Problem with 3D noise / position [xpu]

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I'm generating a noise pass from XPU and it's oddly not consistent across my geometry. I'm just using a mtlx position using world space and it works and looks fine if the noise is low frequency but when it's high you can clearly see the different objects . I'm using the P pass in COPs instead for the moment, which will probably do what I'm after but I'd like to understand why it isn't working in shader.

Attached low and high frequency noise renders .
Edited by j00ey - July 30, 2024 04:06:16

Attachments:
noise_highFreq.jpg (513.5 KB)
noise_lowFreq.jpg (389.4 KB)

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What's the scale of that object? I've had strange issues on very large things that weren't apparent on more normal sizes.
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Ah that's interesting - it's quite large, that section in camera above is approx 110 metres left to right...

There is some odd stuff going on at much more normal scales too though - this highlighted area is a planar area approx 1m high and is striated. I've tried fiddling with dicing settings and stuff like that and it doesn't seem to make any difference.

My position pass is fine and if I pipe the output of the mtlx_position that's driving the noise into an AOV it looks fine.

Attachments:
noise_highFreq2.jpg (1000.9 KB)

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