工作中发现，在 ios 做 webgl 不能将 canvas 的大小设置超过 4096*4096，如果超出，ios 将不显示这个 canvas。下面是做的小实验。
当大小为 4096*4096
![pc正常]()
![ios正常]()
当大小为 4096*4097
![pc正常]()
![ios不显示]()
贴上实验代码:
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| <!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
</head>
<body style="background-color: #000">
<script>
var canvas = document.createElement("canvas");
canvas.width = 4096;
canvas.height = 4097;
var context = canvas.getContext("2d");
context.fillStyle = "#fff";
context.fillRect(0, 0, 1024, 1024);
context.fillStyle = "#f00";
context.fillRect(0, 0, 512, 512);
context.fillStyle = "#fff";
context.font = "30px 黑体";
context.fillText(
"当画布大小为:" + canvas.width + "*" + canvas.height,
0,
256
);
document.body.appendChild(canvas);
</script>
</body>
</html>
|
