Ejemplo n.º 1
0
        /// <summary>
        ///   Checks whether the specified line segment intersects the passed one.
        /// </summary>
        /// <remarks>
        ///   See http://www.wyrmtale.com/blog/2013/115/2d-line-intersection-in-c for details.
        /// </remarks>
        /// <param name="first">Line segment to check.</param>
        /// <param name="second">Line segment to check.</param>
        /// <param name="intersectionPoint">Intersection point, if found.</param>
        /// <returns>
        ///   <c>true</c>, if both line segments intersect each other, and <c>false</c> otherwise.
        /// </returns>
        public static bool Intersects(this LineSegment2F first, LineSegment2F second, out Vector2F intersectionPoint)
        {
            // Get A,B,C of first line - points ps1 to pe1.
            var a1 = first.Q.Y - first.P.Y;
            var b1 = first.P.X - first.Q.X;
            var c1 = a1 * first.P.X + b1 * first.P.Y;

            // Get A,B,C of second line - points ps2 to pe2.
            var a2 = second.Q.Y - second.P.Y;
            var b2 = second.P.X - second.Q.X;
            var c2 = a2 * second.P.X + b2 * second.P.Y;

            // Get delta and check if the lines are parallel.
            var delta = a1 * b2 - a2 * b1;

            if (Math.Abs(delta) < float.Epsilon)
            {
                intersectionPoint = Vector2F.Zero;
                return false;
            }

            // Return intersection point.
            intersectionPoint = new Vector2F((b2 * c1 - b1 * c2) / delta, (a1 * c2 - a2 * c1) / delta);
            return first.Contains(intersectionPoint) && second.Contains(intersectionPoint);
        }
Ejemplo n.º 2
0
        /// <summary>
        ///   Checks whether the specified line segment intersects the passed one.
        /// </summary>
        /// <remarks>
        ///   See http://jeffe.cs.illinois.edu/teaching/373/notes/x06-sweepline.pdf for details.
        /// </remarks>
        /// <param name="first">Line segment to check.</param>
        /// <param name="second">Line segment to check.</param>
        /// <returns>
        ///   <c>true</c>, if both line segments intersect each other, and <c>false</c> otherwise.
        /// </returns>
        public static bool Intersects(this LineSegment2F first, LineSegment2F second)
        {
            // By definition, line segments that share a point can't intersect.
            if (first.P == second.P || first.P == second.Q || first.Q == second.P || first.Q == second.Q)
            {
                return false;
            }

            var a = first.P;
            var b = first.Q;
            var c = second.P;
            var d = second.Q;

            if (Vector2F.CounterClockwise(a, c, d) == Vector2F.CounterClockwise(b, c, d))
            {
                return false;
            }

            if (Vector2F.CounterClockwise(a, b, c) == Vector2F.CounterClockwise(a, b, d))
            {
                return false;
            }

            return true;
        }
Ejemplo n.º 3
0
        public void TestPolygonDoesNotContainIntersectingLineSegment()
        {
            // ARRANGE.
            var line = new LineSegment2F(new Vector2F(2, 3), new Vector2F(6, 3));

            // ASSERT.
            Assert.IsFalse(this.polygon.Contains(line));
        }
Ejemplo n.º 4
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        public void TestPolygonContainsLineSegment()
        {
            // ARRANGE.
            var line = new LineSegment2F(new Vector2F(2, 3), new Vector2F(4, 3));

            // ASSERT.
            Assert.IsTrue(this.polygon.Contains(line));
        }
Ejemplo n.º 5
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        public void GetLength()
        {
            var s = new LineSegment2F
            {
                Point1 = new Vector2F(1, 2),
                Point2 = new Vector2F(-1, 9),
            };

            Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length, s.GetLength(0, 1, 100, Numeric.EpsilonF)));
            Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length * 0.3f, s.GetLength(0.6f, 0.3f, 100, Numeric.EpsilonF)));
            Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length * 0.3f, s.GetLength(0.1f, 0.4f, 100, Numeric.EpsilonF)));
        }
Ejemplo n.º 6
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        public void GetTangent()
        {
            var s = new LineSegment2F
            {
                Point1 = new Vector2F(1, 2),
                Point2 = new Vector2F(-1, 9),
            };

            Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point2 - s.Point1, s.GetTangent(0)));
            Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point2 - s.Point1, s.GetTangent(0.3f)));
            Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point2 - s.Point1, s.GetTangent(1)));
        }
Ejemplo n.º 7
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        public void Test()
        {
            var s = new LineSegment2F
              {
            Point1 = new Vector2F(1, 2),
            Point2 = new Vector2F(-1, 9),
              };

              Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point1, s.GetPoint(0)));
              Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point2, s.GetPoint(1)));
              Assert.IsTrue(Vector2F.AreNumericallyEqual(s.Point1 * 0.7f + s.Point2 * 0.3f, s.GetPoint(0.3f)));
        }
Ejemplo n.º 8
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        public void GetLength()
        {
            var s = new LineSegment2F
              {
            Point1 = new Vector2F(1, 2),
            Point2 = new Vector2F(-1, 9),
              };

              Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length, s.GetLength(0, 1, 100, Numeric.EpsilonF)));
              Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length * 0.3f, s.GetLength(0.6f, 0.3f, 100, Numeric.EpsilonF)));
              Assert.IsTrue(Numeric.AreEqual((s.Point2 - s.Point1).Length * 0.3f, s.GetLength(0.1f, 0.4f, 100, Numeric.EpsilonF)));
        }
Ejemplo n.º 9
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 public void Flatten()
 {
     var s = new LineSegment2F
       {
     Point1 = new Vector2F(1, 2),
     Point2 = new Vector2F(-1, 9),
       };
       var points = new List<Vector2F>();
       s.Flatten(points, 1, 1);
       Assert.AreEqual(2, points.Count);
       Assert.IsTrue(points.Contains(s.Point1));
       Assert.IsTrue(points.Contains(s.Point2));
 }
Ejemplo n.º 10
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        public void Flatten()
        {
            var s = new LineSegment2F
            {
                Point1 = new Vector2F(1, 2),
                Point2 = new Vector2F(-1, 9),
            };
            var points = new List <Vector2F>();

            s.Flatten(points, 1, 1);
            Assert.AreEqual(2, points.Count);
            Assert.IsTrue(points.Contains(s.Point1));
            Assert.IsTrue(points.Contains(s.Point2));
        }
Ejemplo n.º 11
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        public void TestLineIntersectsCircle()
        {
            // ARRANGE.
            var line   = new LineSegment2F(new Vector2F(-2.0f, 0.0f), new Vector2F(2.0f, 0.0f));
            var circle = CircleF.UnitCircle;

            Vector2F?first;
            Vector2F?second;

            // ACT.
            var intersects = line.Intersects(circle, out first, out second);

            // ASSERT.
            Assert.IsTrue(intersects);
            Assert.IsNotNull(first);
            Assert.IsNotNull(second);
            Assert.AreEqual(new Vector2F(1.0f, 0.0f), first);
            Assert.AreEqual(new Vector2F(-1.0f, 0.0f), second);
        }
Ejemplo n.º 12
0
        public void TestLineIntersectsCircle()
        {
            // ARRANGE.
            var line = new LineSegment2F(new Vector2F(-2.0f, 0.0f), new Vector2F(2.0f, 0.0f));
            var circle = CircleF.UnitCircle;

            Vector2F? first;
            Vector2F? second;

            // ACT.
            var intersects = line.Intersects(circle, out first, out second);

            // ASSERT.
            Assert.IsTrue(intersects);
            Assert.IsNotNull(first);
            Assert.IsNotNull(second);
            Assert.AreEqual(new Vector2F(1.0f, 0.0f), first);
            Assert.AreEqual(new Vector2F(-1.0f, 0.0f), second);
        }
Ejemplo n.º 13
0
        /// <summary>
        ///   Checks whether the specified rectangle intersects the passed circle.
        /// </summary>
        /// <param name="rectangle">
        ///   Rectangle to check.
        /// </param>
        /// <param name="circle">
        ///   Circle to check.
        /// </param>
        /// <returns>
        ///   <c>true</c>, if rectangle and circle intersect each other, and <c>false</c> otherwise.
        /// </returns>
        public static bool Intersects(this RectangleF rectangle, CircleF circle)
        {
            // Check if rectangle contains center.
            if (rectangle.Contains(circle.Center))
            {
                return true;
            }

            // Check each edge.
            var topLeft = new Vector2F(rectangle.X, rectangle.Y);
            var bottomLeft = new Vector2F(rectangle.X, rectangle.MaxY);
            var topRight = new Vector2F(rectangle.MaxX, rectangle.Y);
            var bottomRight = new Vector2F(rectangle.MaxX, rectangle.MaxY);

            var left = new LineSegment2F(topLeft, bottomLeft);
            var right = new LineSegment2F(topRight, bottomRight);
            var top = new LineSegment2F(topLeft, topRight);
            var bottom = new LineSegment2F(bottomLeft, bottomRight);

            return left.Intersects(circle) || right.Intersects(circle) || top.Intersects(circle)
                   || bottom.Intersects(circle);
        }
Ejemplo n.º 14
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        public void TestPolygonDoesNotContainOutsideLineSegment()
        {
            // ARRANGE.
            var line = new LineSegment2F(new Vector2F(2, 7), new Vector2F(4, 7));

            // ASSERT.
            Assert.IsFalse(this.polygon.Contains(line));
        }