calculate vector collision in csharp

main.cs
public static bool DoLinesIntersect(Vector2 start1, Vector2 end1, Vector2 start2, Vector2 end2)
{
    // calculate the direction of each line
    Vector2 dir1 = end1 - start1;
    Vector2 dir2 = end2 - start2;

    // calculate the cross product of the directions
    float cross = dir1.X * dir2.Y - dir1.Y * dir2.X;

    // if the cross product is zero, the lines are parallel and do not intersect
    if (cross == 0f)
    {
        return false;
    }

    // calculate the difference in position of the two start points
    Vector2 diff = start2 - start1;

    // calculate the parameter values for the lines where they intersect
    float t = (diff.X * dir2.Y - diff.Y * dir2.X) / cross;
    float u = (diff.X * dir1.Y - diff.Y * dir1.X) / cross;

    // if both parameters are within 0 and 1, then the lines intersect
    if (t >= 0f && t <= 1f && u >= 0f && u <= 1f)
    {
        return true;
    }

    return false;
}
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