list of defines which should be applied later. The CustomProgram itself will do this in the ::apply function, by injecting the #define %DEFINE_NAME% in to the shadersource before compiling it. For setting the defines at the statesets you want, you can simply check the stateset for a program-attribute, cast it to CustomShader and add a define. You will have to do some management inside the CustomProgram to make it aware of changed define-sets etc. But it the end you are simply adding some custom attributes to control the compiled shader program at the state set, instead of setting uniforms directly. While this seems complicated it allows for two things: 1. Fast less-branching shader code 2. Different sets of shaders realizing rendering based upon defines. In my case I can do deferred and forward shading with the same framework without having to know which one is running under the hood, when assigning materials/material effects. cheers Sebastian Can you please provide an example of how an object manages its define-set? In my case, I simply get the object's StateSet and setup uniforms. But I don't get how to setup defines. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de Am 07.11.2013 12:55, schrieb michael kapelko: Hi, Sebastian. So you compose one shader per object? No, one program per define-set (e.g. #define NORMAL_MAPPING,#define PARALLAX_MAPPING, ...) The idea is not to compose the shader from functional blocks, but to write one shader containing all paths which are activated based upon the defines. It is still complicated to get all the paths correctly in the ubershader, but i found it a good transition from uniform based de/activation. So you will end up with N different programs with N being the number of define-combinations used. Thanks. 2013/11/7 Sebastian Messerschmidt sebastian.messerschm...@gmx.de mailto:sebastian.messerschm...@gmx.de Hi Michael, I solved a similar problem by overriding osg::Program which composes a shader from an Ubershader. This is not done via uniforms but defines. It seems to work somehow and improved the performance over branching based on uniforms. Hi. I decided to go with single pipeline that provides big shaders and objects using own uniforms and textures to change the pipeline behaviour. I started to design a simple material format so that it resembles the one of EffectCompositor. Thanks. 2013/10/31 michael kapelko korn...@gmail.com mailto:korn...@gmail.com Hi, Wang. I've just checked if I can use some uber shader and control its behaviour per object by setting the object's uniforms. And it works. I wonder if that's ok to do that to make different objects rendered differently in the same scene. Thanks. 2013/10/31 Wang Rui wangra...@gmail.com mailto:wangra...@gmail.com Hi Michael, Effect compositor in fact adds the child scene graph
Re: [osg-users] Drawing lines using OpenGL ES 2.0
Actually I solved it... one of the problems was that the number I was using for
the attribute was too big (or reserved).
I am forced to use OpenGL ES 2.0 because I develop on iOS platform!
Thank you anyway for your advice.
Cheers,
John
This is the working code
Code:
#define BARYCENTRIC_ATTR_UNIT 11
void OSGGraphicsUtils::setBarycentricCoordinates(osg::Node * object,
osg::Program *shaderProgram)
{
GeodeFinder myGeodeFinder;
std::vector osg::Geode * listOfGeodes;
object-accept(myGeodeFinder);
listOfGeodes = myGeodeFinder.getNodeList();
std::cout there are listOfGeodes.size() geodes std::endl;
for (int j = 0; j listOfGeodes.size() ; j++)
{
//play with the Geode here
std::cout Geode number j std::endl;
//get the current geode
osg::Geode* currentGeode = listOfGeodes.at(j);
if (currentGeode != NULL)
{
std::cout number of drawables in geode is
currentGeode-getNumDrawables() std::endl;
for (int i = 0; i currentGeode-getNumDrawables(); i++)
{
std::cout current geode class is
currentGeode-getDrawable(i)-className() std::endl;
std::cout inside cycle i std::endl;
osg::Geometry *cubeGeometry =
currentGeode-getDrawable(i)-asGeometry();
if (!cubeGeometry) continue;
int numAttribs =
cubeGeometry-getVertexArray()-getNumElements();
std::cout number of vertices is numAttribsstd::endl;
osg::ref_ptr osg::Vec3Array cubeVertexVector;
if (! strcmp (cubeGeometry-getVertexArray()-className(),
Vec3Array))
{
cubeVertexVector = (osg::Vec3Array *)
cubeGeometry-getVertexArray();
} else {
//handle the error however you want -- here all I do is
print a warning and bail out.
