cell-map: many-layer 2D cellular maps

This crate provides the CellMap type, a 2D map with many layers comprised of cells that can store arbitrary data. It is based on ANYbotics/grid_map, a C++ ROS package which provides the same type of data structre.

CellMap uses ndarray::Array2 to store its data in an efficient and scalable format. It also uses nalgebra types for expressing vectors and points.

Getting Started

Layers

Each layer of the cell map is represented by its own ndarray::Array2 array. The map indexes each layer by an enum implementing the Layer trait. A derive macro is provided to simplify this, for example:

```rust use cell_map::Layer;

[derive(Layer, Clone, Debug)]

enum MyLayer { Height, Gradient, Roughness } ```

The Layer trait is required to be Clone, and is recommended to be Debug.

Creating a CellMap

To create a new map:

```rust use cell_map::{CellMap, CellMapParams};

// Creates a new 5x5 map where each cell is 1.0 units wide, which is centred on (0, 0). let mymap = CellMap::::new( CellMapParams { cellsize: Vector2::new(1.0, 1.0), num_cells: Vector2::new(5, 5), centre: Vector2::new(0.0, 0.0), }, 1.0, ); ```

Iterating Over Cells

CellMap provides the following iteration types over its cells: - CellIter - iterate each cell in the map - WindowIter - iterate a window through the map

All iterators also provide a mutable variant, and more iterators are planned in the future!

You can modify iterators so they produce Layered or Indexed iterators as well.

```rust // Check all the cells in our map are 1, this will be true assereq!(mymap.iter().all(|v| v == 1.0))

// Use a window iterator to change all cells not on the border of the map to 2 map.windowitermut(Vector2::new(1, 1)).for_each(|mut v| { v[(1, 1)] = 2.0; });

// Overwrite all values on the Roughness layer to be zero map.itermut().layer(MyLayer::Roughness).foreach(|v| *v = 0.0);

// Check that our map is how we expect it for ((layer, cell), value) in map.iter().indexed() { if let MyLayer::Roughness = layer { asserteq!(value, 0.0); } else if cell.x == 0 || cell.x == 4 || cell.y == 0 || cell.y == 4 { asserteq!(value, 1.0); } else { assert_eq!(value, 2.0); } } ```