Export UDIM layout?

Question

I tried to export UDIM layout grid of 3, but only the first 1001 gets exported. Is there a way to export all parts of the grid?

Answer 1

The Blender UDIM workflow is pretty awful right now IMO, and the documentation is severely lacking. Here's the procedure to get what you want.

1) Create your object and UV unwrap it.

2) In the UV Editor, open the N menu, click View and expand UDIM Grid. Input the number of columns and rows you want for your UDIM grid. Move your unwrapped UVs to whatever grid you want.

3) Click the + New button to create a new texture image. Name it whatever you want, size it however you want, fill it however you want, but make sure to check Tiled under Generated Type.

4) Go to the Image section of the N menu and expand the UDIM Tiles section. Tile 1001 should already be in the list. Click the + button to add tile 1002. Fill it however you want. Make it whatever size you want, etc.

N.B. You can increase the Count number here to add as many tiles as you want with a single click. They will all be the same size and filled with whatever generated image or flat fill you pick in this dialog.

5) Once this is done, you should see a complete set of UV tiles in your UDIM set.

6) Click Image > Save As.. in the UV Editor menu. Choose a folder to save your UV texture files. The name of the file should be auto set to .1001.png

Click Save As Image.

7) Check that folder and you should see that the 1001, 1002 and 1003 image files were automatically created.

8) Edit your textures in whatever way you want. Open the Shader Editor. Create a Material and create the standard Texture Coordinate > Mapping > Image Texture > Shader tree. Make sure that UV is the selected Texture Coordinate output.

9) Select the 1001 image file as the selected image in the Image Texture node. Make sure Tiled is selected.

The other UVs will automagically attach themselves to the other parts of your object.

Answer 2

Answer 1 has nothing to do with exporting UDIM UV layouts from UDIM tiles, it does have do with texturing objects with UDIM tiles. All the poster is doing in the first step is create a full page texture for each tile from Blender generated textures, it doesn't give the island outlines of the object itself.

To date (28 June, 2020) there still isn't a way to actually export UV layouts other than tile 1001. There is an open bug report on this and it has been handed to the development team, so when there might be a fix, who knows.

I've tried to set up nodes to at least bake a coloured texture for each tile from a UV Bake, but even that doesn't seem possible.

My current work around, is to export the model itself and use a texturing/paint program (like Substance Painter) that uses UDIMs to paint it. The output from the paint program creates the tiled textures.

Following the texturing process in Answer 1 will texture the model using the tile textures in Blender, but for the actual islands themselves, I don't think it's possible yet.

Answer 3

Here is a workaround, it's a bit tedious but it works:

• Select tile 1001 and export UV Layout as usual
• Hide selected faces on tile 1001
• Move the next tile into 1001 using G+X/Y+1/-1
• Export and repeat

Note that this method is used by me to map images/alpha masks in Photoshop that I export later to Substance Painter.

Answer 4

I've done a little addon to export udim tiles between a range
Here's the link to it, let me know if there's bugs or things to improve

https://cscholl.fr/blender-addons/

Answer 5

I figured out how to go from DAZ to Blender to Substance Painter.

Key was getting the character into blender as a single object instead of multiples. With that set I only had one option in the Material window. Other attempts yield bad results where I could only generate one texture. Using blender 2.90 and substance painter 6.2.0. I did have to use the UV selection mode in order to move everything to new tiles, possible with some patience.

Again, key is getting Blender to import in and export out as a single object, shown in first pic, one slot, with udims.