std::cerr Unexpected VertexArray className.\n
std::endl;
return;
}
osg::ref_ptrosg::Vec3Array array = new osg::Vec3Array;
//add this to declaration section:
std::map int, int vertexMap;
osg::ref_ptr osg::PrimitiveSet nextPrimitiveSet;
// ... //
int k = 0;
for (i = 0; i cubeGeometry-getNumPrimitiveSets(); i++) {
nextPrimitiveSet = cubeGeometry-getPrimitiveSet(i);
//cout PrimitiveSet # i has Mode:
nextPrimitiveSet-getMode() endl;
//cout \tVertex Indices: endl;
for (j = 0; j nextPrimitiveSet-getNumIndices(); j++)
{
if(vertexMap.find(nextPrimitiveSet-index(j)) ==
vertexMap.end())
{
if (k==3) k = 0;
//cout \t nextPrimitiveSet-index(j)
endl;
vertexMap[nextPrimitiveSet-index(j)] = k;
k++;
}
else
{
k = vertexMap[nextPrimitiveSet-index(j)] + 1;
}
}
}
for (int i = 0; i numAttribs; i++) {
int j = vertexMap[i];
if (j==0)
{
array-push_back(osg::Vec3f(1.0f,0.0f,0.0f));
}
else if (j==1)
{
array-push_back(osg::Vec3f(0.0f,1.0f,0.0f));
}
else if (j==2)
{
array-push_back(osg::Vec3f(0.0f,0.0f,1.0f));
}
//std::cout Vertex # i : (
cubeVertexVector-getName()): ( nextVertex[0] , nextVertex[1]
, nextVertex[2] )\n;
}
std::cout Array size is array-getNumElements()
std::endl;
if( !cubeGeometry-getVertexAttribArray( BARYCENTRIC_ATTR_UNIT
) )
{
//cubeGeometry-setVertexAttribData(31,
osg::Geometry::ArrayData(array,osg::Geometry::BIND_PER_VERTEX, GL_FALSE ) );
std::cout setting barycentric attr unit array of size
array-getNumElements() std::endl;
cubeGeometry-setVertexAttribArray(BARYCENTRIC_ATTR_UNIT,
array.get());
Re: [osg-users] Drawing lines using OpenGL ES 2.0
I want to add that this is the fragment shader I used for drawing the wireframe
model
Code:
precision highp float;
varying vec3 vBC;
#extension GL_OES_standard_derivatives : enable
float edgeFactor(){
vec3 d = fwidth(vBC);
vec3 a3 = smoothstep(vec3(0.0), d*1.0, vBC);
return min(min(a3.x, a3.y), a3.z);
}
void main (void)
{
gl_FragColor = vec4(0.0, 0.0, 0.0, (1.0-edgeFactor())*1.0);
}
Special thanks to this blog for the fragment shader and the idea of using
barycentric coordinates!
