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Does anyone have any idea that when I link something like a noise texture to the offset socket of Set Position node, and look at the offset value through attribute, it does not equal the position value of the corresponding point? When I unlink it and input a constant value instead, it works. As shown in the snapshots. enter image description here

enter image description here

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The combine XYZ output is evaluated using the geometry given to the node it plugs into. So, the Set Position node evaluates the value of the noise texture using the geometry from the group input. However, the Group Output node evaluates it using the geometry it receives from Set Position, which has already been shifted on the Z axis.

This means the noise texture vector input is the original vertex positions when attached to the Set Position, but is the shifted vertex positions when attached to the group output, and so the values are different. To get the value you're looking for, you can capture the attribute before it goes into the group output. setup

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  • $\begingroup$ This specific case is also mentioned in the docs $\endgroup$ Dec 17, 2021 at 0:15
  • $\begingroup$ @MarkusvonBroady : so you are the one who reads the docs! Come on man, that’s not fair! 😎 $\endgroup$
    – Chris
    Dec 17, 2021 at 2:42
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    $\begingroup$ @Chris not that I understand it... I'm considering improving the docs eventually, not sure where to start, though... $\endgroup$ Dec 17, 2021 at 9:33
  • $\begingroup$ For me personally example help me best understanding something. So I am always happy if the docs as in bpy api sometimes have example code. I love animation nodes docs for a lot of node setup examples. We should have that for geonodes too. But we have also lots of great tutorials on yt e.g. Erindale… $\endgroup$
    – Chris
    Dec 17, 2021 at 9:47
  • $\begingroup$ And I have to admit that I don’t understand 30% of the docs….🙈 $\endgroup$
    – Chris
    Dec 17, 2021 at 9:48

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