Falling Blocks

About Falling Blocks

Falling Blocks is our version of the classic falling-piece puzzle first made in the Soviet Union in 1984 and copied, cloned and taught in programming courses ever since. Seven shapes, each made of four squares, drop one at a time into a well ten squares wide and twenty deep. You slide and rotate each piece as it falls. When a row is filled from wall to wall it disappears and everything above it drops down. When the pile reaches the top, the game is over.

The pieces come from a shuffled bag of 28, four of each shape, so a long drought of the straight piece is rare. The game speeds up slightly with every row you clear, starting at one step every 0.6 seconds and getting as quick as one step every 0.1 seconds.

How to play Falling Blocks

1. Press Start, or Space. The first piece appears at the top.
2. Move it with the left and right arrow keys, or the arrow buttons under the board.
3. Rotate it with the up arrow or the rotate button. A tap on the board also rotates.
4. Press down to drop one row faster, or Space or Drop to drop it straight to the bottom.
5. Fill complete rows to clear them. P or Esc pauses; the game also pauses by itself when you switch tabs.

Scoring

Every piece that lands scores 10. Clearing one row scores 100, two at once 200, three at once 400 and four at once 800, so building up a deep stack and clearing four rows with one straight piece is worth twice as much as clearing those rows one by one.

Tips

Keep the surface flat and leave one column open at the side for the straight piece. Look at the next piece in the side panel before placing the current one. Avoid covering holes, because a hole under a filled square cannot be reached until every row above it is cleared.

The code behind this page is a teaching example in its own right: every piece is stored as a 16-bit number, one bit per square of a 4 by 4 box, and one number per rotation. Reading it is a good first exercise in bit masks for a computer engineering student.