Пример #1
0
        /// <summary>
        /// Gets the cycle offset for a time value.
        /// </summary>
        /// <typeparam name="T">The type of animation value.</typeparam>
        /// <param name="time">The time value.</param>
        /// <param name="startTime">The start time.</param>
        /// <param name="endTime">The end time.</param>
        /// <param name="startValue">In: The animation value at <paramref name="startTime"/>.</param>
        /// <param name="endValue">In: The animation value at <paramref name="endTime"/>.</param>
        /// <param name="traits">The traits of the animation value.</param>
        /// <param name="loopBehavior">The post-loop behavior.</param>
        /// <param name="cycleOffset">
        /// Out: The cycle offset.
        /// </param>
        /// <remarks>
        /// The cycle offset is <see cref="IAnimationValueTraits{T}.SetIdentity"/> if the
        /// <see cref="LoopBehavior"/> is unequal to <see cref="LoopBehavior.CycleOffset"/> or if the
        /// <paramref name="time"/> is in the regular cycle (between the first and the last key frame).
        /// </remarks>
        internal static void GetCycleOffset <T>(TimeSpan time,
                                                TimeSpan startTime, TimeSpan endTime,
                                                ref T startValue, ref T endValue,
                                                IAnimationValueTraits <T> traits,
                                                LoopBehavior loopBehavior,
                                                ref T cycleOffset)
        {
            Debug.Assert(endTime > startTime, "Invalid start and end time.");
            TimeSpan length = endTime - startTime;

            // Handle cycle offset.
            if (loopBehavior == LoopBehavior.CycleOffset && length != TimeSpan.Zero)
            {
                traits.Invert(ref startValue, ref startValue);
                traits.Add(ref startValue, ref endValue, ref cycleOffset);

                if (time < startTime)
                {
                    long numberOfPeriods = (time.Ticks - endTime.Ticks) / length.Ticks;
                    Debug.Assert(numberOfPeriods < 0, "Negative number of periods expected.");
                    traits.Multiply(ref cycleOffset, (int)numberOfPeriods, ref cycleOffset);
                }
                else if (time > endTime)
                {
                    long numberOfPeriods = (time.Ticks - startTime.Ticks) / length.Ticks;
                    Debug.Assert(numberOfPeriods > 0, "Positive number of periods expected.");
                    traits.Multiply(ref cycleOffset, (int)numberOfPeriods, ref cycleOffset);
                }
                else
                {
                    traits.SetIdentity(ref cycleOffset);
                }
            }
        }
Пример #2
0
 public static T Add <T>(this IAnimationValueTraits <T> traits, T value0, T value1)
 {
     traits.Add(ref value0, ref value1, ref value0);
     return(value0);
 }