Curves and Profiles
===================

Parametric curves in 3D, with planar curves as a special case, and the frames that carry a profile
along them. Points can be passed as tuples, lists, ``Vec3``, ``Vec2``, ``Point2`` or NumPy arrays;
batched results come back as NumPy arrays. Curves never change after construction, so one curve can
be shared by many nodes.

.. currentmodule:: pyvcad

Curves
------

.. autoclass:: Curve
   :members:
   :undoc-members:

.. autoclass:: CurveHit
   :members:
   :undoc-members:

.. autoclass:: LineSegment
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: PolylineCurve
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: ArcCurve
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: BezierCurve
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: BSplineCurve
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: CompositeCurve
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: TrimmedCurve
   :members:
   :undoc-members:
   :special-members: __init__

Frames
------

.. autoclass:: CurveFrames
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: CurveFrame
   :members:
   :undoc-members:

Profiles
--------

.. autoclass:: Profile
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: ProfileHit
   :members:
   :undoc-members:

Sketches
--------

Draw profiles and paths step by step with a pen, place them on any plane, and build them from
construction geometry. The guide :doc:`../../guides/modeling/sketching` walks through all of these.

.. autoclass:: Sketch
   :members:
   :undoc-members:
   :special-members: __init__

.. autoclass:: Plane
   :members:
   :undoc-members:
   :special-members: __init__

Construction geometry
---------------------

Closed-form intersections, tangents and corner treatments. Lines are infinite lines through two
points and circles are a centre and a radius; every function returns all of its solutions, in a
stated order, as NumPy arrays.

.. autofunction:: intersect_lines
.. autofunction:: intersect_line_circle
.. autofunction:: intersect_circles
.. autofunction:: tangent_points
.. autofunction:: tangent_lines
.. autofunction:: fillet_curves
.. autofunction:: chamfer_curves

Curves from data
----------------

Mesh paths (``MeshPath.to_curve()``), mesh and selection borders (``SurfaceMesh.boundary_loops()``,
``MeshSelection.boundary_loops()``) and node contours all return ordinary curves.
``Profile.cross_section()`` gives the region of a slice instead of its outlines.

.. autofunction:: contour_curves