import ezdxf
from ezdxf import path

# 创建 DXF 文档
doc = ezdxf.new(dxfversion='R2018')
msp = doc.modelspace()

# 定义填充边界
boundary_points = [(0, 0), (50, 0), (50, 30), (0, 30)]

# 创建 HATCH 实体
hatch = msp.add_hatch(color=1)
hatch.set_pattern_fill(name='GRAVEL', scale=0.5, angle=45)

# 新版本直接添加多段线路径，无需 flags 参数
hatch.paths.add_polyline_path(
    boundary_points,
    is_closed=True  # 只需确保闭合即可
)

doc.saveas("hatch_example.dxf")