⚠️ Warning: This is a draft ⚠️
This means it might contain formatting issues, incorrect code, conceptual problems, or other severe issues.
If you want to help to improve and eventually enable this page, please fork RosettaGit's repository and open a merge request on GitHub.
{{draft task|Games}}{{wikipedia|Snake_(video_game)}}
[[wp:Snake_(video_game)|Snake]] is a game where the player maneuvers a line which grows in length every time the snake reaches a food source.
;Task
Implement a variant of the Snake game, in any interactive environment, in which a sole player attempts to eat items by running into them with the head of the snake. Each item eaten makes the snake longer and a new item is randomly generated somewhere else on the plane. The game ends when the snake attempts to eat himself.
BASIC
=
ZX Spectrum Basic
= By ancient tradition, the controls are Q for up, A for down, O for left, and P for right.
A screenshot is [http://www.edmundgriffiths.com/spectrumsnake.jpg here].
Note that lines 10 to 210 and 580 to 890—more than half the program—define graphics characters for the snake's head (facing in different directions) and for its food. If you're happy to make do with characters from the standard character set, you can easily adapt lines 220 to 570 to work on their own. The things the snake eats are supposed to be apples, although they don't look too much like them.
10 FOR i=0 TO 7
20 READ bits
30 POKE USR "L"+i,bits
40 NEXT i
50 FOR i=0 TO 7
60 READ bits
70 POKE USR "R"+i,bits
80 NEXT i
90 FOR i=0 TO 7
100 READ bits
110 POKE USR "P"+i,bits
120 NEXT i
130 RESTORE 740
140 FOR i=7 TO 0 STEP -1
150 READ bits
160 POKE USR "D"+i,bits
170 NEXT i
180 FOR i=0 TO 7
190 READ bits
200 POKE USR "F"+i, bits
210 NEXT i
220 PAPER 0
230 CLS
240 LET snakex=19
250 LET snakey=15
260 LET dx=-1
270 LET dy=0
280 LET s$=CHR$ 15+CHR$ 20+CHR$ 15+CHR$ 21
290 LET foodx=INT (RND*32)
300 LET foody=INT (RND*22)
310 IF SCREEN$ (foody,foodx)<>" " THEN GO TO 290
320 INK 2
330 PRINT AT foody,foodx;CHR$ 149
340 INK 4
350 INVERSE 1
360 PRINT AT CODE s$,CODE s$(1);"#"
370 INVERSE 0
380 IF INKEY$="q" AND dy=0 THEN LET dx=0: LET dy=-1
390 IF INKEY$="a" AND dy=0 THEN LET dx=0: LET dy=1
400 IF INKEY$="o" AND dx=0 THEN LET dx=-1: LET dy=0
410 IF INKEY$="p" AND dx=0 THEN LET dx=1: LET dy=0
420 IF dx=-1 THEN PRINT AT snakey,snakex;CHR$ 155
430 IF dx=1 THEN PRINT AT snakey,snakex;CHR$ 161
440 IF dy=1 THEN PRINT AT snakey,snakex;CHR$ 159
450 IF dy=-1 THEN PRINT AT snakey,snakex;CHR$ 147
460 LET s$=CHR$ snakey+CHR$ snakex+s$
470 IF snakex=foodx AND snakey=foody THEN GO TO 290
480 PRINT AT CODE s$(LEN s$-1),CODE s$(LEN s$);" "
490 LET s$=s$( TO LEN s$-2)
500 LET snakex=snakex+dx
510 LET snakey=snakey+dy
520 IF snakex=-1 THEN LET snakex=31
530 IF snakex=32 THEN LET snakex=0
540 IF snakey=-1 THEN LET snakey=21
550 IF snakey=22 THEN LET snakey=0
560 IF SCREEN$ (snakey,snakex)="#" THEN STOP
570 GO TO 340
580 DATA BIN 00001111
590 DATA BIN 00111111
600 DATA BIN 01110011
610 DATA BIN 11110011
620 DATA BIN 11111111
630 DATA BIN 01111111
640 DATA BIN 00000111
650 DATA BIN 00011111
660 DATA BIN 11110000
670 DATA BIN 11111100
680 DATA BIN 11001110
690 DATA BIN 11001111
700 DATA BIN 11111111
710 DATA BIN 11111110
720 DATA BIN 11100000
730 DATA BIN 11111000
740 DATA BIN 00011000
750 DATA BIN 00111100
760 DATA BIN 01111100
770 DATA BIN 01111101
780 DATA BIN 11001101
790 DATA BIN 11001111
800 DATA BIN 11111111
810 DATA BIN 11111111
820 DATA BIN 00000100
830 DATA BIN 00001000
840 DATA BIN 01101011
850 DATA BIN 11111100
860 DATA BIN 11111100
870 DATA BIN 11111100
880 DATA BIN 01111111
890 DATA BIN 00110110
C++
Simple Windows console implementation. [[File:SnakeCpp.png|200px|thumb|right]]
#include <windows.h>
#include <ctime>
#include <iostream>
#include <string>
const int WID = 60, HEI = 30, MAX_LEN = 600;
enum DIR { NORTH, EAST, SOUTH, WEST };
class snake {
public:
snake() {
console = GetStdHandle( STD_OUTPUT_HANDLE ); SetConsoleTitle( "Snake" );
COORD coord = { WID + 1, HEI + 2 }; SetConsoleScreenBufferSize( console, coord );
SMALL_RECT rc = { 0, 0, WID, HEI + 1 }; SetConsoleWindowInfo( console, TRUE, &rc );
CONSOLE_CURSOR_INFO ci = { 1, false }; SetConsoleCursorInfo( console, &ci );
}
void play() {
