Yes, download the SDK and study the examples.
I wrote my own software that allows me to simply select the type of plugin I want to create, enter the plugin ID and the plugin name. The program then creates the folder structure, all files with the correct content and the correct name automatically...that was the first thing I did because it is always extremely tedious.
This then takes 10 seconds and I have a finished blueprint. Then I can start programming straight away.
I usually make the Gui first using UserData to roughly create the design and then I write it down in the resfile in no time at all. It's relatively quick and even fun and you gradually grow into it, it emerges little by little.....

Basically it wouldn't be a problem to write a script that writes the UserData interface into a Res, header and string file, I already have an idea for that... That would actually be easy to do.
I'll get to it when I'm done with my update... and then maybe make it available to the community... However, a similar one is already there, but I can't remember where.

Greetings
Tom

@ferdinand
Hello Ferdinand,
Thank you very much first of all.
yes, you're right, I worked extremely sloppily with the SMC method, of course I'll take the threading into account and also work with a Temp Document.

Regarding the problem itself, I can only say that reinstalling CINEMA 4D solved our problem.

Cheers

@ferdinand
oh man thanks I forgot this

BaseDocument.ExecutePasses(bt=None, animation=False, expressions=False, caches=True, flags=c4d.BUILDFLAGS_NONE)

I tried that before but it seems I have set the caches parameter wrong.
Thank you very much....

@ferdinand
Thank you for your detailed explanation, it shed some light on the whole matter for me.

Apologies in advance if this question is out of scope.
Is the Maxon API already fully usable for Python, or can it completely replace the classic API? I find it very difficult to understand right now. Or is it more intended for initializing data types and using it in conjunction with the classic API?
And if not, when will it finally be fully usable for Python?

@i_mazlov
Thank you very much for the hint with the texture view and for the helpful links.
The second thread I have already read, but was not able to find the solution so far. I study these examples. Thank you.

Hi,
I am not able to get the TempUVHandle from an active UVWTag in R21.
It returns always "None".
In the following script I created a simple plane in a TempDoc and took the cache and inserted it into the TempDoc. It already has a UVW-Tag, then I have set the object active and so the UVWTag....

My Code:

import c4d

def main():
    temp = c4d.documents.BaseDocument()

    plane = c4d.BaseObject(c4d.Oplane)
    temp.InsertObject(plane)
    temp.ExecutePasses(bt=None, animation=False, expressions=False, caches=True, flags=c4d.BUILDFLAGS_NONE)
    
    plane_cache = plane.GetCache().GetClone()

    if plane_cache is None:
        raise Exception("no cache")

    temp.InsertObject(plane_cache)
    uvw_tag = plane_cache.GetTag(c4d.Tuvw)   
    temp.SetActiveTag(uvw_tag)
    temp.SetActiveObject(plane_cache)

    handle = c4d.modules.bodypaint.GetActiveUVSet(temp, c4d.GETACTIVEUVSET_UVWS)
    
    print(handle)
    

# Execute main()
if __name__=='__main__':
    main()

@ferdinand
Thanks a lot Ferdinand for your time and effort. It is always admirable how carefully and thoroughly you answer many questions.
At first it was often difficult to understand and follow your code examples...now it is a little easier.
Thanks for that.

I found out that the following method also does the job:

c4d.SendCoreMessage(c4d.COREMSG_CINEMA, c4d.BaseContainer(c4d.COREMSG_CINEMA_FORCE_AM_UPDATE), 0)

Sorry for the second question about why this

buttonDesc[c4d.DESC_FITH] = True
buttonDesc[c4d.DESC_SCALEH] = True

in the GetDDescription method are not working. I thought this is a follow-up question.
I will open another topic for that.

