Mimic UDIM in Cinema4D

udim.py

import re, c4d
from c4d import documents as docs

# Python tag that Mimics UDIM for texture tags in Cimena4D.
# Name your texture tags 1001, 1002, 1021 etc
# Doesn't check the number of tag on each row
# Iterates through all tags on the object that this script is attached to
# Find all texture tags with with name that starts with 10 (UDIM style)
# Check if they are of type texture (5616)

class TagIterator:
    def __init__(self, obj):
        currentTag = None
        if obj :
            self.currentTag = obj.GetFirstTag()

    def __iter__(self):
        return self

    def next(self):
        tag = self.currentTag
        if tag == None :
            raise StopIteration

        self.currentTag = tag.GetNext()
        return tag

def main():
    obj = op.GetObject()

    tags = TagIterator(obj)
    
    for tag in tags:
        # Check first if tag type is Texture     
        if tag.GetType() == 5616:
            # Then check if Tag name starts with 10
            if tag[c4d.ID_BASELIST_NAME][:2] == "10":
                # Take the 4th character and subtract 1 to get U
                offsetU = float(tag[c4d.ID_BASELIST_NAME][3]) - 1.0
                
                # Take the 3rd character and multiply with -1 to get V
                offsetV = float(tag[c4d.ID_BASELIST_NAME][2]) * -1
                
                # print "Offset U %s" % tag[c4d.TEXTURETAG_OFFSETX]
                # print "Offset V %s" % tag[c4d.TEXTURETAG_OFFSETY]
                
                # Set U and V
                tag[c4d.TEXTURETAG_OFFSETX] = offsetU
                tag[c4d.TEXTURETAG_OFFSETY] = offsetV