std::string a;
while( 1 ) {
createField(); alive = true;
while( alive ) { drawField(); readKey(); moveSnake(); Sleep( 50 ); }
COORD c = { 0, HEI + 1 }; SetConsoleCursorPosition( console, c );
SetConsoleTextAttribute( console, 0x000b );
std::cout << "Play again [Y/N]? "; std::cin >> a;
if( a.at( 0 ) != 'Y' && a.at( 0 ) != 'y' ) return;
}
}
private:
void createField() {
COORD coord = { 0, 0 }; DWORD c;
FillConsoleOutputCharacter( console, ' ', ( HEI + 2 ) * 80, coord, &c );
FillConsoleOutputAttribute( console, 0x0000, ( HEI + 2 ) * 80, coord, &c );
SetConsoleCursorPosition( console, coord );
int x = 0, y = 1; for( ; x < WID * HEI; x++ ) brd[x] = 0;
for( x = 0; x < WID; x++ ) {
brd[x] = brd[x + WID * ( HEI - 1 )] = '+';
}
for( ; y < HEI; y++ ) {
brd[0 + WID * y] = brd[WID - 1 + WID * y] = '+';
}
do {
x = rand() % WID; y = rand() % ( HEI >> 1 ) + ( HEI >> 1 );
} while( brd[x + WID * y] );
brd[x + WID * y] = '@';
tailIdx = 0; headIdx = 4; x = 3; y = 2;
for( int c = tailIdx; c < headIdx; c++ ) {
brd[x + WID * y] = '#';
snk[c].X = 3 + c; snk[c].Y = 2;
}
head = snk[3]; dir = EAST; points = 0;
}
void readKey() {
if( GetAsyncKeyState( 39 ) & 0x8000 ) dir = EAST;
if( GetAsyncKeyState( 37 ) & 0x8000 ) dir = WEST;
if( GetAsyncKeyState( 38 ) & 0x8000 ) dir = NORTH;
if( GetAsyncKeyState( 40 ) & 0x8000 ) dir = SOUTH;
}
void drawField() {
COORD coord; char t;
for( int y = 0; y < HEI; y++ ) {
coord.Y = y;
for( int x = 0; x < WID; x++ ) {
t = brd[x + WID * y]; if( !t ) continue;
coord.X = x; SetConsoleCursorPosition( console, coord );
if( coord.X == head.X && coord.Y == head.Y ) {
SetConsoleTextAttribute( console, 0x002e );
std::cout << 'O'; SetConsoleTextAttribute( console, 0x0000 );
continue;
}
switch( t ) {
case '#': SetConsoleTextAttribute( console, 0x002a ); break;
case '+': SetConsoleTextAttribute( console, 0x0019 ); break;
case '@': SetConsoleTextAttribute( console, 0x004c ); break;
}
std::cout << t; SetConsoleTextAttribute( console, 0x0000 );
}
}
std::cout << t; SetConsoleTextAttribute( console, 0x0007 );
COORD c = { 0, HEI }; SetConsoleCursorPosition( console, c );
std::cout << "Points: " << points;
}
void moveSnake() {
switch( dir ) {
case NORTH: head.Y--; break;
case EAST: head.X++; break;
case SOUTH: head.Y++; break;
case WEST: head.X--; break;
}
char t = brd[head.X + WID * head.Y];
if( t && t != '@' ) { alive = false; return; }
brd[head.X + WID * head.Y] = '#';
snk[headIdx].X = head.X; snk[headIdx].Y = head.Y;
if( ++headIdx >= MAX_LEN ) headIdx = 0;
if( t == '@' ) {
points++; int x, y;
do {
x = rand() % WID; y = rand() % ( HEI >> 1 ) + ( HEI >> 1 );
} while( brd[x + WID * y] );
brd[x + WID * y] = '@'; return;
}
SetConsoleCursorPosition( console, snk[tailIdx] ); std::cout << ' ';
brd[snk[tailIdx].X + WID * snk[tailIdx].Y] = 0;
if( ++tailIdx >= MAX_LEN ) tailIdx = 0;
}
bool alive; char brd[WID * HEI];
HANDLE console; DIR dir; COORD snk[MAX_LEN];
COORD head; int tailIdx, headIdx, points;
};
int main( int argc, char* argv[] ) {
srand( static_cast<unsigned>( time( NULL ) ) );
snake s; s.play(); return 0;
}
Go
This uses the [https://github.com/nsf/termbox-go termbox] package for terminal input and output. This makes the code fairly cross-platform, it successfully built for FreeBSD, OpenBSD, NetBSD, DragonFly BSD, Linux, MS Windows, and MacOS (tested on FreeBSD and MS Windows).
package main
import (
"errors"
"fmt"
"log"
"math/rand"
"time"
termbox "github.com/nsf/termbox-go"
)
func main() {
rand.Seed(time.Now().UnixNano())
score, err := playSnake()
if err != nil {
log.Fatal(err)
}
fmt.Println("Final score:", score)
}
type snake struct {
body []position // tail to head positions of the snake
heading direction
width, height int
cells []termbox.Cell
}
type position struct {
X int
Y int
}
type direction int
const (
North direction = iota
East
South
West
)
func (p position) next(d direction) position {
switch d {
case North:
p.Y--
case East:
p.X++
case South:
p.Y++
case West:
p.X--
}
return p
}
func playSnake() (int, error) {
err := termbox.Init()
if err != nil {
return 0, err
}
defer termbox.Close()
termbox.Clear(fg, bg)
termbox.HideCursor()
s := &snake{
// It would be more efficient to use a circular
// buffer instead of a plain slice for s.body.
