canvas - HTML5 Canvas アニメーションは CPU の 88-98% を使用します

Question

偽のピクセル化された世界地図をアニメーション化して、異なる色の間でスムーズに移行しようとしています。私はもともと jquery とテーブルでこれを行いましたが、CPU 使用率が非常に高かったので、代わりに html5 キャンバスを試してみようと思いました。ただし、これでもCPU使用率が非常に高くなります。コード内の大きな配列であるかどうか疑問に思っています（正方形を埋める場所を示すために使用します）。どんな助けでも大歓迎です。

<!DOCTYPE html>
<html>
<head>
    <title>canvas version</title>
    <script src="raphael.js"></script>
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
</head>
<body>
<div id="canvasesdiv" style="position:relative; width:864px; height:456px">
    <canvas id="world-map" width="864" height="456" style="position:absolute; left:0px; top:0px; z-index:1;">
    </canvas>
    <canvas id="backdrop" width="864" height="456" style="position:absolute; left:0px; top:0px; z-index:0;"></canvas>
    <script type="text/javascript">
        //declare vars
        var ctx1
        var ctx2
        var layer1
        var layer2
        var red = 255;
        var dr = 1;
        //initialization
        function init() {
            layer1 = document.getElementById("backdrop");
            ctx1 = layer1.getContext("2d");
            //layer2 = document.getElementById("world-map");
            //ctx2 = layer2.getContext("2d");
            drawMap(red);
            setInterval(function(){red = drawMap(red);},1);
            }

            //LOOP THROUGH THE ARRAY IT SHOULD BE 38 ROWS EACH WITH 72 COLUMN ENTRIES make each one 12x12 and then fill according to array non zero entries
        var array = [[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 21.0, 22.0, 0.0, 0.0, 25.0, 26.0, 27.0, 28.0, 29.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 18.0, 19.0, 20.0, 21.0, 22.0, 23.0, 24.0, 25.0, 26.0, 27.0, 28.0, 29.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 22.0, 23.0, 24.0, 25.0, 26.0, 27.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 0.0, 0.0, 53.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 0.0, 22.0, 23.0, 24.0, 25.0, 26.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 0.0, 0.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 22.0, 23.0, 0.0, 0.0, 0.0, 27.0, 28.0, 0.0, 0.0, 0.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 1.0, 2.0, 0.0, 0.0, 0.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 30.0, 0.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 0.0, 0.0, 0.0, 60.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 0.0, 0.0, 60.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 29.0, 30.0, 0.0, 0.0, 0.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 29.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 0.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 29.0, 30.0, 31.0, 32.0, 0.0, 0.0, 0.0, 0.0, 0.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 58.0, 59.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 7.0, 8.0, 9.0, 0.0, 0.0, 0.0, 13.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 0.0, 39.0, 40.0, 41.0, 42.0, 43.0, 44.0, 45.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 7.0, 8.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 0.0, 39.0, 40.0, 41.0, 42.0, 0.0, 0.0, 0.0, 46.0, 47.0, 48.0, 49.0, 50.0, 51.0, 52.0, 53.0, 54.0, 55.0, 56.0, 57.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 7.0, 8.0, 0.0, 10.0, 11.0, 0.0, 13.0, 14.0, 15.0, 16.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 42.0, 43.0, 0.0, 0.0, 46.0, 47.0, 48.0, 49.0, 0.0, 51.0, 52.0, 53.0, 54.0, 0.0, 0.0, 57.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 8.0, 9.0, 10.0, 11.0, 0.0, 0.0, 0.0, 0.0, 0.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 25.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 0.0, 0.0, 0.0, 0.0, 0.0, 47.0, 48.0, 0.0, 0.0, 51.0, 52.0, 53.0, 54.0, 0.0, 0.0, 57.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 11.0, 0.0, 0.0, 14.0, 0.0, 0.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 47.0, 0.0, 0.0, 0.0, 0.0, 52.0, 53.0, 54.0, 0.0, 0.0, 57.0, 58.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 27.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 48.0, 0.0, 0.0, 0.0, 52.0, 0.0, 0.0, 0.0, 0.0, 57.0, 58.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 28.0, 29.0, 30.0, 31.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 41.0, 0.0, 0.0, 0.0, 0.0, 46.0, 0.0, 0.0, 0.0, 0.0, 0.0, 52.0, 53.0, 0.0, 0.0, 56.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 32.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 40.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 53.0, 0.0, 55.0, 56.0, 57.0, 58.0, 59.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 53.0, 54.0, 55.0, 56.0, 57.0, 0.0, 59.0, 60.0, 61.0, 62.0, 0.0, 64.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 54.0, 55.0, 0.0, 0.0, 0.0, 0.0, 0.0, 61.0, 62.0, 63.0, 64.0, 65.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 22.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 57.0, 58.0, 0.0, 0.0, 0.0, 0.0, 63.0, 64.0, 0.0, 66.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 39.0, 0.0, 41.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 59.0, 60.0, 0.0, 62.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 0.0, 40.0, 41.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 0.0, 0.0, 0.0, 0.0, 67.0, 0.0, 69.0, 0.0, 71.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 21.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 38.0, 0.0, 40.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 63.0, 0.0, 0.0, 66.0, 0.0, 0.0, 0.0, 0.0, 71.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 18.0, 19.0, 20.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 33.0, 34.0, 35.0, 36.0, 37.0, 0.0, 0.0, 40.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 63.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 34.0, 35.0, 36.0, 37.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 63.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 18.0, 19.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 35.0, 36.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 55.0, 56.0, 57.0, 58.0, 59.0, 60.0, 61.0, 62.0, 63.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 18.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 60.0, 61.0, 62.0, 0.0, 0.0, 0.0, 0.0, 67.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 15.0, 16.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 60.0, 61.0, 0.0, 0.0, 0.0, 0.0, 66.0, 67.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 16.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 60.0, 0.0, 0.0, 0.0, 0.0, 65.0, 66.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 16.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 64.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 16.0, 17.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 17.0, 18.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]]//  

