I’ve been totally brick walled attempting to apply transparency to my characters outfit with UDIMs, however I keep getting proposed the same error message each time I make an attempt to get it to work. Is there an alternative method to getting this transparency to work without having to assign separate texture sets to each of my UDIM tiles? If not, do the UE4 devs plan on fixing this issue in the foreseeable future? Thank you in advance for providing feedback. (FYI, This issue persists in both UE5 and UE4.27)
Use a Masked material and save the alpha mask as linear data into an R G or B channel
Wish there was a way to do this aswell, now I’m the one hitting my head against the wall trying to get something like this to work. The artist on my team insists in using UDIMs, I don’t know what to do T.T I can get transparency to work with the regular opacity pin, but then I get those old problems with depht being completely broken with stuff like eyes and hair sticking out out of the characters head…
The way I managed to make it work was:
In Blender I created two UV Maps: one called “UVMap” and the other called “Texture Mapping” for my mesh.
The UVMap was used to unwrap the mesh into 30 UDIM’s. I baked the Diffuse, Roughness and Normal maps leaving “UVMap” highlighted in properties.
Then, I switched to the “Texture Baking” map, and created a 4096x4096 single image. I baked the Opacity information leaving “Texture Baking” highlighted in the properties.
Then I imported the UDIM’s into UE5 and left the “Virtual Texture Streaming” box ticked in the image properties.
Then I imported the Opacity image into UE5 and left the “Virtual Texture Streaming” box UNTICKED.
Inside the Unreal shader editor, I switched the Material to “Masked” to have the “Opacity Mask” input available and connected the Opacity image into it. Then, I prompted a “TextureCoordinate” node that I connected to the UV input of the Opacity mask and switched the channel “1” (while all other UV channels for the UDIM’s were left at “0”)