Compute file complexity

[mgohin]

Hi,

I'm using ezdxf to convert DXF file to image from anyone around me, and there are files way too complex to convert it in a reasonable time (let's say less than 2 minutes).

Is there any way to compute something like a complexity indice, or analyse file to know that some part will be very long to draw ?

Thanks in advance for your answers :)

PS: Thanks for this easy to use tool ❤️ open source community ❤️

[mozman]

The only heuristic i can think of is to count the DXF entities recursively for a layout like the modelspace.

import ezdxf
from ezdxf.layouts import BaseLayout

def count_entities(layout: BaseLayout) -> int:
    """Counts the DXF entities in the given layout recursively.
    
    This is not an exact count, not include are:
        - DIMENSION geometry block
        - ACAD_TABLE geometry block
        - XREF content
        - multiplied INSERT entities
        - ...

    """
    count = len(layout)
    doc = layout.doc
    if doc is None:
        return count
    for insert in layout.query("INSERT"):
        block = insert.block()
        if block:
            count += count_entities(block)
    return count

def main():
    doc = ezdxf.readfile("big.dxf")
    print(count_entities(doc.modelspace()))


if __name__ == "__main__":
    main()

Often is loading such a big file already a problem, so a size check is maybe also a good idea.

Don't ask for a reasonable size limit, this depends on your system - modern workstation with 128 GB RAM and fast NVMe vs old potato notebook with 8GB RAM and a HDD.

[mgohin]

Thanks, I'm gonna try this :)