Houdini 21.0 Nodes Copernicus nodes

Match UDIM Copernicus node

Reframes pixels of a layer to match a particular UDIM tile.

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Since 21.0

UDIMs provide a way of extending texture space beyond the usual unit square. This is done by breaking up the space into tiles and treating each tile as its own texture. A simple method is used to enumerate the tiles, and the image below shows how they are laid out relative to one another.

This node reframes the pixels of a layer to match a particular UDIM tile. The node virtually moves the image from the starting tile to the destination tile, in the camera’s space. This node is useful for rasterization, where it can help you isolate a specific tile.

How to

For example, use the following steps to bake down attributes on a model to UDIM textures, one tile at a time.

  1. Use the Layer COP to create a new canvas for rasterization.

  2. Wire the Layer COP’s output into the Match UDIM COP.

  3. Bring your geometry into the Copernicus context. You can do this with the SOP Import COP.

  4. Wire this geometry into the Rasterize Setup COP.

  5. In the Rasterize Setup COP, set Space to UVs. You can now rasterize the target attribute.

  6. Create a Rasterize Geometry COP.

  7. Wire your canvas (the Match UDIM COP’s output) into the rasterizer’s camera_ref input and your flattened model (the Rasterize Setup COP’s output) into the geometry input.

  8. The Rasterize Geometry COP’s output is a single tile that contains the desired rasterized attribute. To change the current tile, use the Match UDIM COP’s UDIM parameter or set the appropriate context option.

Parameters

UDIM

The tile at which to relocate the input image (assuming its starting position corresponds to tile 1001).

Invert Transformation

Inverts the transformation. This relocates the input image from the UDIM value to tile 1001.

Method

The method used to move the image.

Move Camera

Reposition the camera so it’s looking at the desired tile.

Adjust Data Window

Don’t move the camera, but instead change the layer’s data window to move its pixels outside of the display window.

Inputs

source

The input image to reframe.

Outputs

result

The reframed image that has the same pixel data as source.

See also

Copernicus nodes