1. Oscar de Groot Martijn Nijenhof Ales Sturala Christina Manteli

2.  GameBoard:  A grid of w(columns) x h(rows) ▪ w,h  {1,2,3,..}  A collection of cells  Cell:  Square shaped  Cell state can be either Filled or Empty  Each cell has a coordinate c(x,y) on the GameBoard  c : 0 ≤ c.x ≤ w and 0 ≤ c.y ≤ h

3.  Tile:  A connected set of Filled cells c 1..n (x,y) on the GameBoard ▪ Tile  GameBoard ▪ 4 Rotation states ▪ 2 Shift directions  Only one Tile present at any time  Content  All Filled cells except the Tile

4.  Clock tick  TryMoveDown  RemoveRow  User Input  TryRotateLeft  TryRotateRight  TryShiftLeft  TryShiftRight

5.  A Tile can be rotated  Desired: tiles rotate around center of gravity, point symmetric tiles rotated 180° should be in their original positions. ▪ Too complicated.  Each tile must have a specified ‘center of rotation’, which is the cell it rotates around.  Clockwise (TryRotateRight) or counter clockwise (TryRotateLeft)

6.  A Tile can be rotated  RotateLeft: Rotate the Tile 90 o counter clockwise around the center of rotation.  TryRotateLeft: ▪ RotatedTile = result of the RotateLeft operation ▪ If RotatedTile  Content =  and RotatedTile  GameBoard then RotateLeft(Tile)  Same holds for RotateRight and TryRotateRight

7.  Tile can be shifted into 3 directions: Left, Right, Down  ShiftLeft:  c coordinate in Tile: c.x = c.x – 1  TryShiftLeft: ▪ ShiftedTile = result of the ShiftLeft operation ▪ If ShiftedTile  Content =  and ShiftedTile  GameBoard then ShiftLeft(Tile)  Same holds for ShiftRight and TryShiftRight

8.  MoveDown:  c coordinate in Tile: c.y = c.y - 1  TryMoveDown:  MovedTile = result of the MoveDown operation  if MovedTile  Content   or MovedTile  GameBoard then StuckTile()

9.  StuckTile:  Content = Content  Tile  CreateNewTile  CreateNewTile:  Create new Tile, where Tile  GameBoard and Tile  Content   and Tile.MaxYCoordinate = Gameboard.height | Game over

10.  RemoveRows ::  Row where every Row.cell==content:  remove all content from Row   c in Content where c.y > removed Row y- coordinate : c.y = c.y – 1