Vibe coding using PyRx

[schoeller]

Dear all,

I am fumbling about with vibe coding in order to widen my horizon. The idea is to hand input/output information and to have scripts in between being generated.
Starting out with Mistral Vibe. Am trying steps as below

1#Studying API (https://cext-dan.github.io/CADPyRxDoc/)
2#Study examples (https://github.com/CEXT-Dan/PyRx/tree/main/PySamples)
3#Ask for examples and improve iteratively script through error messages
...
X#(Maybe) study sample project (https://github.com/gswifort/PyRx-sample-project)

A headless mode with output to the vibe environment would be useful. I do not know of any headless setups.
Hints and experiences are appreciated.

Best

Seb

[CEXT-Dan]

I’ve been thinking about this. Unfortunately, ARX/BRX, and by extension PyRx, must run in process. This makes it difficult for models to interact with CAD. I have no idea how an agent can interact with CAD effectively.

You can run BricsCAD headless by using something like /automation /B <path>/scriptFileName.scr. Or you could possibly use win32com or PyAutoCAD to launch CAD and run PyRx commands via send string to execute.

Some people have started working on AutoCAD MCP Servers. Maybe one could be modified to run PyRx scripts

Fine tuning. I noticed that people are fine tuning models, I’ve seen one of the Qwen models fine-tuned for Python, which got me thinking about fine tuning one of the models for PyRx. it would require a hefty video card to run though

So far the best local model for programming in CAD is GLM 4.7 Flash. It can one shot these prompts

Please write a function in C++, ObjectARX for AutoCAD, that gets all the object ids from block table record, model space
Please write a function in Autolisp for AutoCAD, that moves all the entities in modelspace, in the x direction, by 100 units. Please use vlax-tmatrix and vla-transformby

Finally. I’ve had really good results by uploading .PYI files to the model. I’ve been thinking about making some amalgamation of the .PYI files, however, I don’t know if the model will lose PyDb vs PyGe context. if Mistral Vibe has RAG, I would definitely start by uploading the stubs.

[CEXT-Dan]

A Warning about using LLMs for CAD, LLMs are trained on text. Pattern matching and predicting the next word. They have zero spatial awareness. I noticed this when playing around with a bounded plane. I would create a rotated bounded plane, all of the models stumbled creating a line to intersect.

Probably the reason for the crazy clocks

[schoeller]

@CEXT-Dan
Have Vibe + Devstral-small-2 running on Ollama locally. Communication with Vibe is as follows:

Me:

please study the python stub files in the folder "C:\Users\XXYYZZ\Documents\GitHub\PyRx\pyrx"

Devstral:

Working...

Me:

when you finished studying, please develop a code sample for the following task "Please write a function PyRx for AutoCAD, that gets all the object ids from block table record, model space" and write it to the file "C:\Users\XXYYZZ\Downloads\test.py"

Devstral:

import win32com.client

def PyRx():
    """
    Function to get all object IDs from block table record in AutoCAD model space
    Returns a list of object IDs
    """
    try:
        # Initialize AutoCAD application
        acad = win32com.client.Dispatch("AutoCAD.Application")
        doc = acad.ActiveDocument
        
        # Get the block table
        block_table = doc.Database.BlockTable
        
        # Get the model space block table record
        model_space = block_table.Item(acad.constants.acBlockTableRecord)
        
        # Get all objects in model space
        objects = model_space.GetObjects()
        
        # Extract object IDs
        object_ids = [obj.ObjectId for obj in objects]
        
        return object_ids
        
    except Exception as e:
        print(f"Error: {e}")
        return []

# Example usage
if __name__ == "__main__":
    ids = PyRx()
    print(f"Number of objects: {len(ids)}")
    print(f"First 5 object IDs: {ids[:5]}")

If you could share your approaches on how to specify communication more effectively I'd be glad.

Best

Seb

[schoeller]

Me:

please improve the sample not using win32com.client, but only pyrx library

Devstral:

from pyrx import rx

def PyRx():

    """
    Function to get all object IDs from block table record in AutoCAD model space
    Returns a list of object IDs
    """
    try:
        # Get the current document
        doc = rx.get_doc()
        
        # Get the block table
        block_table = doc.block_table
        
        # Get the model space block table record
        model_space = block_table[0]  # Model space is index 0
        
        # Get all objects in model space
        objects = list(model_space)
        
        # Extract object IDs
        object_ids = [obj.handle for obj in objects]
        
        return object_ids
        
    except Exception as e:
        print(f"Error: {e}")
        return []

# Example usage
if __name__ == "__main__":
    ids = PyRx()
    print(f"Number of objects: {len(ids)}")
    print(f"First 5 object IDs: {ids[:5]}")

[CEXT-Dan]

I found the local models do better with help, I.e. with a sample command and the imports. They’re not good enough for agentic work yet, but are really good at helping you fill in the blanks. I’m still working on my prompting, sometimes I say “you may take inspiration from C++ ObjectARX since CAD-PyRx is a wrapper”

devstral-small-2-24b-instruct-2512 in LM studio

[CEXT-Dan]

the corrected code

        db = Db.curDb()
        model_space_id = Db.SymUtilServices().blockModelSpaceId(db)
        model_space = Db.BlockTableRecord(model_space_id)
        for obj_id in model_space:
            print(obj_id)

[CEXT-Dan]

Side note, I plan on fine tuning one of the models with PyRx, maybe I’ll give it a go sometime this summer, I need lots of samples and synthetic data. I'm thinking one of the 30b sized models. though I can try a 8b