Programmers may define a line set as an array of polylines to accelerate hit-testing, pathfinding

https://romeo-wiki.win/index.php/Copper_Line_Set_Sizing_Mistakes_That_Can_Hurt_Performance

Programmers may define a line set as an array of polylines to accelerate hit-testing, pathfinding, and collision detection, using spatial indices to swiftly query segments in large interactive scenes.