HTML5 Canvas如何實(shí)現(xiàn)紋理填充與描邊(Fill And Stroke)

字號:


    本文為大家詳細(xì)介紹下HTML5 Canvas Fill 與Stroke文字效果,基于Canvas如何實(shí)現(xiàn)紋理填充與描邊、顏色填充與描邊,具體代碼如下,感興趣的朋友可以參考下哈,希望對大家有所幫助
    演示HTML5 Canvas Fill 與Stroke文字效果,基于Canvas如何實(shí)現(xiàn)紋理填充與描邊。
    一:顏色填充與描邊
    顏色填充可以通過fillStyle來實(shí)現(xiàn),描邊顏色可以通過strokeStyle來實(shí)現(xiàn)。簡單示例
    如下:
    代碼如下:
    // fill and stroke text
    ctx.font = '60pt Calibri';
    ctx.lineWidth = 3;
    ctx.strokeStyle = 'green';
    ctx.strokeText('Hello World!', 20, 100);
    ctx.fillStyle = 'red';
    ctx.fillText('Hello World!', 20, 100);
    二:紋理填充與描邊
    HTML5 Canvas還支持紋理填充,通過加載一張紋理圖像,然后創(chuàng)建畫筆模式,創(chuàng)建紋理模式的API為ctx.createPattern(imageTexture,"repeat");第二參數(shù)支持四個(gè)值,分別為”repeat-x”, ”repeat-y”, ”repeat”,”no-repeat”意思是紋理分別沿著X軸,Y軸,XY方向沿重復(fù)或者不重復(fù)。紋理描邊與填充的代碼如下:
    代碼如下:
    var woodfill = ctx.createPattern(imageTexture,"repeat");
    ctx.strokeStyle = woodfill;
    ctx.strokeText('Hello World!', 20, 200);
    // fill rectangle
    ctx.fillStyle = woodfill;
    ctx.fillRect(60, 240, 260, 440);
    紋理圖片:
    名單
    代碼:
    代碼如下:
    <!DOCTYPE html>
    <html>
    <head>
    <meta http-equiv="X-UA-Compatible" content="chrome=IE8">
    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
    <title>Canvas Fill And Stroke Text Demo</title>
    <link href="default.css" rel="stylesheet" />
    <script>
    var ctx = null; // global variable 2d context
    var imageTexture = null;
    window.onload = function() {
    var canvas = document.getElementById("text_canvas");
    console.log(canvas.parentNode.clientWidth);
    canvas.width = canvas.parentNode.clientWidth;
    canvas.height = canvas.parentNode.clientHeight;
    if (!canvas.getContext) {
    console.log("Canvas not supported. Please install a HTML5 compatible browser.");
    return;
    }
    // get 2D context of canvas and draw rectangel
    ctx = canvas.getContext("2d");
    ctx.fillStyle="black";
    ctx.fillRect(0, 0, canvas.width, canvas.height);
    // fill and stroke text
    ctx.font = '60pt Calibri';
    ctx.lineWidth = 3;
    ctx.strokeStyle = 'green';
    ctx.strokeText('Hello World!', 20, 100);
    ctx.fillStyle = 'red';
    ctx.fillText('Hello World!', 20, 100);
    // fill and stroke by pattern
    imageTexture = document.createElement('img');
    imageTexture.src = "../pattern.png";
    imageTexture.onload = loaded();
    }
    function loaded() {
    // delay to image loaded
    setTimeout(textureFill, 1000/30);
    }
    function textureFill() {
    // var woodfill = ctx.createPattern(imageTexture, "repeat-x");
    // var woodfill = ctx.createPattern(imageTexture, "repeat-y");
    // var woodfill = ctx.createPattern(imageTexture, "no-repeat");
    var woodfill = ctx.createPattern(imageTexture, "repeat");
    ctx.strokeStyle = woodfill;
    ctx.strokeText('Hello World!', 20, 200);
    // fill rectangle
    ctx.fillStyle = woodfill;
    ctx.fillRect(60, 240, 260, 440);
    }
    </script>
    </head>
    <body>
    <h1>HTML5 Canvas Text Demo - By Gloomy Fish</h1>
    <pre>Fill And Stroke</pre>
    <div id="my_painter">
    <canvas id="text_canvas"></canvas>
    </div>
    </body>
    </html>