Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-03-01 Thread Sergey Polischuk
Hi, Martin
iirc i've used full gl style as i cant make it work with just osg default 
drawimplementation + state management (like program and modes) atm (i mean i 
tried for a week or two and it just wasnt working, and this stuff really hard 
to debug when it draws crap or crashes in driver, i dont remember details as it 
was like two years ago or so) You can try, may be you got some luck. I think it 
is possible to do this with osg program and buffer objects management, then 
things get a lot simplier as you dont need to initialize all stuff yourself.
and this was just first more or less working sample (still no multiple context 
safe, and may be have some other bugs), things changed quite a bit since then

also with gl 4.2 you can drop queries, as you have drawTransformFeedback, but 
then you cant use osg draw implementation

As for guides for embedding gl into osg... i dont saw any. You can dig into 
osg::Geometry\StateAttributes\osg::State sources to see how it done in osg 
itself. From my experience i can say that if you make gl state changes via gl 
functions yourself you should let osg know about them(check osg::State 
reference). If something not working try to revert all state changes you've 
done after your drawing (unbind buffers\arrays, revert fbo bindings, active 
texture units, vertex attrib arrays, programs, etc...)

01.03.2012, 20:46, "Martin Groer" :
> Hello Sergey,
>
> thank you, it is good to know. I am a little bit frustrated. I read about 
> OpenGL 4.2 and transform feedback and was so happy about this. That sounds so 
> easy to use. By now it is hard to implement a simple first example. :-(
>
> I found this thread: 
> http://www.mail-archive.com/osg-users@lists.openscenegraph.org/msg46962.html
>
> You made this example, right? So far, I don't understand all the stuff. Is 
> this all necessary for transform feedback?
>
> I only need the follow functions, don't I?
>
> 1. glTransformFeedbackVaryings
> 2. glBindBufferBase
> 3. glBeginTransformFeedback
> 4. glEndTransformFeedback
>
> For example, is a loadShaderFromFile function necessary? Is this only 
> necessary, because the glTransformFeedbackVaryings have to be between the 
> compiling and linking of the shader?
>
> I think my first problem is I don't have any experience with OpenGL code 
> embedded into osg code. Are there any examples, tutorials or articles about 
> this?
>
> I will keep on trying!
>
> Cheers,
> Martin
>
>  Original-Nachricht ----
>
>>  Datum: Thu, 01 Mar 2012 19:34:42 +0400
>>  Von: Sergey Polischuk 
>>  An: OpenSceneGraph Users 
>>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
>>  Generally you should use interfaces provided by osg to get to opengl
>>  functions, as they can have different pointers in different graphics 
>> contexts.
>>
>>  so it goes like
>>
>>  typedef void (APIENTRY * TransformFeedbackVaryings)(GLuint, GLsizei, const
>>  GLchar **, GLenum);
>>  TransformFeedbackVaryings _glTransformFeedbackVaryingsPtr;
>>  if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr,
>>  "glTransformFeedbackVaryings" ))
>>   if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr,
>>  "glTransformFeedbackVaryingsEXT" ))
>>    //not supported :(
>>  // so now you can use this pointer in this gc
>>
>>  also if you need some opengl functions, first check osg::GL2Extensions, it
>>  may be already wrapped and initialized there.
>>  All of this should be called with active graphics context
>>
>>  Cheers
>>
>>  29.02.2012, 18:22, "Martin Groer" :
>>>  Hello,
>>>
>>>  I tried this in my camera draw callback:
>>>
>>>  virtual void operator()(const osg::Camera& camera) const
>>>  {
>>>    // GL-Context-ID
>>>    GLuint gcID = _gc->getState()->getContextID();
>>>
>>>    // GL-Program-Handle
>>>    osg::Program::PerContextProgram* pcp = _program->getPCP(gcID);
>>>    GLuint prID=pcp->getHandle();
>>>
>>>    const char* varyings[1] = { "vPosition" };
>>>    glTransformFeedbackVaryings(prID, 1, varyings, GL_SEPARATE_ATTRIBS);
>>>  }
>>>
>>>  But when I want to compile this, I get the error
>>  "glTransformFeedbackVaryings isn't defined". I searched in my includes and 
>> it is in the glext.h
>>  and glew.h defined. What is wrong?
>>>  Cheers,
>>>  Martin
>>>
>>>   Original-Nachricht 
>>>>   Datum: Tue, 28 Feb 2012 10:45:16 -0700
>>>>   Von: Paul Martz 
>&

Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-03-01 Thread Martin Großer
Hello Sergey,

thank you, it is good to know. I am a little bit frustrated. I read about 
OpenGL 4.2 and transform feedback and was so happy about this. That sounds so 
easy to use. By now it is hard to implement a simple first example. :-(

I found this thread: 
http://www.mail-archive.com/osg-users@lists.openscenegraph.org/msg46962.html

You made this example, right? So far, I don't understand all the stuff. Is this 
all necessary for transform feedback?

I only need the follow functions, don't I?

1. glTransformFeedbackVaryings
2. glBindBufferBase
3. glBeginTransformFeedback
4. glEndTransformFeedback

For example, is a loadShaderFromFile function necessary? Is this only 
necessary, because the glTransformFeedbackVaryings have to be between the 
compiling and linking of the shader?

I think my first problem is I don't have any experience with OpenGL code 
embedded into osg code. Are there any examples, tutorials or articles about 
this?

I will keep on trying!

Cheers,
Martin


 Original-Nachricht 
> Datum: Thu, 01 Mar 2012 19:34:42 +0400
> Von: Sergey Polischuk 
> An: OpenSceneGraph Users 
> Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

> Generally you should use interfaces provided by osg to get to opengl
> functions, as they can have different pointers in different graphics contexts.
> 
> so it goes like
> 
> typedef void (APIENTRY * TransformFeedbackVaryings)(GLuint, GLsizei, const
> GLchar **, GLenum);
> TransformFeedbackVaryings _glTransformFeedbackVaryingsPtr;
> if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr, 
> "glTransformFeedbackVaryings" ))
>  if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr, 
> "glTransformFeedbackVaryingsEXT" ))
>   //not supported :(
> // so now you can use this pointer in this gc
> 
> 
> also if you need some opengl functions, first check osg::GL2Extensions, it
> may be already wrapped and initialized there.
> All of this should be called with active graphics context
> 
> 
> Cheers
> 
> 
> 29.02.2012, 18:22, "Martin Groer" :
> > Hello,
> >
> > I tried this in my camera draw callback:
> >
> > virtual void operator()(const osg::Camera& camera) const
> > {
> >   // GL-Context-ID
> >   GLuint gcID = _gc->getState()->getContextID();
> >
> >   // GL-Program-Handle
> >   osg::Program::PerContextProgram* pcp = _program->getPCP(gcID);
> >   GLuint prID=pcp->getHandle();
> >
> >   const char* varyings[1] = { "vPosition" };
> >   glTransformFeedbackVaryings(prID, 1, varyings, GL_SEPARATE_ATTRIBS);
> > }
> >
> > But when I want to compile this, I get the error
> "glTransformFeedbackVaryings isn't defined". I searched in my includes and it 
> is in the glext.h
> and glew.h defined. What is wrong?
> >
> > Cheers,
> > Martin
> >
> >  Original-Nachricht 
> >
> >>  Datum: Tue, 28 Feb 2012 10:45:16 -0700
> >>  Von: Paul Martz 
> >>  An: OpenSceneGraph Users 
> >>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
> >>  On 2/28/2012 9:10 AM, "Martin Großer" wrote:
> >>>  Hello Paul,
> >>>
> >>>  In OpenGL I have to define the varying variables for the transform
> >>  feedback between the compiling and linking of the shader program.
> >>>  glTransformFeedbackVaryings(programHandle, 1, varyings,
> >>  GL_SEPARATE_ATTRIBS);
> >>>  How can I do this in OSG?
> >>  The same way. You can issue an OpenGL call any time you have a
> current
> >>  context
> >>  (Camera pre draw callback, Drawable draw callback, etc).
> >>
> >>  A quick glance at the Program header file reveals that you can get
> the
> >>  program
> >>  ID with a call to:
> >> osg::Program::getPCP(contextID)->getHandle();
> >>>  Additinally I use osg 2.8.4 from the Fedora repository.
> >>>
> >>>  Cheers,
> >>>  Martin
> >>>
> >>>   Original-Nachricht 
> >>>>  Datum: Mon, 27 Feb 2012 09:51:15 -0700
> >>>>  Von: Paul Martz
> >>>>  An: OpenSceneGraph Users
> >>>>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
> >>>>  Yes, it's possible, but there are no examples that I know of. You
> might
> >>>>  try
> >>>>  binding a buffer object in a Camera pre-draw callback, for an
> example
> >>  of
> >>>>  one
> >>>>  strategy.
> >>>>   -Pa

Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-03-01 Thread Sergey Polischuk
Generally you should use interfaces provided by osg to get to opengl functions, 
as they can have different pointers in different graphics contexts.

so it goes like

typedef void (APIENTRY * TransformFeedbackVaryings)(GLuint, GLsizei, const 
GLchar **, GLenum);
TransformFeedbackVaryings _glTransformFeedbackVaryingsPtr;
if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr,  
"glTransformFeedbackVaryings" ))
 if (!osg::setGLExtensionFuncPtr(_glTransformFeedbackVaryingsPtr,  
"glTransformFeedbackVaryingsEXT" ))
  //not supported :(
// so now you can use this pointer in this gc


also if you need some opengl functions, first check osg::GL2Extensions, it may 
be already wrapped and initialized there.
All of this should be called with active graphics context


Cheers


29.02.2012, 18:22, "Martin Groer" :
> Hello,
>
> I tried this in my camera draw callback:
>
> virtual void operator()(const osg::Camera& camera) const
> {
>   // GL-Context-ID
>   GLuint gcID = _gc->getState()->getContextID();
>
>   // GL-Program-Handle
>   osg::Program::PerContextProgram* pcp = _program->getPCP(gcID);
>   GLuint prID=pcp->getHandle();
>
>   const char* varyings[1] = { "vPosition" };
>   glTransformFeedbackVaryings(prID, 1, varyings, GL_SEPARATE_ATTRIBS);
> }
>
> But when I want to compile this, I get the error "glTransformFeedbackVaryings 
> isn't defined". I searched in my includes and it is in the glext.h and glew.h 
> defined. What is wrong?
>
> Cheers,
> Martin
>
> ---- Original-Nachricht 
>
>>  Datum: Tue, 28 Feb 2012 10:45:16 -0700
>>  Von: Paul Martz 
>>  An: OpenSceneGraph Users 
>>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
>>  On 2/28/2012 9:10 AM, "Martin Großer" wrote:
>>>  Hello Paul,
>>>
>>>  In OpenGL I have to define the varying variables for the transform
>>  feedback between the compiling and linking of the shader program.
>>>  glTransformFeedbackVaryings(programHandle, 1, varyings,
>>  GL_SEPARATE_ATTRIBS);
>>>  How can I do this in OSG?
>>  The same way. You can issue an OpenGL call any time you have a current
>>  context
>>  (Camera pre draw callback, Drawable draw callback, etc).
>>
>>  A quick glance at the Program header file reveals that you can get the
>>  program
>>  ID with a call to:
>> osg::Program::getPCP(contextID)->getHandle();
>>>  Additinally I use osg 2.8.4 from the Fedora repository.
>>>
>>>  Cheers,
>>>  Martin
>>>
>>>   Original-Nachricht 
>>>>  Datum: Mon, 27 Feb 2012 09:51:15 -0700
>>>>  Von: Paul Martz
>>>>  An: OpenSceneGraph Users
>>>>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
>>>>  Yes, it's possible, but there are no examples that I know of. You might
>>>>  try
>>>>  binding a buffer object in a Camera pre-draw callback, for an example
>>  of
>>>>  one
>>>>  strategy.
>>>>   -Paul
>>>>
>>>>  On 2/27/2012 8:21 AM, "Martin Großer" wrote:
>>>>>  Hello,
>>>>>
>>>>>  Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in
>>  osg?
>>>>  I would like write back my vertex position data into a new Vertex
>>  Buffer
>>>>  Object. Is there any example about this?
>>>>>  Cheers
>>>>>
>>>>>  Martin
>>>>  ___
>>>>  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
> --
> NEU: FreePhone 3-fach-Flat mit kostenlosem Smartphone!
> Jetzt informieren: http://mobile.1und1.de/?ac=OM.PW.PW003K20328T7073a
> ___
> 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] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-29 Thread Jason Daly

