/// <summary>
/// Updates the controller.
/// </summary>
/// <param name="time">Time elapsed since the last call to <see cref="UltravioletContext.Update(UltravioletTime)"/>.</param>
public void Update(UltravioletTime time)
{
if (IsPlaying)
{
// If the current animation has no frames, there's no need to update.
if (animation.Frames.Count < 1)
{
if (defaultAnimation != null)
PlayAnimation(defaultAnimation);
return;
}
// Calculate the duration of the current frame. If we have a specified playback time
// for this animation, then we normalize the frame duration and multiply by the playback time.
var duration = playbackTime ?? 0.0;
if (animation.Frames.Count > 1)
{
duration = (playbackTime.HasValue) ?
(frame.Duration / (float)animation.Frames.Duration) * playbackTime.GetValueOrDefault() :
(frame.Duration);
}
// Update the animation timer and advance to the next frame if necessary.
timer += time.ElapsedTime.TotalMilliseconds;
if (timer >= duration)
{
timer -= duration;
// Have we reached the end of our frame list?
if (frameIndex + 1 == animation.Frames.Count)
{
// If this is a fire-and-forget animation, play the default.
if (defaultAnimation != null)
{
PlayAnimation(defaultAnimation);
return;
}
// If this is a non-repeating animation, stop it.
if (animation.Repeat == SpriteAnimationRepeat.None)
{
StopAnimation();
return;
}
// Othewise, return to the first frame of the animation.
frameIndex = 0;
frame = animation.Frames[frameIndex];
}
else
{
// Advance to the next frame of the animation.
frameIndex++;
frame = animation.Frames[frameIndex];
}
}
}
}
/// <summary>
/// Resets the controller's current animation to its default state.
/// </summary>
public void ResetAnimation()
{
this.timer = 0.0;
this.frame = (animation == null || animation.Frames.Count == 0) ? null : animation.Frames[0];
this.frameIndex = 0;
}
/// <summary>
/// Stops the controller's current animation.
/// </summary>
public void StopAnimation()
{
this.animation = null;
this.defaultAnimation = null;
this.playbackTime = null;
this.timer = 0.0;
this.frame = null;
}
/// <summary>
/// Draws a single animation frame.
/// </summary>
/// <param name="frame">The <see cref="SpriteFrame"/> to draw.</param>
/// <param name="destinationRectangle">A rectangle which indicates where on the screen the sprite will be drawn.</param>
/// <param name="color">The sprite's tint color.</param>
/// <param name="rotation">The sprite's rotation in radians.</param>
/// <param name="effects">The sprite's rendering effects.</param>
/// <param name="layerDepth">The sprite's layer depth.</param>
public void DrawFrame(SpriteFrame frame, Rectangle destinationRectangle, Color color, Single rotation, SpriteEffects effects, Single layerDepth)
{
if (SpriteBatch == null)
throw new InvalidOperationException(PresentationStrings.DrawingContextDoesNotHaveSpriteBatch);
SpriteBatch.DrawFrame(frame, destinationRectangle, color * Opacity, rotation, effects, layerDepth);
}