http://codeflow.org/entries/2012/aug/02/easy-wireframe-display-with-barycentric-coordinates/
--
Read this topic online here:
http://forum.openscenegraph.org/viewtopic.php?p=57117#57117
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Drawing lines using OpenGL ES 2.0
Hi, for learning basic shader programming you do not have to constrain yourself to opengl es 2.0. It is sufficient to do the same basic stuff with OGL 3.0 in order at least to understand the difference between assigning a coordinate value and a color value as the final fragment value. I wanted to help you with that. This was my point. For your app you have to work wherever you need to work in, of course, there you are right. But I am glad you have been able to solve your problem on your own. best, -deniz -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=57118#57118 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] [linux] OSG + X11 and question about osgViewer
« Hi people of OSG mailing list I'm Nicoo, and I come in peace! » well, I try to write a minimal application using X11 and OSG, I would like to know first if the library osgViewer is something written only to help newcomer. I borrowed a book where all examples I saw use osgViewer. I'm interested to have a full control of my camera (position, gaze...) like I do in Opengl. Same for inputs, I'm using X11 key/mouse event. So I'm looking for a tutorial who starts from scratch, using only OSG and X11. I didn't found any tutorial so far. Moreover, I'm bit confused, when I go there : http://trac.openscenegraph.org/projects/osg//wiki/Support/Tutorials and see many tutorials with some note like : Code needs conversion to osgViewer I don't know if it's not wothless to take time to study these tutorials... So I try to write my own application from scratch using X11 and osg. I uploaded a tarball : http://ge.tt/4g9ZzLx/v/0?c so there is the commands to do : $ tar -xvf OSGX11.tar $ cd FlammingCessna $ cmake . $ make $ ./FlammingCessna then you'll see : scrot.png (in the tarball too) as you can see, there is some black parts, I don't know why... (p.s. I don't think they are some burnt triangles... cessnafire... like my invisible roomate says ) -nicoo p.s. : there is a reason why http://trac.openscenegraph.org is so slow ? ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] blending on multiple targets
Hi, I ran into something weird, or something that I don't know how it works exactly. What I want to do when rendering to multiple targets is that I selectively write to certain color buffers in my shader, but leave others alone. for example Code: gl_FragData[3] = vec4(0,1,0,1); without setting the fragment data for the first 3 buffers... This doesn't seem to go well. for example, if I don't explicity set a value in the color buffer 4, it seems to copy the color value from the first color buffer for some reason instead of leaving it alone. So I though: ok I HAVE to explicitly set all a value on all used color buffers, so then if I don't want to touch one of the buffers, I just use blending and I write a value with an alpha of 0, so it doesn't effect the buffer. This doesn't work as expected. It seems that the blending only looks at the color buffer 0 ? if I write a some color-value with an alpha of 0 to the color buffer 0, it doesn't seem to matter what I write to the other buffers, it doesn't write anything. So not sure if you can follow what I'm explaining, but bottom line is: I would like to selectively write to certain color buffers in my shaders, and leave the other alone. Any ideas on how to do that properly? Or am I trying something impossible and do I need another solution? Thank you! Cheers, Bram -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=57121#57121 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] blending on multiple targets
Hi Bram, There is nothing weird about what you are seeing given what you're doing. Blending with MRT ist always applied to all bound render targets of the framebuffer object. If you want to blend only a single buffer, then do a separate pass, where you blend it. In case you want to apply different blend functions to different FBO attachments you cat take a look at: http://www.opengl.org/registry/specs/EXT/draw_buffers2.txt This extension would actually allow to blend only a single attachment. I've asked for support on the mailing list how to use it/integrate into OSG. Unfortunately without any response. But it is undefined behaviour not writing all attached buffers, as you do in your description. So If there is something like gl_FragData[3] = vec4(0,1,0,1); without any gl_FragData[0] .. gl_FragData[2] then you shader is invalid (yet syntactically correct) cheers Sebastian Hi, I ran into something weird, or something that I don't know how it works exactly. What I want to do when rendering to multiple targets is that I selectively write to certain color buffers in my shader, but leave others alone. for example Code: gl_FragData[3] = vec4(0,1,0,1); without setting the fragment data for the first 3 buffers... This doesn't seem to go well. for example, if I don't explicity set a value in the color buffer 4, it seems to copy the color value from the first color buffer for some reason instead of leaving it alone. So I though: ok I HAVE to explicitly set all a value on all used color buffers, so then if I don't want to touch one of the buffers, I just use blending and I write a value with an alpha of 0, so it doesn't effect the buffer. This doesn't work as expected. It seems that the blending only looks at the color buffer 0 ? if I write a some color-value with an alpha of 0 to the color buffer 0, it doesn't seem to matter what I write to the other buffers, it doesn't write anything. So not sure if you can follow what I'm explaining, but bottom line is: I would like to selectively write to certain color buffers in my shaders, and leave the other alone. Any ideas on how to do that properly? Or am I trying something impossible and do I need another solution? Thank you! Cheers, Bram -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=57121#57121 ___ 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
