caching and rendering spritesheets doesn't work - arrays

Question

I'd like to cache my spritesheet (tilesheet) into an array. I do this because every spritesheet shall be cached inside of an array so my objects can pull their tiles from them easily. But my cache doesn't seem to work because absolutely nothing gets rendered out of it. I can't see anything.
There is something inside my cache (likely bitmapData) and it is not null so currently I don't know where the problem might be.
Can someone help me out with this issue, please?
this function shall render each tile of an array to a background via copypixels
public function renderCachedTile(canvasBitmapData:BitmapData, tileArray:Array):void
{
tileCache = tileArray;
tileArray = [];
x = nextX;
y = nextY;
point.x = x;
point.y = y;
tileRect.x = tileWidth;
tileRect.y = tileHeight;
if (animationCount >= animationDelay)
{
animationCount = 0;
if(reverse)
{
currentTile--;
if (currentTile < 1)
{
currentTile = tilesLength - 1;
}
} else {
currentTile++;
if (currentTile >= tilesLength - 1)
{
currentTile = 0;
}
}
} else {
animationCount++;
}
canvasBitmapData.lock();
canvasBitmapData.copyPixels(tileCache[currentTile], tileRect, point);
canvasBitmapData.unlock();
}
this function 'separates' my spritesheet into tiles and throws them into an array
private function tileToCache():void {
var tileBitmapData:BitmapData = new BitmapData(tileWidth, tileHeight, true, 0x00000000);
var tilePt:Point = new Point(0, 0);
var tileRect:Rectangle = new Rectangle;
tileCache = [];
for (var tileCtr:int = 0; tileCtr < tilesLength; tileCtr++) {
tileBitmapData.lock();
tileRect.x = int((tileCtr % spritesPerRow)) * tileWidth;
tileRect.y = int((tileCtr / spritesPerRow)) * tileHeight;
tileBitmapData.copyPixels(tileSheet, tileRect, tilePt);
tileBitmapData.unlock();
tileCache.push(tileBitmapData);
}
}

Answer 1

Unless there is code missing from your example, in your tileToCache you instantiate and use tileRect without defining a width and height:
private function tileToCache():void {
var tileRect:Rectangle = new Rectangle;
/* ... */
tileBitmapData.copyPixels(tileSheet, tileRect, tilePt);
If your source was at 0, 0 I presume you would want:
var tileRect:Rectangle = new Rectangle(0, 0, tileWidth, tileHeight);