body: make([]position, 0, 32),
cells: termbox.CellBuffer(),
}
s.width, s.height = termbox.Size()
s.drawBorder()
s.startSnake()
s.placeFood()
s.flush()
moveCh, errCh := s.startEventLoop()
const delay = 125 * time.Millisecond
for t := time.NewTimer(delay); ; t.Reset(delay) {
var move direction
select {
case err = <-errCh:
return len(s.body), err
case move = <-moveCh:
if !t.Stop() {
<-t.C // handles race between moveCh and t.C
}
case <-t.C:
move = s.heading
}
if s.doMove(move) {
time.Sleep(1 * time.Second)
break
}
}
return len(s.body), err
}
func (s *snake) startEventLoop() (<-chan direction, <-chan error) {
moveCh := make(chan direction)
errCh := make(chan error, 1)
go func() {
defer close(errCh)
for {
switch ev := termbox.PollEvent(); ev.Type {
case termbox.EventKey:
switch ev.Ch { // WSAD and HJKL movement
case 'w', 'W', 'k', 'K':
moveCh <- North
case 'a', 'A', 'h', 'H':
moveCh <- West
case 's', 'S', 'j', 'J':
moveCh <- South
case 'd', 'D', 'l', 'L':
moveCh <- East
case 0:
switch ev.Key { // Cursor key movement
case termbox.KeyArrowUp:
moveCh <- North
case termbox.KeyArrowDown:
moveCh <- South
case termbox.KeyArrowLeft:
moveCh <- West
case termbox.KeyArrowRight:
moveCh <- East
case termbox.KeyEsc: // Quit
return
}
}
case termbox.EventResize:
// TODO
errCh <- errors.New("terminal resizing unsupported")
return
case termbox.EventError:
errCh <- ev.Err
return
case termbox.EventInterrupt:
return
}
}
}()
return moveCh, errCh
}
func (s *snake) flush() {
termbox.Flush()
s.cells = termbox.CellBuffer()
}
func (s *snake) getCellRune(p position) rune {
i := p.Y*s.width + p.X
return s.cells[i].Ch
}
func (s *snake) setCell(p position, c termbox.Cell) {
i := p.Y*s.width + p.X
s.cells[i] = c
}
func (s *snake) drawBorder() {
for x := 0; x < s.width; x++ {
s.setCell(position{x, 0}, border)
s.setCell(position{x, s.height - 1}, border)
}
for y := 0; y < s.height-1; y++ {
s.setCell(position{0, y}, border)
s.setCell(position{s.width - 1, y}, border)
}
}
func (s *snake) placeFood() {
for {
// a random empty cell
x := rand.Intn(s.width-2) + 1
y := rand.Intn(s.height-2) + 1
foodp := position{x, y}
r := s.getCellRune(foodp)
if r != ' ' {
continue
}
s.setCell(foodp, food)
return
}
}
func (s *snake) startSnake() {
// a random cell somewhat near the center
x := rand.Intn(s.width/2) + s.width/4
y := rand.Intn(s.height/2) + s.height/4
head := position{x, y}
s.setCell(head, snakeHead)
s.body = append(s.body[:0], head)
s.heading = direction(rand.Intn(4))
}
func (s *snake) doMove(move direction) bool {
head := s.body[len(s.body)-1]
s.setCell(head, snakeBody)
head = head.next(move)
s.heading = move
s.body = append(s.body, head)
r := s.getCellRune(head)
s.setCell(head, snakeHead)
gameOver := false
switch r {
case food.Ch:
s.placeFood()
case border.Ch, snakeBody.Ch:
gameOver = true
fallthrough
case empty.Ch:
s.setCell(s.body[0], empty)
s.body = s.body[1:]
default:
panic(r)
}
s.flush()
return gameOver
}
const (
fg = termbox.ColorWhite
bg = termbox.ColorBlack
)
// Symbols to use.
// Could use Unicode instead of simple ASCII.
var (
empty = termbox.Cell{Ch: ' ', Bg: bg, Fg: fg}
border = termbox.Cell{Ch: '+', Bg: bg, Fg: termbox.ColorBlue}
snakeBody = termbox.Cell{Ch: '#', Bg: bg, Fg: termbox.ColorGreen}
snakeHead = termbox.Cell{Ch: 'O', Bg: bg, Fg: termbox.ColorYellow | termbox.AttrBold}
food = termbox.Cell{Ch: '@', Bg: bg, Fg: termbox.ColorRed}
)
Haskell
{-# LANGUAGE TemplateHaskell #-}
import Control.Monad.Random (getRandomRs)
import Graphics.Gloss.Interface.Pure.Game
import Lens.Micro ((%~), (^.), (&), set)
import Lens.Micro.TH (makeLenses)
--------------------------------------------------------------------------------
-- all data types
data Snake = Snake { _body :: [Point], _direction :: Point }
makeLenses ''Snake
data World = World { _snake :: Snake , _food :: [Point]
, _score :: Int , _maxScore :: Int }
makeLenses ''World
--------------------------------------------------------------------------------
-- everything snake can do
moves (Snake b d) = Snake (step b d : init b) d
eats (Snake b d) = Snake (step b d : b) d
bites (Snake b _) = any (== head b)
step ((x,y):_) (a,b) = (x+a, y+b)
turn (x',y') (Snake b (x,y)) | (x+x',y+y') == (0,0) = Snake b (x,y)
| otherwise = Snake b (x',y')
--------------------------------------------------------------------------------
-- all randomness
createWorld = do xs <- map fromIntegral <$> getRandomRs (2, 38 :: Int)
ys <- map fromIntegral <$> getRandomRs (2, 38 :: Int)
return (Ok, World snake (zip xs ys) 0 0)
where
snake = Snake [(20, 20)] (1,0)
-------------------------------------------------------------------------------
-- A tyny DSL for declarative description of business logic
data Status = Ok | Fail | Stop
continue = \x -> (Ok, x)
stop = \x -> (Stop, x)
f >>> g = \x -> case f x of { (Ok, y) -> g y; b -> b } -- chain composition
f <|> g = \x -> case f x of { (Fail, _) -> g x; b -> b } -- alternative
p ==> f = \x -> if p x then f x else (Fail, x) -- condition
l .& f = continue . (l %~ f) -- modification
l .= y = continue . set l y -- setting
--------------------------------------------------------------------------------
-- all business logic
updateWorld _ = id >>> (snakeEats <|> snakeMoves)
where
snakeEats = (snakeFindsFood ==> (snake .& eats)) >>>
(score .& (+1)) >>> (food .& tail)
snakeMoves = (snakeBitesTail ==> stop) <|>
(snakeHitsWall ==> stop) <|>
(snake .& moves)
snakeFindsFood w = (w^.snake & moves) `bites` (w^.food & take 1)
