How can you determine the distance between two points on a display screen?

To determine the distance between two points on a screen, given their coordinates (x1, y1) and (x2, y2), the Euclidean distance formula is used:

[ \text{distance} = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} ]

Example in C++:

#include <cmath>
#include <iostream>

struct Point {
    int x;
    int y;
};

double distance(const Point& p1, const Point& p2) {
    int dx = p2.x - p1.x;
    int dy = p2.y - p1.y;
    return std::sqrt(dx * dx + dy * dy);
}

int main() {
    Point a{10, 20};
    Point b{30, 40};
    std::cout << "Distance: " << distance(a, b) << std::endl;
    return 0;
}

This distance is in pixels or units of screen coordinates.