Tetris

What if we had no grid?

Up and running

Install node and yarn. Then:

yarn install
yarn global add browserify budo
./scripts/dev.sh

a shape
- has a list of occupied cell coordinates (by x,y) at reference orientation
- has presentation info (like color)
- has a name?
the basic shapes: line, square, left-s, right-s, left-l, right-l, tee
a piece
- is of a shape
- at an orientation (0-3)
- at a position (x:0-10; y:0-20; 0,0 at top left)
a dead cell
- is of a shape (e.g., for color)
- at x,y
a game
- has a list of dead cells
- has a live piece (could be 1st/last in list?)

on start:
- add/make live piece:
  - random shape
  - x position near middle
  - if would violate, do end
on tick or down move:
- move down 1
- handle potential landing
on lateral move (left/right):
- unless would violate
- move piece 1 left/right
on rotate:
- unless would violate
- increment live piece orientation 1, modulo 4
- handle potential landing

would violate: given a candidate piece whether:
- piece extent would exceed x-boundary (0,10)
- piece would overlap a dead cell
potential landing:
- if live piece: did land:
  - add its cells to dead cell list
  - for any complete (gapless, edge-to-edge) row in dead cell list
    - remove all cells in the row
    - move all cells above the row down
  - increment score by some function of count of lines removed
  - do start
did land: whether any:
- any cell of live piece is any:
  - directly above (y-1) that of any dead cell
  - on bottom row

on any change, render grid of cells:
- for each x,y, display for shape in that x,y
tick every second or so