snakeBitesTail w = (w^.snake) `bites` (w^.snake.body & tail)
snakeHitsWall w = (w^.snake.body) & head & isOutside
isOutside (x,y) = or [x <= 0, 40 <= x, y <= 0, 40 <= y]
--------------------------------------------------------------------------------
-- all event handing
handleEvents e (s,w) = f w
where f = case s of
Ok -> case e of
EventKey (SpecialKey k) _ _ _ -> case k of
KeyRight -> snake .& turn (1,0)
KeyLeft -> snake .& turn (-1,0)
KeyUp -> snake .& turn (0,1)
KeyDown -> snake .& turn (0,-1)
_-> continue
_-> continue
_-> \w -> w & ((snake.body) .= [(20,20)]) >>>
(maxScore .& max (w^.score)) >>> (score .= 0)
--------------------------------------------------------------------------------
-- all graphics
renderWorld (s, w) = pictures [frame, color c drawSnake, drawFood, showScore]
where c = case s of { Ok -> orange; _-> red }
drawSnake = foldMap (rectangleSolid 10 10 `at`) (w^.snake.body)
drawFood = color blue $ circleSolid 5 `at` (w^.food & head)
frame = color black $ rectangleWire 400 400
showScore = color orange $ scale 0.2 0.2 $ txt `at` (-80,130)
txt = Text $ mconcat ["Score: ", w^.score & show
," Maximal score: ", w^.maxScore & show]
at p (x,y) = Translate (10*x-200) (10*y-200) p
--------------------------------------------------------------------------------
main = do world <- createWorld
play inW white 7 world renderWorld handleEvents updateWorld
where inW = InWindow "The Snake" (400, 400) (10, 10)
'''Extra credit'''
It is easy to make snake to seek food automatically. Just change the first line of the updateWorld definition:
updateWorld _ = id >>> snakeSeeksFood >>> (snakeEats <|> snakeMoves)
and add local definition:
snakeSeeksFood w = w & snake .& turns optimalDirection
where
optimalDirection = minimumBy (comparing distanceToFood) safeTurns
safeTurns = filter safe [(x,y),(-y,x),(y,-x)] `ifEmpty` [(x,y)]
where (x,y) = w^.snake.direction
safe d = let w'' = w & snake %~ moves . turns d
in not (snakeBitesTail w'' || snakeHitsWall w'')
lst `ifEmpty` x = if null lst then x else lst
distanceToFood d = let (a,b) = w^.snake & turns d & moves & (^.body) & head
(x,y) = w^.food & head
in (a-x)^2 + (b-y)^2
Java
See [[Snake/Java]].
JavaScript
You need the P5 Library to run this code!
const L = 1, R = 2, D = 4, U = 8;
var block = 24, wid = 30, hei = 20, frameR = 7, fruit, snake;
function Snake() {
this.length = 1;
this.alive = true;
this.pos = createVector( 1, 1 );
this.posArray = [];
this.posArray.push( createVector( 1, 1 ) );
this.dir = R;
this.draw = function() {
fill( 130, 190, 0 );
var pos, i = this.posArray.length - 1, l = this.length;
while( true ){
pos = this.posArray[i--];
rect( pos.x * block, pos.y * block, block, block );
if( --l == 0 ) break;
}
}
this.eat = function( frut ) {
var b = this.pos.x == frut.x && this.pos.y == frut.y;
if( b ) this.length++;
return b;
}
this.overlap = function() {
var len = this.posArray.length - 1;
for( var i = len; i > len - this.length; i-- ) {
tp = this.posArray[i];
if( tp.x === this.pos.x && tp.y === this.pos.y ) return true;
}
return false;
}
this.update = function() {
if( !this.alive ) return;
switch( this.dir ) {
case L:
this.pos.x--; if( this.pos.x < 1 ) this.pos.x = wid - 2;
break;
case R:
this.pos.x++; if( this.pos.x > wid - 2 ) this.pos.x = 1;
break;
case U:
this.pos.y--; if( this.pos.y < 1 ) this.pos.y = hei - 2;
break;
case D:
this.pos.y++; if( this.pos.y > hei - 2 ) this.pos.y = 1;
break;
}
if( this.overlap() ) { this.alive = false; } else {
this.posArray.push( createVector( this.pos.x, this.pos.y ) );
if( this.posArray.length > 5000 ) { this.posArray.splice( 0, 1 ); }
}
}
}
function Fruit() {
this.fruitTime = true;
this.pos = createVector();
this.draw = function() {
fill( 200, 50, 20 );
rect( this.pos.x * block, this.pos.y * block, block, block );
}
this.setFruit = function() {
this.pos.x = floor( random( 1, wid - 1 ) );
this.pos.y = floor( random( 1, hei - 1 ) );
this.fruitTime = false;
}
}
function setup() {
createCanvas( block * wid, block * hei );
noStroke(); frameRate( frameR );
snake = new Snake();fruit = new Fruit();
}
function keyPressed() {
switch( keyCode ) {
case LEFT_ARROW: snake.dir = L; break;
case RIGHT_ARROW: snake.dir = R; break;
case UP_ARROW: snake.dir = U; break;
case DOWN_ARROW: snake.dir = D;
}
}
function draw() {
background( color( 0, 0x22, 0 ) );
fill( 20, 50, 120 );
for( var i = 0; i < wid; i++ ) {
rect( i * block, 0, block, block );
rect( i * block, height - block, block, block );
}
for( var i = 1; i < hei - 1; i++ ) {
rect( 1, i * block, block, block );
rect( width - block, i * block, block, block );
}
if( fruit.fruitTime ) {
fruit.setFruit();
frameR += .2;
frameRate( frameR );
}
fruit.draw();
snake.update();
if( snake.eat( fruit.pos ) ) {
fruit.fruitTime = true;
}
snake.draw();
fill( 200 );
textStyle( BOLD ); textAlign( RIGHT ); textSize( 120 );
text( ""+( snake.length - 1 ), 690, 440 );
if( !snake.alive ) text( "THE END", 630, 250 );
}
Kotlin
{{trans|C++}} {{works with|Windows 10}}
// Kotlin Native v0.5
import kotlinx.cinterop.*
import platform.posix.*
import platform.windows.*
const val WID = 60
const val HEI = 30
const val MAX_LEN = 600
const val NUL = '\u0000'
enum class Dir { NORTH, EAST, SOUTH, WEST }
class Snake {
val console: HANDLE
var alive = false
val brd = CharArray(WID * HEI)
var dir = Dir.NORTH
val snk = nativeHeap.allocArray<COORD>(MAX_LEN)
lateinit var head: COORD
var tailIdx = 0
var headIdx = 0
var points = 0
init {
console = GetStdHandle(STD_OUTPUT_HANDLE)!!
