Tetris Piece Rotation Algorithm

Question

What are the best algorithms (and explanations) for representing and rotating the pieces of a tetris game? I always find the piece rotation and representation schemes confu

Answer 1

Since there are only 4 possible orientations for each shape, why not use an array of states for the shape and rotating CW or CCW simply increments or decrements the index of the shape state (with wraparound for the index)? I would think that might be quicker than performing rotation calculations and whatnot.