archery

Type Members

1. case class Box(x: Float, y: Float, x2: Float, y2: Float) extends Geom with Product with Serializable

   

2. case class Branch[A](children: Vector[Node[A]], box: Box) extends Node[A] with Product with Serializable

   

3. case class Entry[A](geom: Geom, value: A) extends HasGeom with Product with Serializable

   

   Represents a point with a value.

   Represents a point with a value.

   We frequently use value.== so it's important that A have a reasonable equality definition. Otherwise things like remove and contains may not work very well.

4. sealed trait Geom extends AnyRef

   

   Geometry represents a box (or point).

   Geometry represents a box (or point).

   (x1, y1) is the lower left point and (x2, y2) is upper right.

   So Box(1, 2, 5, 4) is at (1, 2) and is 4 wide and 2 high. Points have no width or height, so x2/y2 are equal to x/y.

5. sealed abstract class HasGeom extends AnyRef

   

   Abstract data type that has a geom element.

   Abstract data type that has a geom element.

   This generalizes Node[A] (the nodes of the tree) and Entry[A] (the values being put in the tree). It functions like a structural type (but isn't one, because structural types are slow).

6. sealed trait Joined[A] extends Iterable[A]

   

   This is a small ADT that we use to avoid building too many intermediate vectors.

   This is a small ADT that we use to avoid building too many intermediate vectors.

   It allows us to concatenate a whole bunch of vectors or single elements cheaply, and then iterate over them later.

7. case class Leaf[A](children: Vector[Entry[A]], box: Box) extends Node[A] with Product with Serializable

   

8. sealed abstract class Node[A] extends HasGeom

   

   Abstract data type for nodes of the tree.

   Abstract data type for nodes of the tree.

   There are two types of Node: Branch and Leaf. Confusingly, leaves don't actaully hold values, but rather a leaf contains a sequence of entries. This design is commmon to RTree implementations and it seemed like a good idea to keep the nomenclature the same.

9. case class Point(x: Float, y: Float) extends Geom with Product with Serializable

   

10. case class RTree[A](root: Node[A], size: Int) extends Product with Serializable

    

    This is the magnificent RTree, which makes searching ad-hoc geographic data fast and fun.

    This is the magnificent RTree, which makes searching ad-hoc geographic data fast and fun.

    The RTree wraps a node called 'root' that is the actual root of the tree structure. RTree also keeps track of the total size of the tree (something that individual nodes don't do).