SetConsoleTitleW("Snake")
memScoped {
val coord = alloc<COORD>().apply { X = (WID + 1).toShort(); Y = (HEI + 2).toShort() }
SetConsoleScreenBufferSize(console, coord.readValue())
val rc = alloc<SMALL_RECT>().apply {
Left = 0; Top = 0; Right = WID.toShort(); Bottom = (HEI + 1).toShort()
}
SetConsoleWindowInfo(console, TRUE, rc.ptr)
val ci = alloc<CONSOLE_CURSOR_INFO>().apply { dwSize = 1; bVisible = FALSE }
SetConsoleCursorInfo(console, ci.ptr)
}
}
fun play() {
while (true) {
createfield()
alive = true
while (alive) {
drawfield()
readKey()
moveSnake()
Sleep(50)
}
memScoped {
val c = alloc<COORD>().apply { X = 0; Y = (HEI + 1).toShort() }
SetConsoleCursorPosition(console, c.readValue())
}
SetConsoleTextAttribute(console, 0x000b)
print("Play again [Y/N]? ")
val a = readLine()!!.toLowerCase()
if (a.length > 0 && a[0] != 'y') {
nativeHeap.free(snk)
return
}
}
}
private fun createfield() {
memScoped {
val coord = alloc<COORD>().apply { X = 0; Y = 0 }
val c = alloc<DWORDVar>()
FillConsoleOutputCharacterW(console, 32, (HEI + 2) * 80, coord.readValue(), c.ptr)
FillConsoleOutputAttribute(console, 0x0000, (HEI + 2) * 80, coord.readValue(), c.ptr)
SetConsoleCursorPosition(console, coord.readValue())
}
for (x in 0 until WID * HEI) brd[x] = NUL
for (x in 0 until WID) {
brd[x + WID * (HEI - 1)] = '+'
brd[x] = '+'
}
for (y in 1 until HEI) {
brd[WID - 1 + WID * y] = '+'
brd[WID * y] = '+'
}
var xx: Int
var yy: Int
do {
xx = rand() % WID
yy = rand() % (HEI shr 1) + (HEI shr 1)
}
while (brd[xx + WID * yy] != NUL)
brd[xx + WID * yy] = '@'
tailIdx = 0
headIdx = 4
xx = 3
yy = 2
for (cc in tailIdx until headIdx) {
brd[xx + WID * yy] = '#'
snk[cc].X = (3 + cc).toShort()
snk[cc].Y = 2
}
head = snk[3]
dir = Dir.EAST
points = 0
}
private fun readKey() {
if ((GetAsyncKeyState(39).toInt() and 0x8000) != 0) dir = Dir.EAST
if ((GetAsyncKeyState(37).toInt() and 0x8000) != 0) dir = Dir.WEST
if ((GetAsyncKeyState(38).toInt() and 0x8000) != 0) dir = Dir.NORTH
if ((GetAsyncKeyState(40).toInt() and 0x8000) != 0) dir = Dir.SOUTH
}
private fun drawfield() {
memScoped {
val coord = alloc<COORD>()
var t = NUL
for (y in 0 until HEI) {
coord.Y = y.toShort()
for (x in 0 until WID) {
t = brd[x + WID * y]
if (t == NUL) continue
coord.X = x.toShort()
SetConsoleCursorPosition(console, coord.readValue())
if (coord.X == head.X && coord.Y == head.Y) {
SetConsoleTextAttribute(console, 0x002e)
print('O')
SetConsoleTextAttribute(console, 0x0000)
continue
}
when (t) {
'#' -> SetConsoleTextAttribute(console, 0x002a)
'+' -> SetConsoleTextAttribute(console, 0x0019)
'@' -> SetConsoleTextAttribute(console, 0x004c)
}
print(t)
SetConsoleTextAttribute(console, 0x0000)
}
}
print(t)
SetConsoleTextAttribute(console, 0x0007)
val c = alloc<COORD>().apply { X = 0; Y = HEI.toShort() }
SetConsoleCursorPosition(console, c.readValue())
print("Points: $points")
}
}
private fun moveSnake() {
when (dir) {
Dir.NORTH -> head.Y--
Dir.EAST -> head.X++
Dir.SOUTH -> head.Y++
Dir.WEST -> head.X--
}
val t = brd[head.X + WID * head.Y]
if (t != NUL && t != '@') {
alive = false
return
}
brd[head.X + WID * head.Y] = '#'
snk[headIdx].X = head.X
snk[headIdx].Y = head.Y
if (++headIdx >= MAX_LEN) headIdx = 0
if (t == '@') {
points++
var x: Int
var y: Int
do {
x = rand() % WID
y = rand() % (HEI shr 1) + (HEI shr 1)
}
while (brd[x + WID * y] != NUL)
brd[x + WID * y] = '@'
return
}
SetConsoleCursorPosition(console, snk[tailIdx].readValue())
print(' ')
brd[snk[tailIdx].X + WID * snk[tailIdx].Y] = NUL
if (++tailIdx >= MAX_LEN) tailIdx = 0
}
}
fun main(args: Array<String>) {
srand(time(null).toInt())
Snake().play()
}
{{output}}
Similar to C++ entry
OCaml
{{libheader|OCamlSDL2}}
(* A simple Snake Game *)
open Sdl
let width, height = (640, 480)
type pos = int * int
type game_state = {
pos_snake: pos;
seg_snake: pos list;
dir_snake: [`left | `right | `up | `down];
pos_fruit: pos;
sleep_time: int;
game_over: bool;
}
let red = (255, 0, 0)
let blue = (0, 0, 255)
let green = (0, 255, 0)
let black = (0, 0, 0)
let alpha = 255
let fill_rect renderer (x, y) =
let rect = Rect.make4 x y 20 20 in
Render.fill_rect renderer rect;
;;
let display_game renderer state =
let bg_color, snake_color, fruit_color =
if state.game_over
then (red, black, green)
else (black, blue, red)
in
Render.set_draw_color renderer bg_color alpha;
Render.clear renderer;
Render.set_draw_color renderer fruit_color alpha;
fill_rect renderer state.pos_fruit;
Render.set_draw_color renderer snake_color alpha;
List.iter (fill_rect renderer) state.seg_snake;
Render.render_present renderer;
;;
let proc_events dir_snake = function
| Event.KeyDown { Event.keycode = Keycode.Left } -> `left
| Event.KeyDown { Event.keycode = Keycode.Right } -> `right
| Event.KeyDown { Event.keycode = Keycode.Up } -> `up
| Event.KeyDown { Event.keycode = Keycode.Down } -> `down
| Event.KeyDown { Event.keycode = Keycode.Q }
| Event.KeyDown { Event.keycode = Keycode.Escape }
| Event.Quit _ -> Sdl.quit (); exit 0
| _ -> (dir_snake)
let rec event_loop dir_snake =
match Event.poll_event () with
| None -> (dir_snake)
| Some ev ->
