Ray2.cs

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namespace Engine {
    public struct Ray2 : IEquatable<Ray2> {
        public Vector2 Position;
 
        public Vector2 Direction;
 
        public Ray2(Vector2 position, Vector2 direction) {
            Position = position;
            Direction = direction;
        }
 
        public override bool Equals(object obj) => obj is Ray2 && Equals((Ray2)obj);
 
        public override int GetHashCode() => Position.GetHashCode() + Direction.GetHashCode();
 
        public override string ToString() => $"{Position.ToString()},{Direction.ToString()}";
 
        public bool Equals(Ray2 other) => Position == other.Position && Direction == other.Direction;
 
        public float? Intersection(BoundingRectangle rectangle) {
            float num = 0f;
            if (Direction.X == 0f) {
                if (Position.X < rectangle.Min.X
                    || Position.X > rectangle.Max.X) {
                    return null;
                }
            }
            else {
                float num2 = 1f / Direction.X;
                float num3 = (rectangle.Min.X - Position.X) * num2;
                float num4 = (rectangle.Max.X - Position.X) * num2;
                if (num3 > num4) {
                    float num5 = num3;
                    num3 = num4;
                    num4 = num5;
                }
                num = MathUtils.Max(num3, num);
                if (num > num4) {
                    return null;
                }
            }
            if (Direction.Y == 0f) {
                if (Position.Y < rectangle.Min.Y
                    || Position.Y > rectangle.Max.Y) {
                    return null;
                }
            }
            else {
                float num6 = 1f / Direction.Y;
                float num7 = (rectangle.Min.Y - Position.Y) * num6;
                float num8 = (rectangle.Max.Y - Position.Y) * num6;
                if (num7 > num8) {
                    float num9 = num7;
                    num7 = num8;
                    num8 = num9;
                }
                num = MathUtils.Max(num7, num);
                if (num > num8) {
                    return null;
                }
            }
            return num;
        }
 
        public float? Intersection(BoundingCircle circle) {
            Vector2 v = circle.Center - Position;
            float num = v.LengthSquared();
            float num2 = circle.Radius * circle.Radius;
            if (num < num2) {
                return 0f;
            }
            float num3 = Vector2.Dot(Direction, v);
            if (num3 < 0f) {
                return null;
            }
            float num4 = num2 + num3 * num3 - num;
            if (!(num4 < 0f)) {
                return num3 - MathF.Sqrt(num4);
            }
            return null;
        }
 
        public Vector2 Sample(float distance) => Position + Direction * distance;
 
        public static Ray2 Transform(Ray2 r, Matrix m) {
            Transform(ref r, ref m, out Ray2 result);
            return result;
        }
 
        public static void Transform(ref Ray2 r, ref Matrix m, out Ray2 result) {
            Vector2.Transform(ref r.Position, ref m, out result.Position);
            Vector2.TransformNormal(ref r.Direction, ref m, out result.Direction);
        }
 
        public static bool operator ==(Ray2 a, Ray2 b) => a.Equals(b);
 
        public static bool operator !=(Ray2 a, Ray2 b) => !a.Equals(b);
    }
}