Custom Entity

[gswifort]

Can I create custom types inheriting from Db.Entity that will write additional data to the dwg database. I see the .dwgOutFields() method in ARX, but I don't see it in PyRx.

[CEXT-Dan]

Unfortunately, no. The goal is to be able to simulate one with overrules, but I only have ObjectOverrule and DrawableOverrule, though this is usually enough for most.

I’ve thought about some different options, such as making a couple of base custom objects that could be extended or overruled. I also need to consider if someone wants to add in a C++/Python custom object. As of now, the only way to do this is fork the project

Is this for something specific? Maybe I can recommend an approach. BTW, you can examine the contents of dwgOutFields with the snoop filer, see testDbObjectSnoop sample

[CEXT-Dan]

one option would be to use a selection set filter

def PyRxCmd_doit3() -> None:
    try:
        filter = [(Db.DxfCode.kDxfXDataStart, 0),
            (Db.DxfCode.kDxfRegAppName, "PYTHONTEST")]
        ss = Ed.Editor.selectAll(filter)
        print(len(ss[1].objectIds()))
    except Exception as err:
        traceback.print_exception(err)

[gswifort]

I will be grateful for the above example also with Xrecord. As I understand, then I will not have data size limitation like in Xdata.

[CEXT-Dan]

I probably didn’t explain this well enough. the 127-byte limit is the maximum chunk size
This is both Xrecord and Xdata, Xdata itself will hold like 16kb

i've revised my sample

[CEXT-Dan]

Oh I found something even cooler! this creates an Xrecord

import traceback
from pyrx_imp import Rx, Ge, Gi, Db, Ap, Ed
import pickle

class PyData:
    sd1 = ""
    sd2 = ""
    fd1 = 0.0
    id1 = 1

    def printData(self):
        print("\n{}\n{}\n{}\n{}".format(self.sd1,self.sd2,self.fd1,self.id1))

def PyRxCmd_doit() -> None:
    try:
        esres = Ed.Editor.entSel("\nSelect: ")
        if esres[0] != Ed.PromptStatus.eOk:
            raise RuntimeError("Entsel Error {}: ".format(esres[0]))

        data = PyData()
        data.sd1 = "check out the brain on brad, lets make this bigger than 127 bytes"
        data.sd2 = "check out the brain on brad, lets make this bigger than 127 bytes"
        data.fd1 = 3.14159265359
        data.id1 = 42
        
        ent = Db.Entity(esres[1], Db.OpenMode.kForWrite)
        ent.setBinaryData("PYTHONTEST", pickle.dumps(data))
        
    except Exception as err:
        traceback.print_exception(err)

def PyRxCmd_doit2() -> None:
    try:
        esres = Ed.Editor.entSel("\nSelect: ")
        if esres[0] != Ed.PromptStatus.eOk:
            raise RuntimeError("Entsel Error {}: ".format(esres[0]))
        
        ent = Db.Entity(esres[1])
        bOut = ent.getBinaryData("PYTHONTEST")
        data = pickle.loads(bOut)
        
        data.printData()
        
    except Exception as err:

[CEXT-Dan]

I added functions setXDBinaryData and getXDBinaryData that will behave exactly like setBinaryData and getBinaryData shown above, but it's xdata.. I'll post a sample

[CEXT-Dan]

getBinaryData, setBinaryData fail on ZwCAD, pass on AutoCAD, BricsCAD and GstarCAD
getXDBinaryData, setXDBinaryData works on all

[CEXT-Dan]

getBinaryData, setBinaryData getXDBinaryData, setXDBinaryData now pass all platforms

[gswifort]

As I understand it, obj.setBinaryData() adds an Xrecord object to the database and assigns it an obj id as a parent. Could this method return the id of the Xrecord object so that nested structures can be created?

xr1 = Db.Xrecord(ent.setBinaryData(...))
xr2 = Db.Xrecord(xr1.setBinaryData(...))
xr3 = Db.Xrecord(xr2.setBinaryData(...))

[CEXT-Dan]

Yes, I can try to make setBinaryData return the objectId of the Xrecord

However, if you notice the picture I posted, obj.setBinaryData creates a Dictionary with the obj as its parent,
then adds an entry [KEY, Xrecord]. the owner of the Xrecord is the Dictionary. So, you can already store multiple Xrecords per entity.

I think with the nested approach, it may be difficult to query if the object has nested data, and creating a lot of dictionaries with one entry.