Improved Animations

public static const DEFAULT:uint = 0;
public static const IDLE:uint = 0;
public static const WALKING:uint = 1;

/**
 * Read sprites for versions 10.57.
 */
public static function readSprites(thing:ThingType, input:IDataInput):Boolean
{
    var isOutfit:Boolean = (thing.category == ThingCategory.OUTFIT);
    var groupCount:uint = isOutfit ? input.readUnsignedByte() : 1;

    for (var k:uint = 0; k < groupCount; k++)
    {
        var groupType:uint = isOutfit ? input.readUnsignedByte() : DEFAULT;
        var frameGroup:FrameGroup = new FrameGroup();

        frameGroup.width = input.readUnsignedByte();
        frameGroup.height = input.readUnsignedByte();

        if (frameGroup.width > 1 || frameGroup.height > 1)
            frameGroup.exactSize = input.readUnsignedByte();
        else
            frameGroup.exactSize = Sprite.DEFAULT_SIZE;

        frameGroup.layers = input.readUnsignedByte();
        frameGroup.patternX = input.readUnsignedByte();
        frameGroup.patternY = input.readUnsignedByte();
        frameGroup.patternZ = input.readUnsignedByte();
        frameGroup.frames = input.readUnsignedByte();

        var i:uint = 0;

        if (frameGroup.frames > 1)
        {
            frameGroup.isAnimation = true;

            var animationMode:uint = input.readUnsignedByte();
            var frameStrategy:int  = input.readInt();
            var startFrame:int = input.readByte();
            var frameDurations:Vector.<FrameDuration> = new Vector.<FrameDuration>(frameGroup.frames, true);

            for (i = 0; i < frameGroup.frames; i++)
            {
                var minimum:uint = input.readUnsignedInt();
                var maximum:uint = input.readUnsignedInt();
                frameDurations[i] = new FrameDuration(minimum, maximum);
            }

            frameGroup.animator = Animator.create(frameGroup.frames,
                                                  startFrame,
                                                  frameStrategy,
                                                  animationMode,
                                                  frameDurations);
        }

        var totalSprites:uint = frameGroup.getTotalSprites(); // width * height * layers * patternX * patternY * patternZ * frames
        if (totalSprites > 4096)
            throw new Error("A thing type has more than 4096 sprites.");

        frameGroup.spriteIndex = new Vector.<uint>(totalSprites, true);

        for (i = 0; i < totalSprites; i++)
            frameGroup.spriteIndex[i] = input.readUnsignedInt();

        var hasIdle:Boolean = (thing.frameGroups[IDLE] !== undefined);

        if (groupType == WALKING && (!hasIdle || hasIdle && thing.frameGroups[IDLE].frames == 0))
        {
            thing.frameGroups[IDLE] = frameGroup;
        }

        thing.frameGroups[groupType] = frameGroup;
    }

    return true;
}