            //Draw the map and animate the background in red only for now
        function drawMap(){
            ctx1.clearRect(0,0, 864, 456);
            red -= dr
            if (red < 0 || red > 255){
                dr = -dr
            }
            ctx1.fillStyle = 'rgb('+red+',0,0)';
            ctx1.strokeStyle = '#000';
            for (var row = 0; row < 38; row+=1){
                for (var col = 0; col < 72; col+=1){
                    if (array[row][col] != 0.0){
                        ctx1.fillRect(col*12,row*12,12,12);
                        ctx1.strokeRect(col*12,row*12,12,12);
                    }
                }
            }
            return red;
        }
    init();  
    </script>
    </div>
</body>
</html>

score 8 · Accepted Answer

コードを変更する方法は次のとおりです。主な変更点：

drawMapできるだけ速く呼び出さないでください。代わりに、30 fps で最大にします (実際にはわずかに低くなります)。
ゼロをスキップして xy オフセットを 1 回だけ事前計算します。これにより、でループする反復回数が大幅に短縮されdrawMapます。(~970 対 ~2700)
drawMapクロージャーであるという事実を使用して、redそれを返す/割り当てる必要なしに直接変更します。
のハードコーディングを削除し12、代わりsquareSizeに 1 つの場所で設定して、それに応じてコードとキャンバスを更新できるようにします。
低い fps を考慮する5代わりに、「フレーム」ごとのオフセットをに変更します。1実際には、redPerSecond 変数を指定し、呼び出し間のフレーム間遅延を計算してdrawMap、フレームレートに関係なく同じワールドスピードでカラーパルスが発生するようにするのが最善の選択です。
コードを短くするためにマップ配列からすべての小数を削除し、適切な改行を導入して、テキストエディターが泣かないようにします。
strokeStyleを呼び出すたびにを同じ値に設定する必要はありませんdrawMap()。

