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导语

随着数据中心可视化系统的要求越来越高,2D、3D效果都要求几乎逼真;3D地板,相较于2D,实为更易,只需引擎(如:twaver.js、three.js等),外加一张地板图片,便可实现;本文重点介绍如何使用2D绘制地板、以及如何做出伪3D的地板效果;

先睹为快

2D机房地板

伪3D机房地板

木制地板

若有所思

看到如上效果,你也许会嘲笑鄙人;这样的效果,一张图片就解决,何以兴师动众,大动干戈;然,若您知道,房间地板的形状、材质参差不齐,如何一张图片能解决,你是否理解了我的所作所为,所思所想呢?

这样地板见过吗?

花花世界地板

木板材质

大理石地板

如你所想,这样给出地板材质和坐标信息,便很容易呈现形形状状的地板了,具体是如何实现的呢?

实验天地

Canvas

HTML5的Canvas标签,应该无需赘言, 若您对此不解,请移步Canvas.

"给我一张Canvas,还你你个精彩世界";--世界著名学者Canvas

createPattern

The CanvasRenderingContext2D
.createPattern() method of the Canvas 2D API creates a pattern using the specified image (a CanvasImageSource ). It repeats the source in the directions specified by the repetition argument. This method returns a CanvasPattern .

image

 CanvasImageSource to be used as image to repeat. It can either be a:

  • HTMLImageElement

  • HTMLVideoElement

  • HTMLCanvasElement

  • CanvasRenderingContext2D

  • ImageBitmap

  • Blob

repetition

 DOMString indicating how to repeat the image. Possible values are:

  • "repeat" (both directions),

  • "repeat-x" (horizontal only),

  • "repeat-y" (vertical only), or

  • "no-repeat" (neither).

If repetition is an empty string ('') or null (but not undefined), repetition will be "repeat".

Example

<canvas id="canvas"></canvas>
</pre>
<pre>
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');

var img = new Image();
img.src = 'https://mdn.mozillademos.org/files/222/Canvas_createpattern.png';
img.onload = function() {
  var pattern = ctx.createPattern(img, 'repeat');
  ctx.fillStyle = pattern;
  ctx.fillRect(0, 0, 400, 400);
};

实验结果

是不是非常的简单,正如API所言,可以支持图片、Canvas、Vedio、Blob等等,因此,我们可以在Canvas上自己绘制地板样式,再用于填充,起步完美!

填充Canvas内容

<!DOCTYPE html>
<html>
<head>
    <title></title>
    <script type="text/javascript">
        function init() {
            var canvas = document.getElementById("bg");
            var ctx = canvas.getContext("2d");

            var tile = document.createElement('canvas');
            tile.width = 50;
            tile.height = 50;
            var tileCtx = tile.getContext("2d");
            draw(tileCtx);
            var objPattern = ctx.createPattern(tile, "repeat");
            ctx.rotate(-(Math.PI / 180) * 25);
            ctx.fillStyle = objPattern;
            ctx.fillRect(50, 300,700,400);
        }

        function draw(tileCtx) {
            var translator = new Translator3D({x:0,y:0,width:50,height:50});
            tileCtx.save();
            tileCtx.beginPath();
            tileCtx.strokeStyle = 'rgba(100,100,0,1)';        
            var point  = {x:0,y:25};
            // point = translator.translate(point.x,point.y);
            tileCtx.moveTo(point.x, point.y);
            var point  = {x:50,y:25};
            // point = translator.translate(point.x,point.y);
            tileCtx.lineTo(point.x, point.y);
            var point  = {x:25,y:0};
            // point = translator.translate(point.x,point.y);
            tileCtx.moveTo(point.x, point.y);
            var point  = {x:25,y:50};
            // point = translator.translate(point.x,point.y);
            tileCtx.lineTo(point.x, point.y);
            
            tileCtx.stroke();
            tileCtx.restore();
        }
    </script>
</head>
<body onload="init();">
    <canvas id="bg" width="1000" height="500" ></canvas>
</body>
</html>

刷Canvas内容

写到这,应该是对此技术应该非常熟练了,若想做出开篇的效果图,添加自己的创造,很容易便可实现;

参考资料

[1].HTML5,不只是看上去很美(第二弹:打造最美3D机房)
[2].CanvasRenderingContext2D.createPattern
[3].Canvas


FuJie
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Hello EcmaScript!