Why we need to do this, instead of another approach
So a bunch of node groups for various projects we’ve seen around have back and forth redrawing the same image with various vector changes, and it’s a pain to mess with multiple copies of the same nested node group as you have to basically reimport the whole thing over and over again to correctly duplicate it.
Plus with using procedural textures you end up regenerating the texture for every deformation step. For a setup like parallax this can get pretty inefficient and laggy in the view port.
So our solution to both of these (that we can’t seem to figure out how to implement) is to pass the original image along from outside the node group to a custom pynode that reapplies texture mapping/ standing in as a proxy, allowing the entire group to be duplicated easily, and saving our poor computer from constant regenerating of various noise textures and such.
Sooo… we don’t know what we’re doing to be honest after tons of digging into this we’re no closer than when we started, except now we have an idea of sorta maybe what we need to do, so we made an account to ask since information on Pynodes is… lacking.
So we need to run existing mapped color data through the texturemapping function (the internal one shader texture nodes use, not the node that maps vectors) like it was drawing and image texture.
We thought about just forcing an internal node tree imagetexture node to read texture data from import, but we don’t know how to do that or if it’ll work. We don’t want to learn to write a node to do this in c and then figure out how to work that with a pynode to connect it… becuase it’d be a pain and we don’t know how too.
We saw someone trying something like this with @Secrop 's Tools for Cycles Pynodes, but we still wouldn’t know how to work that out.