draw_cad.py

#!/usr/bin/env python3
# Copyright (c) 2020-2023, Matthew Broadway
# License: MIT License
import argparse
import sys

import matplotlib.pyplot as plt

import ezdxf
from ezdxf import recover
from ezdxf.addons.drawing import RenderContext, Frontend
from ezdxf.addons.drawing.matplotlib import MatplotlibBackend
from ezdxf.addons.drawing.config import Configuration

# ------------------------------------------------------------------------------
# The "draw_cad.py" viewer can be executed by the new ezdxf command line
# launcher:
#
# C:\> ezdxf draw FILE
#
# This file remains as an example for the usage of the Matplotlib backend.
#
# docs: https://ezdxf.mozman.at/docs/addons/drawing.html
# ------------------------------------------------------------------------------


def _main():
    parser = argparse.ArgumentParser(
        description="draw the given CAD file and save it to a file or view it"
    )
    parser.add_argument("cad_file", nargs="?")
    parser.add_argument("--supported_formats", action="store_true")
    parser.add_argument("-l", "--layout", default="Model")
    parser.add_argument("--out", required=False)
    parser.add_argument("--dpi", type=int, default=300)
    args = parser.parse_args()

    if args.supported_formats:
        fig = plt.figure()
        for (
            extension,
            description,
        ) in fig.canvas.get_supported_filetypes().items():
            print(f"{extension}: {description}")
        sys.exit()

    if args.cad_file is None:
        print("no CAD file specified")
        sys.exit(1)

    try:
        doc = ezdxf.readfile(args.cad_file)
    except IOError:
        print(f"Not a DXF file or a generic I/O error.")
        sys.exit(2)
    except ezdxf.DXFError:
        try:
            doc, auditor = recover.readfile(args.cad_file)
        except ezdxf.DXFStructureError:
            print(f"Invalid or corrupted DXF file: {args.cad_file}")
            sys.exit(3)
    else:
        auditor = doc.audit()

    if auditor.has_errors:
        # But is most likely good enough for rendering.
        print(f"Found {len(auditor.errors)} unrecoverable errors.")
    if auditor.has_fixes:
        print(f"Fixed {len(auditor.fixes)} errors.")

    try:
        layout = doc.layouts.get(args.layout)
    except KeyError:
        print(
            f'Could not find layout "{args.layout}". '
            f"Valid layouts: {[l.name for l in doc.layouts]}"
        )
        sys.exit(4)

    # setup drawing add-on configuration
    config = Configuration()
    fig: plt.Figure = plt.figure(dpi=args.dpi)
    ax: plt.Axes = fig.add_axes([0, 0, 1, 1])
    ctx = RenderContext(doc)
    out = MatplotlibBackend(ax)
    Frontend(ctx, out, config=config).draw_layout(layout, finalize=True)
    if args.out is not None:
        print(f'saving to "{args.out}"')
        fig.savefig(args.out, dpi=args.dpi)
        plt.close(fig)
    else:
        plt.show()


if __name__ == "__main__":
    _main()