affiner 0.3.1

New features

• as_ellipse2d() creates an Ellipse2D R6 object representing a 2D ellipse (or vector of ellipses) (#46).

• as_polygon2d() creates a Polygon2D R6 object representing a 2D polygon (#46).

  • isotoxal_2ngon_polygon2d() creates an isotoxal 2n-gon [Polygon2D] object; star_polygon2d() is an alias (#78).
  • rectangle_polygon2d() creates a rectangle [Polygon2D] object (#78).
  • regular_ngon_polygon2d() creates a regular n-gon [Polygon2D] object (#78).

• as_segment2d() creates a Segment2D R6 object representing a vector of 2D line segments (#75).

• dot_product1d(), dot_product2d(), and dot_product3d() are new exported functions that compute the dot (inner) product of two coordinate vectors (#61).
  You may also (continue to) use the * and (if R >= 4.3) the %*% operators to compute the dot (inner) product.

• has_overlap2d() tests whether two 2D objects (ellipses/circles or convex polygons) have a non-zero-area overlap (#46).

• as_coord2d.Coord3D() now supports oblique projections onto arbitrary planes (not just the xy-plane) and gains a roll parameter to rotate the in-plane coordinate frame around the plane normal after the azimuth/inclination alignment.

• intersection() now supports Line2D and Ellipse2D pairs, returning 0, 1, or 2 intersection points.

• is_ellipse2d() tests whether an object is a Ellipse2D R6 class.

• is_segment2d() tests whether an object is a Segment2D R6 class.

• is_polygon2d() tests whether an object is a Polygon2D R6 class.

• painter_depth() computes painter's algorithm depth values for Coord2D, Coord3D, Polygon2D, and Segment2D objects under parallel (orthographic or oblique) projections.

• painter_order() wraps painter_depth() and order() to return the integer indices for painter's algorithm draw order (farthest first) for Coord2D, Coord3D, Segment2D, and Polygon2D objects.

• sort.Coord2D() and sort.Coord3D() sort coordinate/segment vectors by painter's depth (farthest first by default), for use with the painter's algorithm.

Bug fixes and minor improvements

• permute3d() now correctly returns a transform3d object instead of a transform2d object.
• rotate3d() now correctly returns a transform3d object instead of a plain matrix.
• shear3d() now correctly returns a transform3d object instead of a transform2d object.
• rgl::plot3d() method added for Plane3D objects (wraps rgl::planes3d()).