Geometric computational complexity

What is computational complexity in math?
Computational complexity theory is a mathematical research area in which the goal is to quantify the resources required to solve computational problems.
It is concerned with algorithms, which are computational methods for solving problems..
A method for solving a wide range of geometric problems, including computing the intersection of two lines or planes and triangulating a polygon.
The algorithm works by sweeping a line or plane across the geometry and updating a data structure as it goes._{Oct 1, 2023}

What is computational complexity in math?