/// <summary>
/// Updates the drawable. If the drawable changed in any
/// visible manner, then this returns true.
/// </summary>
public bool Update(DrawableState state)
{
// Don't bother if we only have one frame
if (tile.Count == 1)
{
return(false);
}
// Figure out the different in time
TileFrame frame = tile.Frames[state.Frame];
long now = DateTime.UtcNow.Ticks / 10000;
long diff = now - state.LastUpdate;
// If not enough time has passed, just move on
if (diff < frame.Delay)
{
return(false);
}
// We need to move to the next one
long fdiff = diff - frame.Delay;
if (fdiff > frame.Delay)
{
fdiff %= frame.Delay;
}
state.Frame = frame.NextFrame;
state.LastUpdate = now + fdiff;
return(true);
}
/// <summary>
/// Reads a single frame into memory.
/// </summary>
private void ReadFrame(
Tile tile,
XmlTextReader xtr)
{
// Grab the sequence
int seq = Int32.Parse(xtr["sequence"]);
TileFrame frame = null;
try
{
frame = tile.Frames[seq];
}
catch (Exception)
{
return;
}
// Try to read in the rest of the optional elements
if (!String.IsNullOrEmpty(xtr["delay-ms"]))
{
frame.Delay = Int32.Parse(xtr["delay-ms"]);
}
if (!String.IsNullOrEmpty(xtr["next-frame"]))
{
frame.NextFrame = Int32.Parse(xtr["next-frame"]);
}
if (!String.IsNullOrEmpty(xtr["random"]))
{
frame.Random = Boolean.Parse(xtr["random"]);
}
}
/// <summary>
/// Randomizes the drawable state based on this specific
/// drawable.
/// </summary>
public void Randomize(DrawableState state)
{
// Pick a random frame. We loop this since a frame may not
// be randomizeable (the Random property is false).
while (true)
{
// Pick one
int seq = random.Next(0, tile.Count - 1);
TileFrame frame = tile.Frames[seq];
if (frame.Random)
{
// We can use this as a random. We also randomize
// the last update to have not everything updating
// at the same time.
state.Frame = seq;
state.LastUpdate = DateTime.UtcNow.Ticks / 10000 +
random.Next(0, frame.Delay);
return;
}
}
}