Hi, in my object plugin it worked fine but in my tag plugin the description cannot be updated after clicking a button which in this example should add a new button.

so when I click the button it adds a new id to the member variable self.id_list, and then I iter through this list in my GetDDescription() method
It just shows the added Button if I click on the Object which holds the tag and select again the tag.
Do I have to send a message? I read the GitHubExample but it is a example with an ObjectPlugin.

import c4d
from c4d import bitmaps, gui, plugins

# Just a test ID
PLUGIN_ID = 1110101

PY_ADD_TRACK = 10000

#The Plugin Class
class Audioworkstation(plugins.TagData):
    def __init__(self):
        self.id_list = []

    def Init(self, node):       
        return True   

    def GetDDescription(self, op, description, flags):       
        if not description.LoadDescription(op.GetType()):
            return False
        singleID = description.GetSingleDescID()

        # id_counter = 1
        for desc_id in reversed(self.id_list):
           
            measure_object_hide = c4d.DescID(c4d.DescLevel(desc_id + 2, c4d.DTYPE_BUTTON, op.GetType()))
            if not singleID or measure_object_hide.IsPartOf(singleID)[0]:
                bc_measure_object_hide = c4d.GetCustomDataTypeDefault(c4d.DTYPE_BUTTON)
                bc_measure_object_hide[c4d.DESC_NAME] = "DELETE"
                bc_measure_object_hide[c4d.DESC_CUSTOMGUI] = c4d.CUSTOMGUI_BUTTON
                # id_counter += 1
                if not description.SetParameter(measure_object_hide, bc_measure_object_hide, c4d.DescID(c4d.DescLevel(
                                                    c4d.ID_TAGPROPERTIES))):
                    return False

        return True, flags | c4d.DESCFLAGS_DESC_LOADED

    def Execute(self, tag, doc, op, bt, priority, flags):
        return c4d.EXECUTIONRESULT_OK

    def Message(self, node, type, data):

        if type == c4d.MSG_DESCRIPTION_COMMAND:
            if data["id"][0].id == PY_ADD_TRACK:
               
                last_id = None
                if self.id_list:
                    last_id = self.id_list[-1]
                    new_id = last_id + 100
                    self.id_list.append(new_id)
                else:
                    new_id = 10100
                    self.id_list.append(new_id)
                node.Message(c4d.MSG_CHANGE)                

        return True

# main
if __name__ == "__main__":    
    bmp = bitmaps.BaseBitmap()
    dir, file = os.path.split(__file__)
    fn = os.path.join(dir, "res", "icon.tif")
    bmp.InitWith(fn)
    
    c4d.plugins.RegisterTagPlugin(id=PLUGIN_ID,
                                  str="C4D-Audioworkstation",
                                  info=c4d.TAG_EXPRESSION | c4d.TAG_VISIBLE,
                                  description="audioworkstation",
                                  g=Audioworkstation, icon=bmp)

edit by @ferdinand:

@ThomasB said:

I have also problems to scale the button so that it fits the attribute manager:

so this doesn't work in the GetDDescription Example above:

bc_measure_object_hide[c4d.DESC_SCALEH] = True
bc_measure_object_hide[c4d.DESC_FITH] = True

@ferdinand
this is really odd, because I have a Button in my plugin which simply creates keyframes for specific description parameters of the plugin, similar as it is in the PoseMorph Tag when you create keyframes for all sliders at once. And here it works without crashing:
Maybe this helps you.
The code of writing the keyframes is pretty the same, the only difference is that I set here keyframes for the description Id's instead of the user-datas...hm

this is just a snippet:

PY_STRENGTH_A_MANUAL = 10051
PY_STRENGTH_E_MANUAL = 10052
PY_STRENGTH_I_MANUAL = 10053
PY_STRENGTH_O_MANUAL = 10054
PY_STRENGTH_U_MANUAL = 10055
PY_STRENGTH_F_MANUAL = 10056
PY_STRENGTH_W_MANUAL = 10057
PY_STRENGTH_SH_MANUAL = 10058
PY_STRENGTH_OTHERS_MANUAL = 10059
PY_STRENGTH_CLOSED_MANUAL = 10060

id_list = [PY_STRENGTH_A_MANUAL,
           PY_STRENGTH_E_MANUAL,
           PY_STRENGTH_I_MANUAL,
           PY_STRENGTH_O_MANUAL,
           PY_STRENGTH_U_MANUAL,
           PY_STRENGTH_F_MANUAL,
           PY_STRENGTH_W_MANUAL,
           PY_STRENGTH_SH_MANUAL,
           PY_STRENGTH_OTHERS_MANUAL,
           PY_STRENGTH_CLOSED_MANUAL
           ]
#========Plugin====================
        def Message(self, node, type, data):
            if data["id"][0].id == PY_RECORD_MANUAL:

                time = node.GetObject().GetDocument().GetTime()
                node.GetDocument().AddUndo(c4d.UNDOTYPE_CHANGE, node)
                if c4d.threading.GeIsMainThread():
                    for ide in id_list:

                        track = node.FindCTrack(ide)

                        if not track:
                            track = c4d.CTrack(node, ide)
                            node.InsertTrackSorted(track)

                        curve = track.GetCurve(c4d.CCURVE_CURVE, True)

                        keydata = curve.AddKey(time)
                        if keydata is None:
                            raise RuntimeError("Could not add key frame.")

