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F00f C7c8 avatar image
F00f C7c8 asked ·

Offsetting the UV coordinates beyond 0, 1

Greetings to all.

Is it possible to somehow offset the UV coordinates in a shading network beyond the usual [0, 1] space? I am trying to do this to force the image node to return the texture value of a specific UDIM tile.

I know that this can probably be done with the uv_coords input on the image node, but the manual states that using this input can have a detrimental effect on rendering performance. It looks like uv_transform could probably do something like this, but it seems to insist on wrapping the UV coordinates to the [0, 1] space in some manner.

Is something like this possible without writing my own shader to do so?

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Peter Horvath avatar image
Peter Horvath answered ·

The image shader uses the original UVs from the mesh to locate the UDIM tile, that's why the uv_transform has no effect here.

I think your best option is to override the uv_coords, or use a custom UV set. Don't think it will cause a noticeable overhead to be honest.

Here's a simple example of a network which overrides UV coords of an image shader with a modified U coordinate:


udim-uv-coords.png (22.9 KiB)
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