Trait rstar::Point

source · [−]
pub trait Point: Copy + Clone + PartialEq + Debug {
    type Scalar: RTreeNum;

    const DIMENSIONS: usize;

    fn generate(generator: impl FnMut(usize) -> Self::Scalar) -> Self;
    fn nth(&self, index: usize) -> Self::Scalar;
    fn nth_mut(&mut self, index: usize) -> &mut Self::Scalar;
}
Expand description

Defines a point type that is compatible with rstar.

This trait should be used for interoperability with other point types, not to define custom objects that can be inserted into r-trees. Use crate::RTreeObject or crate::primitives::GeomWithData instead. This trait defines points, not points with metadata.

Point is implemented out of the box for arrays like [f32; 2] or [f64; 7] (up to dimension 9) and for tuples like (int, int) and (f64, f64, f64) so tuples with only elements of the same type (up to dimension 9).

Implementation example

Supporting a custom point type might look like this:

use rstar::Point;

#[derive(Copy, Clone, PartialEq, Debug)]
struct IntegerPoint
{
    x: i32,
    y: i32
}

impl Point for IntegerPoint
{
  type Scalar = i32;
  const DIMENSIONS: usize = 2;

  fn generate(mut generator: impl FnMut(usize) -> Self::Scalar) -> Self
  {
    IntegerPoint {
      x: generator(0),
      y: generator(1)
    }
  }

  fn nth(&self, index: usize) -> Self::Scalar
  {
    match index {
      0 => self.x,
      1 => self.y,
      _ => unreachable!()
    }
  }

  fn nth_mut(&mut self, index: usize) -> &mut Self::Scalar
  {
    match index {
      0 => &mut self.x,
      1 => &mut self.y,
      _ => unreachable!()
    }
  }
}

Associated Types

The number type used by this point type.

Associated Constants

The number of dimensions of this point type.

Required methods

Creates a new point value with given values for each dimension.

The value that each dimension should be initialized with is given by the parameter generator. Calling generator(n) returns the value of dimension n, n will be in the range 0 .. Self::DIMENSIONS, and will be called with values of n in ascending order.

Returns a single coordinate of this point.

Returns the coordinate indicated by index. index is always smaller than Self::DIMENSIONS.

Mutable variant of nth.

Implementations on Foreign Types

Implementors