public override void Render()
{
if (Width <= 0 || Height <= 0)
{
throw new InvalidOperationException($"{nameof(Render)}: arranger dimensions for '{Arranger.Name}' are too small to render " +
$"({Width}, {Height})");
}
if (Width * Height != Image.Length)
{
Image = new byte[Width * Height];
}
// TODO: Handle undefined elements explicitly and clear image subsections
Array.Clear(Image, 0, Image.Length);
var locations = Arranger.EnumerateElementLocationsWithinPixelRange(Left, Top, Width, Height);
var imageRect = new Rectangle(Left, Top, Width, Height);
foreach (var location in locations)
{
var el = Arranger.GetElement(location.X, location.Y);
if (el is ArrangerElement element && element.Codec is IIndexedCodec codec)
{
var encodedBuffer = codec.ReadElement(element);
// TODO: Detect reads past end of file more gracefully
if (encodedBuffer.Length == 0)
{
continue;
}
var elementRect = new Rectangle(element.X1, element.Y1, element.Width, element.Height);
elementRect.Intersect(imageRect);
if (elementRect.IsEmpty)
{
continue;
}
int minX = Math.Clamp(element.X1, Left, Right - 1);
int maxX = Math.Clamp(element.X2, Left, Right - 1);
int minY = Math.Clamp(element.Y1, Top, Bottom - 1);
int maxY = Math.Clamp(element.Y2, Top, Bottom - 1);
int deltaX = minX - element.X1;
int deltaY = minY - element.Y1;
var decodedImage = codec.DecodeElement(element, encodedBuffer);
decodedImage.RotateArray2D(element.Rotation);
decodedImage.MirrorArray2D(element.Mirror);
for (int y = 0; y <= maxY - minY; y++)
{
int destidx = (element.Y1 + deltaY + y - Top) * Width + (element.X1 + deltaX - Left);
for (int x = 0; x <= maxX - minX; x++)
{
Image[destidx] = decodedImage[y + deltaY, x + deltaX];
destidx++;
}
}
}