canvas基础—02绘制其他曲线

布满荆棘的人生 2022-03-20 11:12 227阅读 0赞

### 1.绘制其他曲线 ###

### ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70][] ###

**arcTo(x1,y1,x2,y2,r)**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 1][]

<!DOCTYPE html>
    <html>
    <head> 
    <meta charset="utf-8"> 
    <title>canvas学习</title>
    <style>
    body{background: black}
    #c1{background: white}
    span{color: white}
    </style> 
    <script type="text/javascript">
        window.onload = function(){
            var oC = document.getElementById('c1');
            var oGC = oC.getContext('2d');
            oGC.moveTo(100,200)
            oGC.arcTo(100,100,200,100,50)
            oGC.stroke()
        }
    
    </script>
    </head>
    <body>
    
    <canvas id="c1" width="400" height="400">
    	<span>不支持canvas浏览器</span>
    </canvas>
    
    </body>
    </html>

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 2][]

**贝塞尔曲线quadraticCurveTo(第一组控制点，第二组结束坐标)**

<!DOCTYPE html>
    <html>
    <head> 
    <meta charset="utf-8"> 
    <title>canvas学习</title>
    <style>
    body{background: black}
    #c1{background: white}
    span{color: white}
    </style> 
    <script type="text/javascript">
        window.onload = function(){
            var oC = document.getElementById('c1');
            var oGC = oC.getContext('2d');
            
            oGC.moveTo(100,200)//初始点
            // quadraticCurveTo(第一组控制点，第二组控制点)
            oGC.quadraticCurveTo(100,100,200,100)
            oGC.stroke()
        }
    
    </script>
    </head>
    <body>
    
    <canvas id="c1" width="400" height="400">
    	<span>不支持canvas浏览器</span>
    </canvas>
    
    </body>
    </html>

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 3][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 4][]

**bezierCurveTo（不做介绍）**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 5][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70]: /images/20220320/32af160f9ee5452cbed2ad838689d146.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 1]: /images/20220320/de85a5cccf4f408cba91622b9942d29a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 2]: /images/20220320/b502bad739084059ada1cfbfe3a17670.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 3]: /images/20220320/92107b2933084d3398e914df0a8b69ee.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 4]: /images/20220320/1f236eea2a7146afb2482037574c3f0c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2ppYW9qc3Vu_size_16_color_FFFFFF_t_70 5]: /images/20220320/acd74bce5d2b465fb779c2d275e413eb.png