# jps 1.1.1

Jump Point Search Implementation for Path Finding.
Documentation

# jps : Jump Point Search in Rust.

Jump Point Search Algorithm Implementation in Rust.

# Current implementation status

## JPS Implementation

• 3D case✅

Currently no lifetime notation is used, and hence a few unnecessary copies have to be performed. Lifetime is needed to be considered for improving the speed/efficiency.

# Usage

[dependencies]
jps = "1.1"

Two steps to use JPS:

1. create a GraphSearch using either new_v1 or new_v2
2. call plan to plan a path from start to goal.
/* using HashMap as the map input.
`fmap` can be `None` such that a grid will be regarded as free as long as it is not occupied and is within the legal boxed-boundary. */
GraphSearch::new_v1(
fmap_: Option<HashSet<(i32, i32, i32)>>,
omap_: HashSet<(i32, i32, i32)>,
xdim: [i32; 2],
ydim: [i32; 2],
zdim: [i32; 2],
eps_: f32,
)-> Self

/* using a binary map as the map input */
GraphSearch::new_v2(
map: &[bool],
xdim: [i32; 2],
ydim: [i32; 2],
zdim: [i32; 2],
eps_: f32,
// goal: (i32, i32, i32),
// use_jps_: bool,
) -> Self

/* path-finding */
plan(
&mut self,
start: (i32, i32, i32),
goal: (i32, i32, i32),
usejps: bool,
max_expand: i32,
) -> bool

# Example & Test

cargo test -- --show-output

the output shows:

path is :
(0, 0, 0) ➡ (0, 1, 0)➡ (0, 2, 0)➡ (0, 3, 0)➡ (1, 4, 1)➡ (2, 4, 1)➡ (3, 4, 1)➡ (4, 3, 2)➡ (4, 2, 2)➡ (4, 1, 2)➡ (3, 0, 3)➡ (2, 1, 4)➡ (2, 2, 4)➡ (3, 3, 4)➡ (4, 4, 4)
turnings are :
(0, 0, 0) (0, 3, 0) (1, 4, 1) (3, 4, 1) (4, 3, 2) (4, 1, 2) (3, 0, 3) (2, 1, 4) (2, 2, 4) (4, 4, 4)

# Release Note

## Ver 1.1.1

• API changed.

xdim : i32 is replaced by xbound: [i32;2]. xbound[0] ≤ x < xbound[1] defines the x-axis grid searching space. (similar case for ydim and zdim)

• Add a functional feature, namely decomp, for finding ellipsoid and decomposition.

To use this feature, in Cargo.toml add

[dependencies]
jps = { version = "1.1", features = ["decomp"] }

You need to implement trait Voxelable for voxelization and devoxelization.

Then you can init a Decomp, and decompose it to perform the decomposition.

As a simple example, check the example in the test, or type:

cargo test --release --features=decomp -- --show-output

# Reference

Logic follows the C++ version (https://github.com/KumarRobotics/jps3d)

Also NOTE that some functions havn't been thoroughly tested, so please let me know if there is any error.