CandyTetris

Tetris built on the SugarCraft stack. SugarCraft runtime, CandySprinkles for the rounded borders and per-piece colours, deterministic 7-bag RNG, ghost piece, hard drop, hold, level-driven gravity ramp, line-clear scoring.

Run it

composer install
./bin/tetris         # Single player mode
./bin/tetris -v      # VS Computer mode
./bin/tetris --vs    # VS Computer mode (long form)

VS Computer Mode

Compete against an AI opponent in split-screen mode. When you clear lines, garbage rows are sent to the computer. When the computer clears lines, garbage rows are sent to you. Last player standing wins!

VS Mode Controls

Key	Action
← / →	Move left / right
↑ / x	Rotate clockwise
z	Rotate counter-cw
↓	Soft drop
Space	Hard drop
p	Pause / resume
q	Quit

The computer opponent uses weighted heuristics (board height, holes, gaps, lines) to make optimal moves.

Controls

Key	Action
← / →	Move left / right
↑ / x	Rotate clockwise
z	Rotate counter-cw
↓	Soft drop
Space	Hard drop
p	Pause / resume
q	Quit

Scoring

Line-clear scoring

Lines cleared	Base points × (level + 1)
1	40
2	100
3	300
4 (Tetris)	1200

Level rises every 10 lines. Gravity speeds up at every level — by level 9 pieces fall every 6 frames, by level 29+ they fall every frame. The frame-rate-agnostic Score::framesPerRow() is what the gravity tick consults.

T-Spin scoring

When a T piece is rotated into a position where two or more of its four diagonal corner cells are already filled (walls count as filled), it scores as a T-Spin:

Type	Base points
T-Spin	400 × (level + 1)
T-Spin Mini	100 × (level + 1)

T-Spin Mini is detected when exactly two front corners are filled (the side the piece entered from).

3-corner rule: A T-Spin is active when the locked T piece's final position differs in rotation from its pre-lock rotation, AND at least two of the four diagonal corner cells around the T are occupied (wall/out-of-bounds = occupied). See Scoring\TSpin::detect().

Back-to-Back (B2B) bonus

Consecutive Tetris clears or full T-Spins (non-mini) carry a 1.5× multiplier on the line-clear base points:

• 4-line Tetris after a prior Tetris → 1200 × 1.5 × (level + 1)
• Full T-Spin after a prior full T-Spin → 400 × 1.5 × (level + 1)

B2B resets when a 1–3 line clear or a T-Spin Mini breaks the streak.

Combo bonus

Consecutive line clears (regardless of type) build a combo counter — each combo step adds combo × 10 × (level + 1) bonus points. The counter resets to 0 on any clean (zero-line) piece placement.

Perfect clear bonus

When all lines are cleared at once and the board becomes completely empty, an additional +5000 × (level + 1) bonus is awarded.

Shared foundations

All game renderers build their playfield and score panel via candy-buffer. The 10×20 playfield is a canonical Buffer cell grid; per-tetromino background style and ghost-piece foreground style are applied per-cell. Buffer::withRegion composites the score panel over the playfield interior. Snapshot tests via candy-testing pin canonical game states (starting board, T-spin completion, pause overlay).