guest@BipbopPC:~/projects$ cat openmp-astar.md

An interactive C++/SFML tool that visualizes A* search in real time. The user places the start and target nodes, draws walls, and watches the search expand across the grid.

The sequential version kept its open set, closed set, and target pointers in shared state, so parallelizing it as-is was never going to work. Refactoring all of that into a self-contained AStarSolver struct made the problem embarrassingly parallel, with no loop-carried dependencies at all, and after that a single #pragma omp parallel for ran 1,000 independent searches for a 2.64x speedup at 3 threads (88% efficiency). Past 3 threads the memory bus becomes the bottleneck, since every solver carries its own copy of the grid.