  var map = [
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,21,22,0,0,25,26,27,28,29,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,18,19,20,21,22,23,24,25,26,27,28,29,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,12,13,14,15,16,17,18,19,0,0,22,23,24,25,26,27,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,44,45,46,47,48,49,50,0,0,53,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,0,22,23,24,25,26,0,0,0,0,0,0,33,34,35,36,37,0,0,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,0,0,22,23,0,0,0,27,28,0,0,0,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,0,0,0,0,0,0,0,0,0],
    [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,0,0,0,0,0,0,0,0,0,0,0,0,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,0,0,0,0,0,0,0,0,0,0,0],
    [0,1,2,0,0,0,6,7,8,9,10,11,12,13,14,15,16,17,18,19,0,0,0,0,0,0,0,0,0,0,30,0,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,0,0,0,60,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,6,7,8,9,10,11,12,13,14,15,16,17,18,19,0,0,0,0,0,0,0,0,0,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,0,0,60,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,6,7,8,9,10,11,12,13,14,15,16,17,18,19,0,0,0,0,0,0,0,0,0,0,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,5,6,7,8,9,10,11,12,13,14,15,16,17,18,0,0,0,0,0,0,0,0,0,0,0,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,5,6,7,8,9,10,11,12,13,14,15,16,0,0,0,0,0,0,0,0,0,0,0,0,29,30,0,0,0,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,5,6,7,8,9,10,11,12,13,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,29,0,0,0,33,34,35,0,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,5,6,7,8,9,10,11,12,13,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,29,30,31,32,0,0,0,0,0,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,5,6,7,8,9,10,11,12,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,6,7,8,9,0,0,0,13,0,0,0,0,0,0,0,0,0,0,0,0,0,27,28,29,30,31,32,33,34,35,36,37,0,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,6,7,8,0,0,0,12,13,14,0,0,0,0,0,0,0,0,0,0,0,0,27,28,29,30,31,32,33,34,35,36,37,0,39,40,41,42,0,0,0,46,47,48,49,50,51,52,53,54,55,56,57,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,7,8,0,10,11,0,13,14,15,16,0,0,0,0,0,0,0,0,0,0,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,0,0,46,47,48,49,0,51,52,53,54,0,0,57,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,8,9,10,11,0,0,0,0,0,17,0,0,0,0,0,0,0,25,0,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,0,0,0,0,0,47,48,0,0,51,52,53,54,0,0,57,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,11,0,0,14,0,0,17,0,0,0,0,0,0,0,0,0,27,28,29,30,31,32,33,34,35,36,37,38,39,40,0,0,0,0,0,0,47,0,0,0,0,52,53,54,0,0,57,58,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,12,13,14,15,16,17,0,0,0,0,0,0,0,0,0,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,0,0,0,0,0,0,48,0,0,0,52,0,0,0,0,57,58,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,13,14,15,16,17,18,0,0,0,0,0,0,0,0,0,28,29,30,31,32,33,34,35,36,37,38,39,40,41,0,0,0,0,46,0,0,0,0,0,52,53,0,0,56,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,12,13,14,15,16,17,18,0,0,0,0,0,0,0,0,0,0,0,0,0,32,33,34,35,36,37,38,39,40,0,0,0,0,0,0,0,0,0,0,0,0,53,0,55,56,57,58,59,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,12,13,14,15,16,17,18,19,20,0,0,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,39,0,0,0,0,0,0,0,0,0,0,0,0,0,53,54,55,56,57,0,59,60,61,62,0,64,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,12,13,14,15,16,17,18,19,20,21,22,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,54,55,0,0,0,0,0,61,62,63,64,65,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,13,14,15,16,17,18,19,20,21,22,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,39,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,57,58,0,0,0,0,63,64,0,66,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,13,14,15,16,17,18,19,20,21,0,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,39,0,41,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,59,60,0,62,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,14,15,16,17,18,19,20,21,0,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,0,40,41,0,0,0,0,0,0,0,0,0,0,0,0,0,55,56,57,58,59,60,61,62,0,0,0,0,67,0,69,0,71],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,18,19,20,21,0,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,38,0,40,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,56,57,58,59,60,61,62,63,0,0,66,0,0,0,0,71],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,18,19,20,0,0,0,0,0,0,0,0,0,0,0,0,33,34,35,36,37,0,0,40,0,0,0,0,0,0,0,0,0,0,0,0,0,0,55,56,57,58,59,60,61,62,63,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,18,19,0,0,0,0,0,0,0,0,0,0,0,0,0,0,34,35,36,37,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,55,56,57,58,59,60,61,62,63,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,18,19,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,35,36,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,55,56,57,58,59,60,61,62,63,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,18,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,60,61,62,0,0,0,0,67,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,15,16,17,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,60,61,0,0,0,0,66,67,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,16,17,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,60,0,0,0,0,65,66,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,16,17,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,64,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,16,17,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
    [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,17,18,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
  ];
  var squareSize = 12;
  var nonZeroIndices = [];
  var rows = map.length, cols=map[0].length;
  for (var row=0; row<rows; ++row){
    for (var col=0; col<cols; ++col){
      if (map[row][col]) nonZeroIndices.push( [col*squareSize,row*squareSize] );
    }
  }
  var nonZeroes = nonZeroIndices.length;

  window.onload = function(){
    var layer1 = document.getElementById("backdrop");
    var ctx1   = layer1.getContext('2d');
    var red=255, offset=5;
    var w = layer1.width  = map[0].length * squareSize;
    var h = layer1.height = map.length    * squareSize;
    ctx1.strokeStyle = '#000';
    var drawMap = function(){
      ctx1.clearRect(0,0,w,h);
      red -= offset;
      ctx1.fillStyle = 'rgb('+red+',0,0)';
      for (var i=0; i<nonZeroes; ++i){
        var xy = nonZeroIndices[i];
        ctx1.fillRect(xy[0],xy[1],squareSize,squareSize);
        ctx1.strokeRect(xy[0],xy[1],squareSize,squareSize);
      }
      if (red<0 || red>255) offset *= -1;
    };
    setInterval( drawMap, 1000/30 );
  };

<div id="canvasesdiv" style="position:relative; width:864px; height:456px">
  <canvas id="world-map" width="864" height="456" style="position:absolute; left:0px; top:0px; z-index:1;"></canvas>
  <canvas id="backdrop" width="864" height="456" style="position:absolute; left:0px; top:0px; z-index:0;"></canvas>
</div>

score 6 · Accepted Answer

さて、あなたはミリ秒ごとに 38 * 72 = 2736 の四角形の塗りつぶし/ストロークをスケジュールしています (setInterval は秒単位ではなくミリ秒単位で引数を取ります)。つまり、ブラウザーに 1 秒間に 2,736,000 個の四角形を描画させようとしているのです。

これは GPU にとっては大したことではありませんが、ソフトウェアレンダラーにとってはかなりの負荷です。これは、Direct2D などが普及するまで、ほとんどのブラウザーが Canvas 要素に対して持っているものです。

canvas - HTML5 Canvas アニメーションは CPU の 88-98% を使用します

2 に答える 2

Related

Reference