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stepanalyser/.venv/lib/python3.12/site-packages/ezdxf/entities/circle.py
Christian Anetzberger a197de9456 initial
2026-01-22 20:23:51 +01:00

215 lines
7.5 KiB
Python

# Copyright (c) 2019-2024 Manfred Moitzi
# License: MIT License
from __future__ import annotations
from typing import TYPE_CHECKING, Iterable, Optional, Iterator
import math
import numpy as np
from ezdxf.lldxf import validator
from ezdxf.math import (
Vec3,
Matrix44,
NULLVEC,
Z_AXIS,
arc_segment_count,
)
from ezdxf.math.transformtools import OCSTransform, NonUniformScalingError
from ezdxf.lldxf.attributes import (
DXFAttr,
DXFAttributes,
DefSubclass,
XType,
RETURN_DEFAULT,
group_code_mapping,
merge_group_code_mappings,
)
from ezdxf.lldxf.const import DXF12, SUBCLASS_MARKER, DXFValueError
from .dxfentity import base_class, SubclassProcessor
from .dxfgfx import (
DXFGraphic,
acdb_entity,
add_entity,
replace_entity,
elevation_to_z_axis,
acdb_entity_group_codes,
)
from .factory import register_entity
if TYPE_CHECKING:
from ezdxf.entities import DXFNamespace
from ezdxf.lldxf.tagwriter import AbstractTagWriter
from ezdxf.entities import Ellipse, Spline
__all__ = ["Circle"]
acdb_circle = DefSubclass(
"AcDbCircle",
{
"center": DXFAttr(10, xtype=XType.point3d, default=NULLVEC),
# AutCAD/BricsCAD: Radius is <= 0 is valid
"radius": DXFAttr(40, default=1),
# Elevation is a legacy feature from R11 and prior, do not use this
# attribute, store the entity elevation in the z-axis of the vertices.
# ezdxf does not export the elevation attribute!
"elevation": DXFAttr(38, default=0, optional=True),
"thickness": DXFAttr(39, default=0, optional=True),
"extrusion": DXFAttr(
210,
xtype=XType.point3d,
default=Z_AXIS,
optional=True,
validator=validator.is_not_null_vector,
fixer=RETURN_DEFAULT,
),
},
)
acdb_circle_group_codes = group_code_mapping(acdb_circle)
merged_circle_group_codes = merge_group_code_mappings(
acdb_entity_group_codes, acdb_circle_group_codes
)
@register_entity
class Circle(DXFGraphic):
"""DXF CIRCLE entity"""
DXFTYPE = "CIRCLE"
DXFATTRIBS = DXFAttributes(base_class, acdb_entity, acdb_circle)
MERGED_GROUP_CODES = merged_circle_group_codes
def load_dxf_attribs(
self, processor: Optional[SubclassProcessor] = None
) -> DXFNamespace:
"""Loading interface. (internal API)"""
# bypass DXFGraphic, loading proxy graphic is skipped!
dxf = super(DXFGraphic, self).load_dxf_attribs(processor)
if processor:
processor.simple_dxfattribs_loader(dxf, self.MERGED_GROUP_CODES)
if processor.r12:
# Transform elevation attribute from R11 to z-axis values:
elevation_to_z_axis(dxf, ("center",))
return dxf
def export_entity(self, tagwriter: AbstractTagWriter) -> None:
"""Export entity specific data as DXF tags."""
super().export_entity(tagwriter)
if tagwriter.dxfversion > DXF12:
tagwriter.write_tag2(SUBCLASS_MARKER, acdb_circle.name)
self.dxf.export_dxf_attribs(
tagwriter, ["center", "radius", "thickness", "extrusion"]
)
def vertices(self, angles: Iterable[float]) -> Iterator[Vec3]:
"""Yields the vertices of the circle of all given `angles` as
:class:`~ezdxf.math.Vec3` instances in :ref:`WCS`.
