js生成点阵字体

#wrap{
    position: relative;
    height: 200px;
}
#wrap span{
    position: absolute;
    width: 7px;
    height: 7px;
    border: 1px solid #000;
}

<div id="wrap"></div>
<div>
    <input type="text" id="text" value="哥">
    <button onclick="draw()" id="btn">确定</button>
</div>

var canvas = document.createElement(‘canvas‘);
var ctx = canvas.getContext(‘2d‘);
var cols = 16;
var rows = 16;
function lattice(txt){
    cols = txt.length * 16
    canvas.width = cols;
    canvas.height = rows;
    ctx.clearRect(0,0,cols,rows);
    ctx.font = "16px SimSun";
    ctx.fillStyle = "#000";
    ctx.fillText(txt, 0, 14);
    var data = ctx.getImageData(0, 0, cols, rows)
    var len = data.data.length;
    var res = ‘‘;
    for(var i = 1; i <= rows; i++){
        for(var j = 1; j <= cols; j++){
            var pos = (( i-1 )*cols+( j ))*4 -1;
            if(data.data[pos] > 0){
                res += `<span class="black" style="left: ${j*10}px;top: ${i*10}px"></span>`
            }
        }
    }
    wrap.innerHTML = res;
}
function draw(){
    var txt = text.value;
    if(txt){
        lattice(txt);
    }
}    
draw();