/examples/Snake/game.d

  1import djehuty;
  2
  3import io.console;
  4import math.random;
  5
  6import constants;
  7import posn;
  8import snake;
  9import win;
 10
 11enum DeathBy {
 12	NotDead,
 13	CollisionSelf,
 14	CollisionPortal,
 15	CollisionReverse,
 16	Quit,
 17}
 18
 19class SnakeGame {
 20	this(SnakeWindow win_n) {
 21		_win = win_n;
 22
 23		_max_x = _win.width - 1;
 24		_max_y = _win.height - 1;
 25
 26		_rand = new Random();
 27
 28		Dir d = cast(Dir)_rand.choose([Dir.Up, Dir.Down, Dir.Left, Dir.Right]);
 29		_snake = new Snake(_max_x, _max_y, d);
 30	}
 31
 32	void turn(Dir d) {
 33		if (_snake.direction == -d) {
 34			_snake.reverse();
 35			_rev = true;
 36		}
 37		_snake.direction = d;
 38	}
 39
 40	Snake snake() {
 41		return _snake.dup;
 42	}
 43
 44	void frame() {
 45		if (_snake is null || _win is null)
 46			return;
 47
 48		Posn oldTail = _snake.tail.dup;
 49
 50		MoveResult move = _snake.slither();
 51
 52		if (_snake.length > 1) {
 53			drawTile(_snake.neck, Tile.Block, TileColor.Block);
 54		}
 55
 56		if (_snake.length <= 1 || _snake.tail != oldTail) {
 57			drawTile(oldTail, Tile.Void);
 58		}
 59
 60		drawTile(_snake.head, Tile.Head, TileColor.Head);
 61
 62		if (move == MoveResult.CollisionSelf) {
 63			if (_rev) {
 64				_win.gameOver(DeathBy.CollisionReverse);
 65			} else {
 66				_win.gameOver(DeathBy.CollisionSelf);
 67			}
 68			return;
 69		} else if (_portal !is null && _portal == _snake.head) {
 70			_win.gameOver(DeathBy.CollisionPortal);
 71			return;
 72		} else if (_food !is null && _food == _snake.head) {
 73			_snake.head.moveTo(_portal);
 74
 75			drawTile(_food, Tile.Void);
 76
 77			_food = null;
 78			_portal = null;
 79
 80			_snake.elongate(cast(uint)_rand.next(Growth.Min, Growth.Max));
 81		}
 82
 83		if (_food is null) {
 84			_food = positionItem();
 85			drawTile(_food, Tile.Food, TileColor.Food);
 86		}
 87		if (_portal is null) {
 88			_portal = positionItem();
 89			drawTile(_portal, Tile.Portal, TileColor.Portal);
 90		}
 91
 92		_rev = false;
 93
 94		_win.setSpeed();
 95	}
 96
 97private:
 98	void drawTile(Posn p, Tile t) {
 99		Console.position(p.x, p.y);
100		Console.putChar(t);
101	}
102
103	void drawTile(Posn p, Tile t, TileColor c) {
104		Console.setColor(c);
105		drawTile(p, t);
106	}
107
108	Posn positionItem() {
109		Posn ret;
110		while (ret is null) {
111			auto r = new Posn(cast(uint)_rand.next(_max_x + 1), cast(uint)_rand.next(_max_y + 1));
112			if (_snake !is null && _snake == r)
113				continue;
114			if (_food !is null && _food == r)
115				continue;
116			if (_portal !is null && _portal == r)
117				continue;
118			ret = r;
119		}
120		return ret;
121	}
122
123	uint _max_x, _max_y;
124
125	bool _rev;
126
127	SnakeWindow _win;
128	Random _rand;
129
130	Snake _snake;
131	Posn _food, _portal;
132}
133