Creating a UV Map from Within Nuke


#1

Hello i am trying to be able to project an image onto a scene downward and from the ‘Y’ axis.

I don’t want to bring in any 3d geo into nuke or use any external plugins.

And I was thinking if I can use the Point Position Pass in a 3d scene, and a projection camera, and somehow output a UV pass out of it, I can do it that way?

Please let me know if anyone has any ideas or if I need to clarify things more.


#2

Just apply a UV map as a texture to your geo. You can make one really easily with an expression node.

set cut_paste_input [stack 0]
Expression {
expr0 (x+0.5)/(width)
expr1 (y+0.5)/(height)
name Expression1
selected true
}


#3

Did you ever figure this out? I’m stuck on this one as well. Thanks!


#4

sorry that would require bringing 3d geo into nuke which isn’t an option.

Basically how do I convert a pworld pass into a uv pass?


#5

For whoever still looks for a solution, you can use the position map as UVs in a STMap node. The issue is the position map values quickly go above 1. You need to apply a very low grade>multiply node to bring those values down. It’s still not going to tile though. A solution to make this tile is to loop the colors back to 0 as soon as they reach 1, you can use a ColorLookup, add points to the curve on the left and right to create a jigsaw looking curve that goes back to 0 as soon as it reaches 1, then loop… Do that for as many tiling as you need…