Forums Solaris and Karma Motion vector AOV in Karma

Motion vector AOV in Karma

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haymaker
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Is it possible to do in karma. Does anyone still use it?
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TangheStudent
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This seems to do the thing.
Edited by TangheStudent - March 25, 2022 19:38:41

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houdini_Rh5eGENm98.png (10.5 KB)

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jerry7
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TangheStudent
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This seems to do the thing.

Hi,
I tested ,but it has not effect because there is no velocities primvar if animating by transform lop.
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TangheStudent
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what you need to do then is add the v atribute with a trail sop and rename it to velocities.
It could be that you need to promote the attribute to a primitive aswel wich might paint ver primitive instead of point.
But i haven`t tested out if it works with points.
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No_ha
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Just to note this. As far as I can see, the velocities described in this thread are only taking into account the velocity on the geometry not the geometry relative to the camera.
But I also can’t give any explanation on how to create a proper motion vector AOV like in mantra.
Edited by No_ha - May 29, 2022 02:42:35
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arx_anima
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the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity
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jerry7
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arx_anima
the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity

Hi,
I tried ray:motionvector and ray:velocity, but can't get the result.
Could you give any tip?

Thanks!

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mvector.png (169.4 KB)

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mark
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I think you'll find that this will have a much improved workflow in the next major version of Houdini.
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agastyafx
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What's the difference between motion vector and velocity. Is it with respect to camera? I'm getting data rendered in motionvector but not in velocity
arx_anima
the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity
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jsmack
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agastyafx
What's the difference between motion vector and velocity. Is it with respect to camera? I'm getting data rendered in motionvector but not in velocity
arx_anima
the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity

motionvector is a screenspace vector, useful for post processing applications of motion blur. I'm not sure what ray:velocity is, but it's probably in world space.
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ysysimon
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jerry7
arx_anima
the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity

Hi,
I tried ray:motionvector and ray:velocity, but can't get the result.
Could you give any tip?

Thanks!





It's seems to be a Houdini19.5 things.

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motion_V.jpg (32.7 KB)

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APESTARSTREAK
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it doesnt work in xpu
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nicolaas.tanghe
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you can do a pass with cpu where you don't render anything except the aov.
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pranesh arry
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arx_anima
the karma node or the karma standart rendervars node has motion vectors and velocity aov as default to check.
We used them already in production and they work fine, they do not use primvars but a ray level check
ray:motionvector
ray:velocity

Hey there,
I tried checking both the motionvector and velocity in the karma render node, however I still get a blank output. Am I missing something?

Thanks!

Attachments:
rendervars.png (34.6 KB)
noop.png (49.6 KB)

Pranesh Arry
3D Generalist at North Studio
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0x384c0
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For motion vector to appear in renders do not forget to setup "Motion Blur" in Karma Render Properties [www.sidefx.com] and cache [www.sidefx.com] your animation.
Edited by 0x384c0 - June 21, 2023 08:46:15
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