                        key = keydata["key"]
                        key.SetValue(curve, node[ide])
                        key[c4d.ID_CKEY_PRESET] = 2  # c4d.ID_CKEY_PRESET_AUTO_OVERSHOOTWEIGHTED

                c4d.EventAdd()

Hello,

I'm just a bit stumped. In previous versions of C4D this approach, writing keys worked perfectly.
Normally the routine is executed by a plugin in the message method, but I was able to change the example into a script and that's where the error occurs.

Here I have the script and the required scene with the object.
bake_test.zip

The script should simply write keys with values ​​into the user data, usually the user datas are animated and they are a lot more, so in the plugin it has to filter the right ones
After detailed debugging, I'm sure the error happens in the third last line with key.SetValue(curve, value)

import c4d

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

def bake():

    strength_list = {
        "AA": 1,
        "EE": 1,
        "IY": 1,
        "OW": 1,
        "UW": 1,
        "F": 1,
        "W": 1,
        "SH": 1,
        "T": 1,
        "M": 1
    }

    after_list = []

    # =================================================

    user_list = ["AA", "EE", "IY", "OW", "UW", "F", "W", "SH", "T", "M"]

    parameter_list = []

    for ide, bc in op.GetUserDataContainer():
        if bc[c4d.DESC_NAME] in user_list:
            parameter_list.append(ide)
            after_list.append(bc[c4d.DESC_NAME])

    if not parameter_list:  # if no userdatas added
        c4d.gui.MessageDialog("Missing User Datas!\n\nClick 'Add User-Data'")
        return True

    doc.AddUndo(c4d.UNDOTYPE_CHANGE, op)
    c4d.StatusSetSpin()
    # start = node[PY_BAKE_START]
    # end = node[PY_BAKE_END]

    for frame in range(0, 90):

        time = c4d.BaseTime(frame, doc.GetFps())

        doc.SetTime(time)

        doc.ExecutePasses(None, True, True, True,
                          c4d.BUILDFLAGS_NONE)  # False True False

        for ide in parameter_list:
            track = op.FindCTrack(ide)

            if track is None:
                track = c4d.CTrack(op, ide)
                op.InsertTrackSorted(track)

            curve = track.GetCurve()
            keyData = curve.AddKey(time)

            if keyData is None:
                raise RuntimeError("Could not add key frame.")

            key = keyData["key"]

            key.SetValue(curve, op[ide])

            key[c4d.ID_CKEY_PRESET] = 2  # c4d.ID_CKEY_PRESET_AUTO_OVERSHOOTWEIGHTED

    c4d.StatusClear()

def main() -> None:
    """Called by Cinema 4D when the script is being executed.
    """
    bake()


if __name__ == '__main__':
    main()

Cheers

An Object plugin returns an object chain with certain objects.
But now I need a point at a very specific position of the object where other objects created in Cinema 4D can snap to it.

I have or rather wanted to solve this by creating an internal polygon object that is placed in the object chain with a point, for example. I then made the point visually visible using the Draw method

ObjectData.Draw(self, op, drawpass, bd, bh)

However, the snapping does not work properly. If you're too close, nothing will snap. If the snapping radius is too small, nothing works.
Am I completely on the wrong track or should I approach the whole thing differently? Sometimes there's just a lack of new things, and I can't always find everything in the Github examples...sometimes I have to laugh at myself, how stupid I want to start a spedific approach....

Regards

@ferdinand
oh man thanks I forgot this

BaseDocument.ExecutePasses(bt=None, animation=False, expressions=False, caches=True, flags=c4d.BUILDFLAGS_NONE)

I tried that before but it seems I have set the caches parameter wrong.
Thank you very much....