On 02/29/2012 09:22 AM, "Martin Großer" wrote:

Hello,

I tried this in my camera draw callback:

virtual void operator()(const osg::Camera&  camera) const
{
   // GL-Context-ID
   GLuint gcID = _gc->getState()->getContextID();

   // GL-Program-Handle
   osg::Program::PerContextProgram* pcp = _program->getPCP(gcID);
   GLuint prID=pcp->getHandle();

   const char* varyings[1] = { "vPosition" };
   glTransformFeedbackVaryings(prID, 1, varyings, GL_SEPARATE_ATTRIBS);
}

But when I want to compile this, I get the error "glTransformFeedbackVaryings isn't 
defined". I searched in my includes and it is in the glext.h and glew.h defined. 
What is wrong?


On Linux, you might need to #define GL_GLEXT_PROTOTYPES

On Windows, you have to look up the function with wglGetProcAddress

In both cases, it's generally a good idea to test for the extension 
first (OSG normally does for you in osg::GLExtensions).


--"J"

___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org


Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-29 Thread Martin Großer
Hello,

I tried this in my camera draw callback:

virtual void operator()(const osg::Camera& camera) const
{
  // GL-Context-ID
  GLuint gcID = _gc->getState()->getContextID();

  // GL-Program-Handle
  osg::Program::PerContextProgram* pcp = _program->getPCP(gcID);
  GLuint prID=pcp->getHandle();

  const char* varyings[1] = { "vPosition" };
  glTransformFeedbackVaryings(prID, 1, varyings, GL_SEPARATE_ATTRIBS);
}

But when I want to compile this, I get the error "glTransformFeedbackVaryings 
isn't defined". I searched in my includes and it is in the glext.h and glew.h 
defined. What is wrong?

Cheers,
Martin

 Original-Nachricht 
> Datum: Tue, 28 Feb 2012 10:45:16 -0700
> Von: Paul Martz 
> An: OpenSceneGraph Users 
> Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

> On 2/28/2012 9:10 AM, "Martin Großer" wrote:
> > Hello Paul,
> >
> > In OpenGL I have to define the varying variables for the transform
> feedback between the compiling and linking of the shader program.
> >
> > glTransformFeedbackVaryings(programHandle, 1, varyings,
> GL_SEPARATE_ATTRIBS);
> >
> > How can I do this in OSG?
> 
> The same way. You can issue an OpenGL call any time you have a current
> context 
> (Camera pre draw callback, Drawable draw callback, etc).
> 
> A quick glance at the Program header file reveals that you can get the
> program 
> ID with a call to:
>osg::Program::getPCP(contextID)->getHandle();
> 
> > Additinally I use osg 2.8.4 from the Fedora repository.
> >
> > Cheers,
> > Martin
> >
> >  Original-Nachricht 
> >> Datum: Mon, 27 Feb 2012 09:51:15 -0700
> >> Von: Paul Martz
> >> An: OpenSceneGraph Users
> >> Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
> >
> >> Yes, it's possible, but there are no examples that I know of. You might
> >> try
> >> binding a buffer object in a Camera pre-draw callback, for an example
> of
> >> one
> >> strategy.
> >>  -Paul
> >>
> >>
> >> On 2/27/2012 8:21 AM, "Martin Großer" wrote:
> >>> Hello,
> >>>
> >>> Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in
> osg?
> >> I would like write back my vertex position data into a new Vertex
> Buffer
> >> Object. Is there any example about this?
> >>>
> >>> Cheers
> >>>
> >>> Martin
> >> ___
> >> 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

-- 
NEU: FreePhone 3-fach-Flat mit kostenlosem Smartphone!  

Jetzt informieren: http://mobile.1und1.de/?ac=OM.PW.PW003K20328T7073a
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org


Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-28 Thread Paul Martz

On 2/28/2012 9:10 AM, "Martin Großer" wrote:

Hello Paul,

In OpenGL I have to define the varying variables for the transform feedback 
between the compiling and linking of the shader program.

glTransformFeedbackVaryings(programHandle, 1, varyings, GL_SEPARATE_ATTRIBS);

How can I do this in OSG?


The same way. You can issue an OpenGL call any time you have a current context 
(Camera pre draw callback, Drawable draw callback, etc).