let dir = proc_events dir_snake ev in
event_loop dir
let rec pop = function
| [_] -> []
| hd :: tl -> hd :: (pop tl)
| [] -> invalid_arg "pop"
let rec new_pos_fruit seg_snake =
let new_pos =
(20 * Random.int 32,
20 * Random.int 24)
in
if List.mem new_pos seg_snake
then new_pos_fruit seg_snake
else (new_pos)
let update_state req_dir ({
pos_snake;
seg_snake;
pos_fruit;
dir_snake;
sleep_time;
game_over;
} as state) =
if game_over then state else
let dir_snake =
match dir_snake, req_dir with
| `left, `right -> dir_snake
| `right, `left -> dir_snake
| `up, `down -> dir_snake
| `down, `up -> dir_snake
| _ -> req_dir
in
let pos_snake =
let x, y = pos_snake in
match dir_snake with
| `left -> (x - 20, y)
| `right -> (x + 20, y)
| `up -> (x, y - 20)
| `down -> (x, y + 20)
in
let game_over =
let x, y = pos_snake in
List.mem pos_snake seg_snake
|| x < 0 || y < 0
|| x >= width
|| y >= height
in
let seg_snake = pos_snake :: seg_snake in
let seg_snake, pos_fruit, sleep_time =
if pos_snake = pos_fruit
then (seg_snake, new_pos_fruit seg_snake, sleep_time - 1)
else (pop seg_snake, pos_fruit, sleep_time)
in
{ pos_snake;
seg_snake;
pos_fruit;
dir_snake;
sleep_time;
game_over;
}
let () =
Random.self_init ();
Sdl.init [`VIDEO];
let window, renderer =
Render.create_window_and_renderer ~width ~height ~flags:[]
in
Window.set_title ~window ~title:"Snake OCaml-SDL2";
let initial_state = {
pos_snake = (100, 100);
seg_snake = [
(100, 100);
( 80, 100);
( 60, 100);
];
pos_fruit = (200, 200);
dir_snake = `right;
sleep_time = 120;
game_over = false;
} in
let rec main_loop state =
let req_dir = event_loop state.dir_snake in
let state = update_state req_dir state in
display_game renderer state;
Timer.delay state.sleep_time;
main_loop state
in
main_loop initial_state
Perl
[[File:Snake_game_perl.png|200px|thumb|right]]
use utf8;
use Time::HiRes qw(sleep);
use Term::ANSIColor qw(colored);
use Term::ReadKey qw(ReadMode ReadLine);
binmode(STDOUT, ':utf8');
use constant {
VOID => 0,
HEAD => 1,
BODY => 2,
TAIL => 3,
FOOD => 4,
};
use constant {
LEFT => [+0, -1],
RIGHT => [+0, +1],
UP => [-1, +0],
DOWN => [+1, +0],
};
use constant {
BG_COLOR => "on_black",
SLEEP_SEC => 0.05,
};
use constant {
SNAKE_COLOR => ('bold green' . ' ' . BG_COLOR),
FOOD_COLOR => ('red' . ' ' . BG_COLOR),
};
use constant {
U_HEAD => colored('▲', SNAKE_COLOR),
D_HEAD => colored('▼', SNAKE_COLOR),
L_HEAD => colored('◀', SNAKE_COLOR),
R_HEAD => colored('▶', SNAKE_COLOR),
U_BODY => colored('╹', SNAKE_COLOR),
D_BODY => colored('╻', SNAKE_COLOR),
L_BODY => colored('╴', SNAKE_COLOR),
R_BODY => colored('╶', SNAKE_COLOR),
U_TAIL => colored('╽', SNAKE_COLOR),
D_TAIL => colored('╿', SNAKE_COLOR),
L_TAIL => colored('╼', SNAKE_COLOR),
R_TAIL => colored('╾', SNAKE_COLOR),
A_VOID => colored(' ', BG_COLOR),
A_FOOD => colored('❇', FOOD_COLOR),
};
local $| = 1;
my $w = eval { `tput cols` } || 80;
my $h = eval { `tput lines` } || 24;
my $r = "\033[H";
my @grid = map {
[map { [VOID] } 1 .. $w]
} 1 .. $h;
my $dir = LEFT;
my @head_pos = ($h / 2, $w / 2);
my @tail_pos = ($head_pos[0], $head_pos[1] + 1);
$grid[$head_pos[0]][$head_pos[1]] = [HEAD, $dir]; # head
$grid[$tail_pos[0]][$tail_pos[1]] = [TAIL, $dir]; # tail
sub create_food {
my ($food_x, $food_y);
do {
$food_x = rand($w);
$food_y = rand($h);
} while ($grid[$food_y][$food_x][0] != VOID);
$grid[$food_y][$food_x][0] = FOOD;
}
create_food();
sub display {
my $i = 0;
print $r, join("\n",
map {
join("",
map {
my $t = $_->[0];
if ($t != FOOD and $t != VOID) {
my $p = $_->[1];
$i =
$p eq UP ? 0
: $p eq DOWN ? 1
: $p eq LEFT ? 2
: 3;
}
$t == HEAD ? (U_HEAD, D_HEAD, L_HEAD, R_HEAD)[$i]
: $t == BODY ? (U_BODY, D_BODY, L_BODY, R_BODY)[$i]
: $t == TAIL ? (U_TAIL, D_TAIL, L_TAIL, R_TAIL)[$i]
: $t == FOOD ? (A_FOOD)
: (A_VOID);
} @{$_}
)
} @grid
);
}
sub move {
my $grew = 0;
# Move the head
{
my ($y, $x) = @head_pos;
my $new_y = ($y + $dir->[0]) % $h;
my $new_x = ($x + $dir->[1]) % $w;
my $cell = $grid[$new_y][$new_x];
my $t = $cell->[0];
if ($t == BODY or $t == TAIL) {
die "Game over!\n";
}
elsif ($t == FOOD) {
create_food();
$grew = 1;
}
# Create a new head
$grid[$new_y][$new_x] = [HEAD, $dir];
# Replace the current head with body
$grid[$y][$x] = [BODY, $dir];
# Save the position of the head
@head_pos = ($new_y, $new_x);
}
# Move the tail
if (not $grew) {
my ($y, $x) = @tail_pos;
my $pos = $grid[$y][$x][1];
my $new_y = ($y + $pos->[0]) % $h;
my $new_x = ($x + $pos->[1]) % $w;
$grid[$y][$x][0] = VOID; # erase the current tail
$grid[$new_y][$new_x][0] = TAIL; # create a new tail
# Save the position of the tail
@tail_pos = ($new_y, $new_x);
}
}
ReadMode(3);
while (1) {
my $key;
until (defined($key = ReadLine(-1))) {
move();
display();
sleep(SLEEP_SEC);
}
if ($key eq "\e[A" and $dir ne DOWN ) { $dir = UP }
elsif ($key eq "\e[B" and $dir ne UP ) { $dir = DOWN }
elsif ($key eq "\e[C" and $dir ne LEFT ) { $dir = RIGHT }
elsif ($key eq "\e[D" and $dir ne RIGHT) { $dir = LEFT }
}
Perl 6
{{works with|Rakudo|2016.08}} This is a variation of a demo script included in the examples folder for the Perl 6 SDL2::Raw library bindings.
