Intersections

Example: See CollisionExample in the examples repository for cross-shape intersection tests in action.

If you want to check for collisions between two shapes, intersections might be a good choice for your calculations.

2D Intersections

The Intersection2D class has nifty static methods for doing just that:

bool isGrounded = Intersection2D.RectangleOnRectangle(playerRectangle, groundRectangle);
bool inRange = Intersection2D.CircleOnCircle(positionA, radiusA, positionB, radiusB);
bool clicked = Intersection2D.PointInRectangle(mousePosition, buttonRectangle);

The full list of 2D intersection tests includes: - PointInCircle / PointInCircleSquared - CircleOnCircle / CircleOnCircleSquared - CircleInCircle / CircleInCircleSquared - PointInRectangle - RectangleOnRectangle - CircleOnRectangle - PointOnLine - CircleOnLine - LineOnLine - LineOnRectangle

The "Squared" variants skip the square root calculation and are faster when you only need a boolean result.

3D Intersections

Intersection3D provides ray-based collision tests:

RayCollision collision = Intersection3D.RayInSphereCollision(ray, spherePosition, sphereRadius);
if (collision.DidHit)
{
    Vector3 hitPoint = collision.Point;
    float distance = collision.Distance;
}

There's also a simpler boolean check:

bool hit = Intersection3D.RayInSphere(ray, spherePosition, sphereRadius);

Interfaces

Clockwork provides interfaces such as IIntersectsWithRectangle, IIntersectsWithCircle, IIntersectsWithLine, IIntersectsWithPoint, and IIntersectsWithRay which can be implemented in classes to create a collision system between objects. Clockwork already has a few cases of this with shapes:

LineShape laser = new(3, Colors.Red);
RectangleShape enemy = new(10, 10, Colors.Orange);
bool doesHit = enemy.IntersectsWithLine(laser.StartPosition, laser.EndPosition);