/// <summary>
/// rotate row y=A by B shifts all of the pixels in row A (0 is the top row) right by B pixels.
/// Pixels that would fall off the right end appear at the left end of the row.
/// </summary>
/// <param name="instruction">e.g "y=5 by 20"</param>
public void ProcessRotateRow(RotateRowInstruction rotateRowInstruction)
{
int width = screenDisplay.GetLength(1);
bool[,] copyOfScreenDisplay = (bool[, ])screenDisplay.Clone();
for (int i = 0; i < width; i++)
{
screenDisplay[rotateRowInstruction.row, (i + rotateRowInstruction.shiftAmount) % width] = copyOfScreenDisplay[rotateRowInstruction.row, i];
}
}
public void ProcessLine(string line)
{
if (line.Substring(0, RectangleInstruction.RECTANGLE.Length).Equals(RectangleInstruction.RECTANGLE))
{
RectangleInstruction rectangleInstruction = new RectangleInstruction(line);
ProcessRectangleInstruction(rectangleInstruction);
}
else if (line.Substring(0, RotateRowInstruction.ROTATE_ROW.Length).Equals(RotateRowInstruction.ROTATE_ROW))
{
RotateRowInstruction rotateRowInstruction = new RotateRowInstruction(line, screenDisplay.GetLength(1));
ProcessRotateRow(rotateRowInstruction);
}
else if (line.Substring(0, RotateColumnInstruction.ROTATE_COLUMN.Length).Equals(RotateColumnInstruction.ROTATE_COLUMN))
{
RotateColumnInstruction rotateColumnInstruction = new RotateColumnInstruction(line, screenDisplay.GetLength(0));
ProcessRotateColumn(rotateColumnInstruction);
}
}