Hi,
Is there a way in GEM to take a snapshot of a rendered scene (such as with pix_snap) and save the z-buffer information, for example saving it as an extra channel? (e.g. have the z value saved as the alpha channel)?
I'm interested in getting an image of the scene as it would appear if it was captured by a depth sensor like a Kinect...
Thanks m.
On Fri, 10 Jun 2011, Matteo Sisti Sette wrote:
Is there a way in GEM to take a snapshot of a rendered scene (such as with pix_snap) and save the z-buffer information, for example saving it as an extra channel? (e.g. have the z value saved as the alpha channel)? I'm interested in getting an image of the scene as it would appear if it was captured by a depth sensor like a Kinect...
How many bits do you expect the z-buffer to be, and how can that possibly fit in any GEM pix structure ?
AFAIK, only GridFlow, PDP and iemmatrix are equipped to handle that data.
| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC
It is possible to use shader to define the z-buffer. gl_ModelViewMatrix * gl_Vertex gives the eye coordinate position of each vertex (it is what we need here to define the depth of each vertex). See example attached. You can change this example to apply the depth to alpha channel. ++
Jack
Le mercredi 15 juin 2011 à 17:09 -0400, Mathieu Bouchard a écrit :
On Fri, 10 Jun 2011, Matteo Sisti Sette wrote:
Is there a way in GEM to take a snapshot of a rendered scene (such as with pix_snap) and save the z-buffer information, for example saving it as an extra channel? (e.g. have the z value saved as the alpha channel)? I'm interested in getting an image of the scene as it would appear if it was captured by a depth sensor like a Kinect...
How many bits do you expect the z-buffer to be, and how can that possibly fit in any GEM pix structure ?
AFAIK, only GridFlow, PDP and iemmatrix are equipped to handle that data.
| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC _______________________________________________ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Le jeudi 16 juin 2011 à 14:21 +0200, Jack a écrit :
It is possible to use shader to define the z-buffer.
What i mean is not z-buffer but depth of a vertex. ++
Jack
gl_ModelViewMatrix * gl_Vertex gives the eye coordinate position of each vertex (it is what we need here to define the depth of each vertex). See example attached. You can change this example to apply the depth to alpha channel. ++
Jack
Le mercredi 15 juin 2011 à 17:09 -0400, Mathieu Bouchard a écrit :
On Fri, 10 Jun 2011, Matteo Sisti Sette wrote:
Is there a way in GEM to take a snapshot of a rendered scene (such as with pix_snap) and save the z-buffer information, for example saving it as an extra channel? (e.g. have the z value saved as the alpha channel)? I'm interested in getting an image of the scene as it would appear if it was captured by a depth sensor like a Kinect...
How many bits do you expect the z-buffer to be, and how can that possibly fit in any GEM pix structure ?
AFAIK, only GridFlow, PDP and iemmatrix are equipped to handle that data.
| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC _______________________________________________ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
2011/6/16 Jack jack@rybn.org:
Le jeudi 16 juin 2011 à 14:21 +0200, Jack a écrit :
It is possible to use shader to define the z-buffer.
What i mean is not z-buffer but depth of a vertex.
Yeah that's exactly what I was looking for. I thought that depth was what is saved in the z-buffer. My understanding of OpenGL is quite poor...
Thank you very much m.
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Jack -
Mathieu Bouchard -
Matteo Sisti Sette -
matteo sisti sette