# Optimal Any-Angle Pathfinding In Practice

@article{Harabor2016OptimalAP, title={Optimal Any-Angle Pathfinding In Practice}, author={Daniel Damir Harabor and Alban Grastien and Dindar {\"O}z and Vural Aksakalli}, journal={J. Artif. Intell. Res.}, year={2016}, volume={56}, pages={89-118} }

Any-angle pathfinding is a fundamental problem in robotics and computer games. [... ] Key Result In a range of empirical comparisons we show that Anya is competitive with several recent (sub-optimal) online and pre-processing based techniques and is up to an order of magnitude faster than the most common benchmark algorithm, a grid-based implementation of A. Expand

## Figures and Tables from this paper

## 31 Citations

### Fast and Almost Optimal Any-Angle Pathfinding Using the 2k Neighborhoods

- Computer ScienceSOCS
- 2017

It is shown that a well-known pre-processing technique, namely subgoal graphs, originally proposed for (non anyangle) 8-connected grids, can be straightforwardly adapted to the 2 neighborhoods, a family of neighborhoods that allow an increasing number of movements as k is increased, which yields a pathfinder that computes 2-optimal paths very quickly.

### CWave: High-performance single-source any-angle path planning on a grid

- Computer Science2017 IEEE International Conference on Robotics and Automation (ICRA)
- 2017

The key idea of the presented algorithm is that it does not represent the grid as a graph and uses discrete geometric primitives to define the wave front and the performance of the algorithm on three maps is demonstrated to be significantly faster than that of Theta∗, Lazy Theta ∗ and Field A∗ adapted for single-source planning.

### Optimal Any-Angle Pathfinding on a Sphere

- Computer ScienceJ. Artif. Intell. Res.
- 2021

An any-angle pathfinding algorithm for calculating the shortest path between point pairs over the surface of a sphere that preserves all primary benefits of Anya in Euclidean geometry and always returns an optimal path on a sphere and does so entirely on-line, without any preprocessing or large memory overheads.

### CWave: Theory and Practice of a Fast Single-source Any-angle Path Planning Algorithm

- Computer ScienceRobotica
- 2019

The paper discusses foundations and experimental validation of CWave, and presents future work to address the limitations of the current implementations and obtain further performance enhancements.

### Towards Time-Optimal Any-Angle Path Planning With Dynamic Obstacles

- Computer ScienceICAPS
- 2021

This work presents two algorithms, grounded in the same idea, that can obtain provably optimal solutions to the considered problem and conducts a thorough empirical evaluation showing that the latter algorithm might be as fast as the previously-known greedy non-optimal solver while providing solutions of better quality.

### A Suboptimality Bound for 2k Grid Path Planning

- Mathematics, Computer ScienceSOCS
- 2018

A suboptimality bound is derived, as a function of k, that generalizes previously known bounds for the 4and 8connected grids and strongly suggests that vertices need to be placed in corners in order to obtain near-optimal solutions.

### Grid Pathfinding on the 2 k Neighborhoods

- Computer ScienceAAAI 2017
- 2017

Three contributions that enable the construction of effective grid path planners for extended 2 k -neighborhoods are described that are competitive with the "any-angle" path planner Theta$^*$ both in terms of solution quality and runtime.

### Any Angle Path Finding in Stochastic Obstacle Scenes

- Computer ScienceICAAI 2019
- 2019

This work presents Any-Angle (ANYA) path finding in discretized stochastic obstacle scenes using the exact algorithm AO* with caching (CAO*), which is already shown to outperform shortest path algorithms by investigating the interval sets.

### Any-Angle Pathfinding for Multiple Agents Based on SIPP Algorithm

- Computer ScienceICAPS
- 2017

A novel any-angle planner based on Safe Interval Path Planning (SIPP) algorithm is proposed to find trajectories for an agent moving amidst dynamic obstacles (other agents) on a grid and is used as part of a prioritized multi-agent planner AA-SIPP(m).

### Euclidean Pathfinding with Compressed Path Databases

- Computer ScienceIJCAI
- 2020

This work considers optimal and anytime algorithms for the Euclidean Shortest Path Problem (ESPP) in two dimensions and shows that the auxiliary data structures required by the new method are cheap to build and store and faster than a range of recent ESPP planners.

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