use SDL2::Raw;
use Cairo;
constant W = 1280;
constant H = 960;
constant FIELDW = W div 32;
constant FIELDH = H div 32;
SDL_Init(VIDEO);
my $window = SDL_CreateWindow(
'Snake',
SDL_WINDOWPOS_CENTERED_MASK,
SDL_WINDOWPOS_CENTERED_MASK,
W, H,
OPENGL
);
my $render = SDL_CreateRenderer($window, -1, ACCELERATED +| PRESENTVSYNC);
my $snake_image = Cairo::Image.record(
-> $_ {
.save;
.rectangle: 0, 0, 64, 64;
.clip;
.rgb: 0, 1, 0;
.rectangle: 0, 0, 64, 64;
.fill :preserve;
.rgb: 0, 0, 0;
.stroke;
.restore;
.save;
.translate: 64, 0;
.rectangle: 0, 0, 64, 64;
.clip;
.rgb: 1, 0, 0;
.arc: 32, 32, 30, 0, 2 * pi;
.fill :preserve;
.rgb: 0, 0, 0;
.stroke;
.restore;
}, 128, 128, Cairo::FORMAT_ARGB32);
my $snake_texture = SDL_CreateTexture(
$render,
%PIXELFORMAT<ARGB8888>,
STATIC,
128,
128
);
SDL_UpdateTexture(
$snake_texture,
SDL_Rect.new(
:x(0),
:y(0),
:w(128),
:h(128)
),
$snake_image.data,
$snake_image.stride // 128 * 4
);
SDL_SetTextureBlendMode($snake_texture, 1);
SDL_SetRenderDrawBlendMode($render, 1);
my $snakepiece_srcrect = SDL_Rect.new(:w(64), :h(64));
my $nompiece_srcrect = SDL_Rect.new(:w(64), :h(64), :x(64));
my $event = SDL_Event.new;
enum GAME_KEYS (
K_UP => 82,
K_DOWN => 81,
K_LEFT => 80,
K_RIGHT => 79,
);
my Complex @snakepieces = 10+10i;
my Complex @noms;
my Complex $snakedir = 1+0i;
my $nomspawn = 0;
my $snakespeed = 0.1;
my $snakestep = 0;
my $nom = 4;
my $last_frame_start = now;
main: loop {
my $start = now;
my $dt = $start - $last_frame_start // 0.00001;
while SDL_PollEvent($event) {
my $casted_event = SDL_CastEvent($event);
given $casted_event {
when *.type == QUIT { last main }
when *.type == KEYDOWN {
if GAME_KEYS(.scancode) -> $comm {
given $comm {
when 'K_LEFT' { $snakedir = -1+0i unless $snakedir == 1+0i }
when 'K_RIGHT' { $snakedir = 1+0i unless $snakedir == -1+0i }
when 'K_UP' { $snakedir = 0-1i unless $snakedir == 0+1i }
when 'K_DOWN' { $snakedir = 0+1i unless $snakedir == 0-1i }
}
}
}
}
}
if ($nomspawn -= $dt) < 0 {
$nomspawn += 1;
@noms.push: (^FIELDW).pick + (^FIELDH).pick * i unless @noms > 3;
@noms.pop if @noms[*-1] == any(@snakepieces);
}
if ($snakestep -= $dt) < 0 {
$snakestep += $snakespeed;
@snakepieces.unshift: do given @snakepieces[0] {
($_.re + $snakedir.re) % FIELDW
+ (($_.im + $snakedir.im) % FIELDH) * i
}
if @snakepieces[2..*].first( * == @snakepieces[0], :k ) -> $idx {
@snakepieces = @snakepieces[0..($idx + 1)];
}
@noms .= grep(
{ $^piece == @snakepieces[0] ?? ($nom += 1) && False !! True }
);
if $nom == 0 {
@snakepieces.pop;
} else {
$nom = $nom - 1;
}
}
for @snakepieces {
SDL_SetTextureColorMod(
$snake_texture,
255,
(cos((++$) / 2) * 100 + 155).round,
255
);
SDL_RenderCopy(
$render,
$snake_texture,
$snakepiece_srcrect,
SDL_Rect.new(.re * 32, .im * 32, 32, 32)
);
}
SDL_SetTextureColorMod($snake_texture, 255, 255, 255);
for @noms {
SDL_RenderCopy(
$render,
$snake_texture,
$nompiece_srcrect,
SDL_Rect.new(.re * 32, .im * 32, 32, 32)
)
}
SDL_RenderPresent($render);
SDL_SetRenderDrawColor($render, 0, 0, 0, 0);
SDL_RenderClear($render);
$last_frame_start = $start;
sleep(1 / 50);
}
SDL_Quit();
Phix
{{trans|C++}}
constant W = 60, H = 30, MAX_LEN = 600
enum NORTH, EAST, SOUTH, WEST
sequence board, snake
bool alive
integer tailIdx, headIdx, hdX, hdY, d, points
procedure createField()
clear_screen()
board = repeat("+"&repeat(' ',W-2)&'+',H)
for x=1 to W do
board[1,x] = '+'
end for
board[H] = board[1]
board[1+rand(H-2),1+rand(W-2)] = '@';
snake = repeat(0,MAX_LEN)
board[3,4] = '#'; tailIdx = 1; headIdx = 5;
for c=tailIdx to headIdx do
snake[c] = {3,3+c}
end for
{hdY,hdX} = snake[headIdx-1]; d = EAST; points = 0;
end procedure
procedure drawField()
for y=1 to H do
for x=1 to W do
integer t = board[y,x]
if t!=' ' then
position(y,x)