A quick glance at the Program header file reveals that you can get the program 
ID with a call to:

  osg::Program::getPCP(contextID)->getHandle();


Additinally I use osg 2.8.4 from the Fedora repository.

Cheers,
Martin

 Original-Nachricht 

Datum: Mon, 27 Feb 2012 09:51:15 -0700
Von: Paul Martz
An: OpenSceneGraph Users
Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG



Yes, it's possible, but there are no examples that I know of. You might
try
binding a buffer object in a Camera pre-draw callback, for an example of
one
strategy.
 -Paul


On 2/27/2012 8:21 AM, "Martin Großer" wrote:

Hello,

Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in osg?

I would like write back my vertex position data into a new Vertex Buffer
Object. Is there any example about this?


Cheers

Martin

___
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] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-28 Thread Sergey Polischuk
Hi, Martin

afaik, there is no way, you should use opengl calls to get it working

28.02.2012, 20:10, "Martin Groer" :
> Hello Paul,
>
> In OpenGL I have to define the varying variables for the transform feedback 
> between the compiling and linking of the shader program.
>
> glTransformFeedbackVaryings(programHandle, 1, varyings, GL_SEPARATE_ATTRIBS);
>
> How can I do this in OSG?
>
> Additinally I use osg 2.8.4 from the Fedora repository.
>
> Cheers,
> Martin
>
>  Original-Nachricht 
>
>>  Datum: Mon, 27 Feb 2012 09:51:15 -0700
>>  Von: Paul Martz 
>>  An: OpenSceneGraph Users 
>>  Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG
>>  Yes, it's possible, but there are no examples that I know of. You might
>>  try
>>  binding a buffer object in a Camera pre-draw callback, for an example of
>>  one
>>  strategy.
>>  -Paul
>>
>>  On 2/27/2012 8:21 AM, "Martin Großer" wrote:
>>>  Hello,
>>>
>>>  Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in osg?
>>  I would like write back my vertex position data into a new Vertex Buffer
>>  Object. Is there any example about this?
>>>  Cheers
>>>
>>>  Martin
>>  ___
>>  osg-users mailing list
>>  osg-users@lists.openscenegraph.org
>>  http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
> --
> Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir
> belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de
> ___
> 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] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-28 Thread Martin Großer
Hello Paul,

In OpenGL I have to define the varying variables for the transform feedback 
between the compiling and linking of the shader program.

glTransformFeedbackVaryings(programHandle, 1, varyings, GL_SEPARATE_ATTRIBS);

How can I do this in OSG?

Additinally I use osg 2.8.4 from the Fedora repository.

Cheers,
Martin

 Original-Nachricht 
> Datum: Mon, 27 Feb 2012 09:51:15 -0700
> Von: Paul Martz 
> An: OpenSceneGraph Users 
> Betreff: Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

> Yes, it's possible, but there are no examples that I know of. You might
> try 
> binding a buffer object in a Camera pre-draw callback, for an example of
> one 
> strategy.
> -Paul
> 
> 
> On 2/27/2012 8:21 AM, "Martin Großer" wrote:
> > Hello,
> >
> > Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in osg?
> I would like write back my vertex position data into a new Vertex Buffer
> Object. Is there any example about this?
> >
> > Cheers
> >
> > Martin
> ___
> osg-users mailing list
> osg-users@lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org

-- 
Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir
belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org


Re: [osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-27 Thread Paul Martz
Yes, it's possible, but there are no examples that I know of. You might try 
binding a buffer object in a Camera pre-draw callback, for an example of one 
strategy.

   -Paul


On 2/27/2012 8:21 AM, "Martin Großer" wrote:

Hello,

Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in osg? I would 
like write back my vertex position data into a new Vertex Buffer Object. Is 
there any example about this?

Cheers

Martin

___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org


[osg-users] GL_TRANSFORM_FEEDBACK_BUFFER_NV in OSG

2012-02-27 Thread Martin Großer
Hello,

Is it possible to use GL_TRANSFORM_FEEDBACK_BUFFER_NV extension in osg? I would 
like write back my vertex position data into a new Vertex Buffer Object. Is 
there any example about this?

Cheers

Martin
-- 
NEU: FreePhone 3-fach-Flat mit kostenlosem Smartphone!  

Jetzt informieren: http://mobile.1und1.de/?ac=OM.PW.PW003K20328T7073a
___
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org