How do I get reference to the principle bsdf if it's inside a node group?

Coding Beginning Blender Code and Development
1

If I have n number of node group how do I find the principle bsdf?

2

What do you mean by find the Principled-BSDF ??

A node group might not have any Principled BSDF included at all. And you can open any node group with the Tab key.

3

It’s a question in the Coding subcategory, so I imagine they’re asking how to find a reference to the Principled node via Python.

1 Like
4

I would also say we need a bit more information about what you’re trying to do exactly, because it’s fairly straightforward to get access to a principled node, but getting access to a specific one in a specific group is a bit different, so we might need to know more about what you’re aiming for.

5

Indeed i overlooked this… anyway: What ? :wink:

1 Like
6

i pretty much need to check the different input values of principled node regardless of which node group it is located in

7

Provided you have some material and know the name of the Principled node:

def get_node(tree,node_name):
    return tree.nodes.get(node_name)

#mat: bpy.types.Material 
#some_shadernodegroup_node_name: str
#name_of_your_principled_node:str
mat_nodes = mat.node_tree.nodes
group_node = mat_nodes.get(some_shadernodegroup_node_name)
princ_node = get_node(group_node.node_tree, name_of_your_principled_node)

Or, if you want to find every Principled node inside a node tree:

def find_all_princ_nodes(tree):
    return [n for n in tree.nodes if n.type == 'BSDF_PRINCIPLED']

Hope this will help you

2 Likes
8

that’s not my question. my question was how do i get reference to principle bsdf if it’s located in a node group

9

Okay, so you don’t know which tree the principle node is in? You can use the functions above to create a recursive function. I modified the find_all function to return all node groups inside a tree.

def find_all_group_nodes(tree):
    return [n for n in tree.nodes if n.type == 'GROUP']

def find_princ_node(tree,name):
    princ_node = get_node(tree,name)
    if  princ_node: 
        return princ_node
    for group in find_all_group_nodes(tree):
        princ_node = find_princ_node(group.node_tree,name)
        if princ_node:
            return princ_node
    return None
10

Exactly what I needed thanks