http://en.wikipedia.org/wiki/Chan%27s_algorithm

http://www.ruby-doc.org/stdlib-1.9.3/libdoc/delegate/rdoc/Object.html

Like a TwoPointLine, but not implicitly of infinite length

http://gvu.gatech.edu/people/official/jarek/graphics/papers/04PolygonBooleansMargalit.pdf

Union is already implemented. Do the others at some point.

Returns a Vector that's perpendicular to the Edge

A Circle or RegularPolygon with a nil center should be equal to another class of the same type with the same radius or diameter (and number of sides, for RegularPolygon)

Rectangle[...] seems wrong now that I look at it again. Switch to the more standard Rectangle.new syntax.

Rectangle.new [-1,-1],[1,1] should == Rectangle.new Size[2,2]

Currently #== is aliased to #eql?

The current version is a skeleton that was rushed in support of the engineering gem.

Like Polygon#outset, but for Rectangle

Needs accessors, etc

• parallel? line - true if the passed line is parallel
• intersect? line - true if the passed line intersects
• angle - the angle between the two lines
• direction - a vector pointing along the line
• equal? line - true if collinear
• distance
  • point - distance to the point
  • line - closest distance between the lines
  • circle - distance to the circle's center minus its radius

• pentagon - returns a regular pentagon
• hexagon - returns a regular hexagon
• regular_polygon - constructs a regular polygon with a specified number of edges

min returns a Point that's on the Rectangle and closest to the origin
max returns a Point that's on the Rectangle and farthest from the origin
minmax returns the Array of Points [min, max]

Methods

• inside?
  • checks if a passed point is inside, or on the boundary
  • checks if a passed edge is entirely inside, or on the boundary
  • checks if a passed polygon is entirely inside, or matches the boundary entirely
• outside? - opposite of inside?
• intersect?
  • true if passed line intersects the polygon
  • true if any part of the passed polygon is inside?
• equal? polygon - true if passed polygon has same vertices, and number of vertices
• on_boundary?
  • true if passed point is a vertex or on an edge
  • true if passed line is an edge or entirely on an edge
  • true if passed polygon is equal?
• vertex? point - true if passed point is a vertex of the polygon
• edge? line - true if passed line is an edge of the vertex
• edge? point - true if passed point in on any edge
• concave?
• convex?
• decompose - cuts a concave polygon into 1 or more convex polygons
• hull - creates a convex hull
• square - smallest enclosing Square
• rectangle - smallest enclosing Rectangle

Cluster

• RegularPolygon

Like Point, but with a different name

http://gvu.gatech.edu/people/official/jarek/graphics/papers/04PolygonBooleansMargalit.pdf

Subclass of Rectangle?

http://fcacciola.50webs.com/Offseting%20Methods.htm

http://stackoverflow.com/questions/1109536/an-algorithm-for-inflating-deflating-offsetting-buffering-polygons

Straight Skeleton: http://en.wikipedia.org/wiki/Straight_skeleton
http://www.dma.fi.upm.es/mabellanas/tfcs/skeleton/html/documentacion/Straight%20Skeletons%20Implementation.pdf

Special subclasses that are always zero, always compare as zero and are compatible with Points and Sizes of any length.

http://en.wikipedia.org/wiki/Kite_(geometry)

Need to add Point#coerce

Like a Polygon, but not necessarily closed and not limited to straight lines

Accessors

• vertices
• edges

Represents the concept of a rotation regardless of the underlying implementation. Has methods for getting the equivalent rotation matrix and the equivalent quaternion.

Applies spaceship to each corresponding element and returns a new Point with the results

Monkeypatch it into Vector as well?

Two semicircles connected by parallel lines

http://en.wiktionary.org/wiki/obround

Fix test framework for Line class

• Rename file
• Rename test case (not a Point test)
• Add test cases for individual cluster classes

Returns an array of Points

eg. Point[0..1,1] would return [Point[0,1], Point[1,1]]

http://en.wikipedia.org/wiki/Graham_scan
http://branch14.org/snippets/convex_hull_in_ruby.html

Adding two elements should return a Path that's the union of the elements, or an exception if they don't intersect.

A portion of a circle

circle should return a Circle that encloses the RegularPolygon

incircle should return a Circle that incribes the RegularPolygon

Rectangle, Square, Obround, etc should take left, right, top, bottom, bottom_left, top_right, width, height, etc...

http://stackoverflow.com/a/1968345/44747

A sequence of Edges that may, or may not, be closed. It's like a Polygon in that it only contains straight lines, but also like a Path in that it isn't necessarily closed.

Implement north, south, east, and west methods in addition to the existing up, down, left and right methods

Generates a new Rectangle that's inset by the specified amount. Overloads for single inset all around, horizontal/vertical insets, and top/left/bottom/right insets. Negative numbers produce an "outset".

A Polygon that's constrained to be a regular polygon. Has accessors for radius and center.