Programmers may define a line set as an array of polylines to accelerate hit-testing, pathfinding
https://magic-wiki.win/index.php/How_to_Measure_for_the_Correct_AC_Line_Set_Size
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.