/// <summary>
/// Finds all intersections of given analytic objects. They must not
/// contain <see cref="Point"/>s and duplicate objects.
/// </summary>
/// <param name="objects">The objects to be intersected.</param>
/// <returns>The intersections array.</returns>
public static Point[] Intersect(params IAnalyticObject[] objects)
{
// Find which of the passed objects are lines and circles
var lines = objects.OfType <Line>().ToArray();
var circles = objects.OfType <Circle>().ToArray();
// Prepare an array of possible intersections
Point[] intersections;
// Prepare an array or intersected objects
IAnalyticObject[] intersected;
// First check if we have two lines...
if (lines.Length >= 2)
{
// If yes, then we intersect them
var intersection = lines[0].IntersectionWith(lines[1]);
// If there is no intersection, then we can immediately return an empty array
if (intersection == null)
{
return(Array.Empty <Point>());
}
// Otherwise we set the intersections to this single one
intersections = new[] { intersection.Value };
// And set the intersected objects
intersected = new IAnalyticObject[] { lines[0], lines[1] };
}
// If we don't have two lines, check if we have at best one line
else if (lines.Length == 1)
{
// If yes, we'll intersect this line with a circle (there must be at least one)
intersections = circles[0].IntersectWith(lines[0]);
// And set the intersected objects
intersected = new IAnalyticObject[] { lines[0], circles[0] };
}
// If we don't have any line...
else
{
// We intersect the first two circles
intersections = circles[0].IntersectWith(circles[1]);
// And set the intersected objects
intersected = new IAnalyticObject[] { circles[0], circles[1] };
}
// Now we find the remaining (non-intersected) objects
var remaningObjects = objects.Where(analyticObject => !intersected.Contains(analyticObject)).ToArray();
// And select those intersection points that lie on all the remaining objects
return(intersections.Where(point => remaningObjects.All(analyticObject => LiesOn(analyticObject, point))).ToArray());
}
/// <summary>
/// Checks if a given point lies on a given analytic object. The object must not be a point.
/// </summary>
/// <param name="analyticObject">The analytic object.</param>
/// <param name="point">The point.</param>
/// <returns>true, if the point lies on the object; false otherwise.</returns>
public static bool LiesOn(IAnalyticObject analyticObject, Point point) =>
// Switch based on the analytic object
analyticObject switch
{