Args:
angles: iterable of angles in :ref:`OCS` as degrees, angle goes
counter-clockwise around the extrusion vector, and the OCS x-axis
defines 0-degree.
"""
ocs = self.ocs()
radius: float = abs(self.dxf.radius) # AutoCAD ignores the sign too
center = Vec3(self.dxf.center)
for angle in angles:
yield ocs.to_wcs(Vec3.from_deg_angle(angle, radius) + center)
def flattening(self, sagitta: float) -> Iterator[Vec3]:
"""Approximate the circle by vertices in :ref:`WCS` as :class:`~ezdxf.math.Vec3`
instances. The argument `sagitta`_ is the maximum distance from the center of an
arc segment to the center of its chord. Yields a closed polygon where the start
vertex is equal to the end vertex!
.. _sagitta: https://en.wikipedia.org/wiki/Sagitta_(geometry)
"""
radius = abs(self.dxf.radius)
if radius > 0.0:
count = arc_segment_count(radius, math.tau, sagitta)
yield from self.vertices(np.linspace(0.0, 360.0, count + 1))
def transform(self, m: Matrix44) -> Circle:
"""Transform the CIRCLE entity by transformation matrix `m` inplace.
Raises ``NonUniformScalingError()`` for non-uniform scaling.
"""
circle = self._transform(OCSTransform(self.dxf.extrusion, m))
self.post_transform(m)
return circle
def _transform(self, ocs: OCSTransform) -> Circle:
dxf = self.dxf
if ocs.scale_uniform:
dxf.extrusion = ocs.new_extrusion
dxf.center = ocs.transform_vertex(dxf.center)
# old_ocs has a uniform scaled xy-plane, direction of radius-vector
# in the xy-plane is not important, choose x-axis for no reason:
dxf.radius = ocs.transform_length((dxf.radius, 0, 0))
if dxf.hasattr("thickness"):
# thickness vector points in the z-direction of the old_ocs,
# thickness can be negative
dxf.thickness = ocs.transform_thickness(dxf.thickness)
else:
# Caller has to catch this Exception and convert this
# CIRCLE/ARC into an ELLIPSE.
raise NonUniformScalingError(
"CIRCLE/ARC does not support non uniform scaling"
)
return self
def translate(self, dx: float, dy: float, dz: float) -> Circle:
"""Optimized CIRCLE/ARC translation about `dx` in x-axis, `dy` in
y-axis and `dz` in z-axis, returns `self` (floating interface).
"""
ocs = self.ocs()
self.dxf.center = ocs.from_wcs(Vec3(dx, dy, dz) + ocs.to_wcs(self.dxf.center))
# Avoid Matrix44 instantiation if not required:
if self.is_post_transform_required:
self.post_transform(Matrix44.translate(dx, dy, dz))
return self
def to_ellipse(self, replace=True) -> Ellipse:
"""Convert the CIRCLE/ARC entity to an :class:`~ezdxf.entities.Ellipse` entity.
Adds the new ELLIPSE entity to the entity database and to the same layout as
the source entity.
Args:
replace: replace (delete) source entity by ELLIPSE entity if ``True``
"""
from ezdxf.entities import Ellipse
layout = self.get_layout()
if layout is None:
raise DXFValueError("valid layout required")
ellipse = Ellipse.from_arc(self)
if replace:
replace_entity(self, ellipse, layout)
else:
add_entity(ellipse, layout)
return ellipse
def to_spline(self, replace=True) -> Spline:
"""Convert the CIRCLE/ARC entity to a :class:`~ezdxf.entities.Spline` entity.
Adds the new SPLINE entity to the entity database and to the same layout as the
source entity.
Args:
replace: replace (delete) source entity by SPLINE entity if ``True``
"""
from ezdxf.entities import Spline
layout = self.get_layout()
if layout is None:
raise DXFValueError("valid layout required")
spline = Spline.from_arc(self)
if replace:
replace_entity(self, spline, layout)
else:
add_entity(spline, layout)
return spline