Python generator

james.thamesview

I am using a python generator to produce sets of splines. I want the code to check the python generator object for a hair tag. Then I want to get the underlying hair material colour gradient and use that as the basis for customer hair textures to be applied to the splines
this is a snippet of what I have so far (mainly using copilot to help me)
for tag in op.GetTags():

        #print (tag,tag.GetType())
            if tag.GetType() == c4d.Thairmaterial:
                material_tag = tag
                material = material_tag.GetMaterial()
                source_gradient = material[c4d.HAIR_MATERIAL_COLOR_GRADIENT]
                gradient = hair_material[c4d.HAIR_MATERIAL_COLOR_GRADIENT]
                for i in range(gradient.GetKnotCount()):
                    knot = gradient.GetKnot(i)
                    print(f"Knot {i}: Color = {knot.col}, Position = {knot.pos}")     
        
        break

This fails with "AttributeError: 'c4d.BaseTag' object has no attribute 'GetMaterial' "
It looks to me like python is not seeing tag as a Hair material and/or I am calling the wrong method to get the underlying material.
So two questions:
1: how do I correct this
2: what should I be searching for in the docs to be able to work this out for myself

Thanks in advance

Regards

Jim

i_mazlov

Hi Jim.

Thanks for reaching out to us! According to our Support Procedures:

We cannot provide support for the side-effects of unexperienced users using AI models to write code.

Your code contains multiple issues that were likly hallutinated by AI tool you're using:

There's no such function "GetMaterial()" on the hair material tag
There's no such ID c4d.HAIR_MATERIAL_COLOR_GRADIENT (it's c4d.HAIRMATERIAL_COLOR_GRADIENT)
The GetKnot() returns you not a class instance rather a dictionary, so accessing its content is performed by using the subscript operator rather than dot operator.

I would also suggest you reading through the following manuals, which I supposed would be of great use for you:
How to get/set parameters using Drag&Drop
How to use Visual Studio Code Integration

Using the VSCode integration allows you to use syntax highlight as well as IntelliSense, which would immediately give you hints on the correct usage of functions and methods, as well as an in-place documentation.

Please find the suggested code snipet for your problem below.

Cheers,
Ilia

Code snippet for the Script Manager:

import c4d, mxutils

doc: c4d.documents.BaseDocument  # The currently active document.
op: c4d.BaseObject | None  # The primary selected object in `doc`. Can be `None`.

def main() -> None:
    # Find hair tag on the active object
    tag = mxutils.CheckType(op.GetTag(c4d.Thairmaterial), c4d.BaseTag)
    # Retrieve the linked material
    material = mxutils.CheckType(tag[c4d.HAIRMATERIAL_TAG_LINK], c4d.BaseMaterial)
    # Retrieve the gradient attribute
    gradient = mxutils.CheckType(material[c4d.HAIRMATERIAL_COLOR_GRADIENT], c4d.Gradient)
    # Iterate gradient knots
    for i in range(gradient.GetKnotCount()):
        print(gradient.GetKnot(i))

if __name__ == '__main__':
    main()
    c4d.EventAdd()

james.thamesview

@i_mazlov
Thanks for your help. I using visual studio code as you suggested and am getting to grips with the Drag and Drop to assist with parameter getting and setting.