if x=hdX and y=hdY then
text_color(14); puts(1,'O');
else
text_color({10,9,12}[find(t,"#+@")]); puts(1,t);
end if
end if
end for
end for
position(H+1,1); text_color(7); printf(1,"Points: %d",points)
end procedure
procedure readKey()
integer k = find(get_key(),{333,331,328,336})
if k then d = {EAST,WEST,NORTH,SOUTH}[k] end if
end procedure
procedure moveSnake()
integer x,y
switch d do
case NORTH: hdY -= 1
case EAST: hdX += 1
case SOUTH: hdY += 1
case WEST: hdX -= 1
end switch
integer t = board[hdY,hdX];
if t!=' ' and t!='@' then alive = false; return; end if
board[hdY,hdX] = '#'; snake[headIdx] = {hdY,hdX};
headIdx += 1; if headIdx>MAX_LEN then headIdx = 1 end if
if t=='@' then
points += 1
while 1 do
x = 1+rand(W-2); y = 1+rand(H-2);
if board[y,x]=' ' then
board[y,x] = '@'
return
end if
end while
end if
{y,x} = snake[tailIdx]; position(y,x); puts(1,' '); board[y,x] = ' ';
tailIdx += 1; if tailIdx>MAX_LEN then tailIdx = 1 end if
end procedure
procedure play()
while true do
createField(); alive = true; cursor(NO_CURSOR)
while alive do drawField(); readKey(); moveSnake(); sleep(0.05) end while
cursor(BLOCK_CURSOR); position(H+2,1); bk_color(0); text_color(11);
puts(1,"Play again [Y/N]? ")
if upper(wait_key())!='Y' then return end if
end while
end procedure
play()
Sidef
class SnakeGame(w, h) {
const readkey = frequire('Term::ReadKey')
const ansi = frequire('Term::ANSIColor')
enum (VOID, HEAD, BODY, TAIL, FOOD)
define (
LEFT = [+0, -1],
RIGHT = [+0, +1],
UP = [-1, +0],
DOWN = [+1, +0],
)
define BG_COLOR = "on_black"
define FOOD_COLOR = ("red" + " " + BG_COLOR)
define SNAKE_COLOR = ("bold green" + " " + BG_COLOR)
define SLEEP_SEC = 0.02
const (
A_VOID = ansi.colored(' ', BG_COLOR),
A_FOOD = ansi.colored('❇', FOOD_COLOR),
A_BLOCK = ansi.colored('■', SNAKE_COLOR),
)
has dir = LEFT
has grid = [[]]
has head_pos = [0, 0]
has tail_pos = [0, 0]
method init {
grid = h.of { w.of { [VOID] } }
head_pos = [h//2, w//2]
tail_pos = [head_pos[0], head_pos[1]+1]
grid[head_pos[0]][head_pos[1]] = [HEAD, dir] # head
grid[tail_pos[0]][tail_pos[1]] = [TAIL, dir] # tail
self.make_food()
}
method make_food {
var (food_x, food_y)
do {
food_x = w.rand.int
food_y = h.rand.int
} while (grid[food_y][food_x][0] != VOID)
grid[food_y][food_x][0] = FOOD
}
method display {
print("\033[H", grid.map { |row|
row.map { |cell|
given (cell[0]) {
when (VOID) { A_VOID }
when (FOOD) { A_FOOD }
default { A_BLOCK }
}
}.join('')
}.join("\n")
)
}
method move {
var grew = false
# Move the head
var (y, x) = head_pos...
var new_y = (y+dir[0] % h)
var new_x = (x+dir[1] % w)
var cell = grid[new_y][new_x]
given (cell[0]) {
when (BODY) { die "\nYou just bit your own body!\n" }
when (TAIL) { die "\nYou just bit your own tail!\n" }
when (FOOD) { grew = true; self.make_food() }
}
# Create a new head
grid[new_y][new_x] = [HEAD, dir]
# Replace the current head with body
grid[y][x] = [BODY, dir]
# Update the head position
head_pos = [new_y, new_x]
# Move the tail
if (!grew) {
var (y, x) = tail_pos...
var pos = grid[y][x][1]
var new_y = (y+pos[0] % h)
var new_x = (x+pos[1] % w)
grid[y][x][0] = VOID # erase the current tail
grid[new_y][new_x][0] = TAIL # create a new tail
tail_pos = [new_y, new_x]
}
}
method play {
STDOUT.autoflush(true)
readkey.ReadMode(3)
try {
loop {
var key
while (!defined(key = readkey.ReadLine(-1))) {
self.move()
self.display()
Sys.sleep(SLEEP_SEC)
}
given (key) {
when ("\e[A") { if (dir != DOWN ) { dir = UP } }
when ("\e[B") { if (dir != UP ) { dir = DOWN } }
when ("\e[C") { if (dir != LEFT ) { dir = RIGHT } }
when ("\e[D") { if (dir != RIGHT) { dir = LEFT } }
}
}
}
catch {
readkey.ReadMode(0)
}
}
}
var w = `tput cols`.to_i
var h = `tput lines`.to_i
SnakeGame(w || 80, h || 24).play