Hacktoberfest2020/snake_game_using_java_script at main · David241-webdeveloper/Hacktoberfest2020 · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
<canvas id="gc" width="400" height="400"></canvas>

<script>

window.onload=function() {

    canv=document.getElementById("gc");

    ctx=canv.getContext("2d");

    document.addEventListener("keydown",keyPush);

    setInterval(game,1000/15);

}

px=py=10;

gs=tc=20;

ax=ay=15;

xv=yv=0;

trail=[];

tail = 5;

function game() {

    px+=xv;

    py+=yv;

    if(px<0) {

        px= tc-1;

    }

    if(px>tc-1) {

        px= 0;

    }

    if(py<0) {

        py= tc-1;

    }

    if(py>tc-1) {

        py= 0;

    }

    ctx.fillStyle="black";

    ctx.fillRect(0,0,canv.width,canv.height);


    ctx.fillStyle="lime";

    for(var i=0;i<trail.length;i++) {

        ctx.fillRect(trail[i].x*gs,trail[i].y*gs,gs-2,gs-2);

        if(trail[i].x==px && trail[i].y==py) {

            tail = 5;

        }

    }

    trail.push({x:px,y:py});

    while(trail.length>tail) {

    trail.shift();

    }


    if(ax==px && ay==py) {

        tail++;

        ax=Math.floor(Math.random()*tc);

        ay=Math.floor(Math.random()*tc);

    }

    ctx.fillStyle="red";

    ctx.fillRect(ax*gs,ay*gs,gs-2,gs-2);

}

function keyPush(evt) {

    switch(evt.keyCode) {

        case 37:

            xv=-1;yv=0;

            break;

        case 38:

            xv=0;yv=-1;

            break;

        case 39:

            xv=1;yv=0;

            break;

        case 40:

            xv=0;yv=1;

            break;

    }

}

</script>