Represents a vector and duration of the inertial motion, calculated by the InertiaController.
Beispiel #1
0
        /// <summary>
        /// Gets inertial motion parameters: distance and duration.
        /// </summary>
        /// <param name="hostBounds">The host bounds.</param>
        /// <param name="windowBounds">The window bounds.</param>
        /// <returns>
        /// The inertial motion parameters: distance and duration.
        /// </returns>
        public InertialMotion GetInertialMotionParameters(Rect hostBounds, Rect windowBounds)
        {
            if (mouseTrails.Count < 2) return null;

            var mouseTrailsArray = mouseTrails.ToArray();

            Point startPosition = mouseTrailsArray[0].Position;
            DateTime startTime = mouseTrailsArray[0].Timestamp;
            Point endPosition = mouseTrailsArray[mouseTrails.Count - 1].Position;
            DateTime endTime = mouseTrailsArray[mouseTrails.Count - 1].Timestamp;

            double timeBetweenNowAndLastMove = (DateTime.Now - endTime).TotalMilliseconds;
            Vector2 vector = new Vector2(startPosition, endPosition);

            if (timeBetweenNowAndLastMove < DELAY_BEFORE_MOUSE_UP_IN_MILLISECONDS && !vector.IsZero)
            {
                double time = (endTime - startTime).TotalSeconds;
                time = (time == 0) ? 0.001 : time;

                double distance = vector.Length / pixelsPerMeter;

                double intialVelocity = distance / time;

                double expectedDistance = ((intialVelocity * intialVelocity) / (2 * COEFFICIENT_OF_SLIDING_FRICTION * GRAVITATIONAL_ACCELERATION));
                double expectedTime = (2 * expectedDistance) / intialVelocity;

                double shiftX = Math.Round(vector.LengthX * expectedDistance / distance);
                double shiftY = Math.Round(vector.LengthY * expectedDistance / distance);

                // New Inertial Motion Vector
                Vector2 imVector = new Vector2(endPosition, shiftX, shiftY).Round();
                double expectedLength = imVector.Length;

                Rect bounds = hostBounds.Add(-windowBounds.Width, -windowBounds.Height);

                if (bounds.Contains(endPosition))
                {
                    imVector = EnsureEndPointInBounds(imVector, bounds).Round();
                }
                else if (hostBounds.Contains(endPosition))
                {
                    imVector = EnsureEndPointInBounds(imVector, hostBounds).Round();
                }

                // Reduce expected time if the Inertial Motion Vector was truncated by the bounds
                double realTime = (expectedLength == 0) ? 0 : (expectedTime * imVector.Length / expectedLength);

                var motion = new InertialMotion()
                {
                    Seconds = realTime,
                    EndPosition = imVector.End,
                    EasingFunction = new CubicEase()
                    {
                        EasingMode = EasingMode.EaseOut
                    }
                };

                return motion;
            }

            return null;
        }
        /// <summary>
        /// Gets inertial motion parameters: distance and duration.
        /// </summary>
        /// <param name="hostBounds">The host bounds.</param>
        /// <param name="windowBounds">The window bounds.</param>
        /// <returns>
        /// The inertial motion parameters: distance and duration.
        /// </returns>
        public InertialMotion GetInertialMotionParameters(Rect hostBounds, Rect windowBounds)
        {
            if (mouseTrails.Count < 2)
            {
                return(null);
            }

            var mouseTrailsArray = mouseTrails.ToArray();

            Point    startPosition = mouseTrailsArray[0].Position;
            DateTime startTime     = mouseTrailsArray[0].Timestamp;
            Point    endPosition   = mouseTrailsArray[mouseTrails.Count - 1].Position;
            DateTime endTime       = mouseTrailsArray[mouseTrails.Count - 1].Timestamp;

            double  timeBetweenNowAndLastMove = (DateTime.Now - endTime).TotalMilliseconds;
            Vector2 vector = new Vector2(startPosition, endPosition);

            if (timeBetweenNowAndLastMove < DELAY_BEFORE_MOUSE_UP_IN_MILLISECONDS && !vector.IsZero)
            {
                double time = (endTime - startTime).TotalSeconds;
                time = (time == 0) ? 0.001 : time;

                double distance = vector.Length / pixelsPerMeter;

                double intialVelocity = distance / time;

                double expectedDistance = ((intialVelocity * intialVelocity) / (2 * COEFFICIENT_OF_SLIDING_FRICTION * GRAVITATIONAL_ACCELERATION));
                double expectedTime     = (2 * expectedDistance) / intialVelocity;

                double shiftX = Math.Round(vector.LengthX * expectedDistance / distance);
                double shiftY = Math.Round(vector.LengthY * expectedDistance / distance);

                // New Inertial Motion Vector
                Vector2 imVector       = new Vector2(endPosition, shiftX, shiftY).Round();
                double  expectedLength = imVector.Length;

                Rect bounds = hostBounds.Add(-windowBounds.Width, -windowBounds.Height);

                if (bounds.Contains(endPosition))
                {
                    imVector = EnsureEndPointInBounds(imVector, bounds).Round();
                }
                else if (hostBounds.Contains(endPosition))
                {
                    imVector = EnsureEndPointInBounds(imVector, hostBounds).Round();
                }

                // Reduce expected time if the Inertial Motion Vector was truncated by the bounds
                double realTime = (expectedLength == 0) ? 0 : (expectedTime * imVector.Length / expectedLength);

                var motion = new InertialMotion()
                {
                    Seconds        = realTime,
                    EndPosition    = imVector.End,
                    EasingFunction = new CubicEase()
                    {
                        EasingMode = EasingMode.EaseOut
                    }
                };

                return(motion);
            }

            return(null);
        }