如何使用php的gd库画一条抗锯齿的粗斜线?
如题，使用多边形画的填充图是有锯齿的。imageantialias函数是无效的。
------解决方案--------------------
点阵图有锯齿是必然的
imageantialias 的抗锯齿是有作用的，你可以对比他打开和关闭时的效果
如果你对 imageantialias 的效果不满意（毕竟GD不是专业的图像处理包），那就要你自己编程解决了
------解决方案--------------------
他是扰码加密的，有空研究一下
------解决方案--------------------
好无聊啊，最终是用 js 实现的
------解决方案--------------------
JS有现成的插件 做出来的很漂亮。。。用PHP干嘛
------解决方案--------------------
给你一个早年写的代码，供参考
<?php //error_reporting(E_ALL ^ E_NOTICE);class Graph { /** * 伪3D绘图类 */ var $im; var $type = "gif"; // png,gif,jpeg,wbmp var $xo; var $yo; var $color; var $fillcolor; var $filldarkcolor; var $filltype = true; var $orgx; var $orgy; var $viewx; var $viewy; var $winx; var $winy; var $extx = 1; var $exty = -1; var $ksin; var $kcos; function Graph() { if(func_num_args() == 2) $this->create(func_get_arc(0),func_get_arc(1)); else $this->create(400,300); } /** * 在($x,$y)处画点 */ function pixel($x,$y) { $p = $this->get_view($x,$y); imagesetpixel($this->im,$p['x'],$p['y'],$this->color); $this->xo = $p['x']; $this->yo = $p['y']; } /** * 移动到($x,$y)处 */ function moveto($x,$y) { $p = $this->get_view($x,$y); $this->xo = $p['x']; $this->yo = $p['y']; } /** * 从($x1,$y1)到($x2,$y2)处画线 */ function line($x1,$y1,$x2,$y2) { $p1 = $this->get_view($x1,$y1); $p2 = $this->get_view($x2,$y2); imageline($this->im,$p1['x'],$p1['y'],$p2['x'],$p2['y'],$this->color); } /** * 从当前位置到($x,$y)处画线 */ function lineto($x,$y) { $p = $this->get_view($x,$y); imageline($this->im, $this->xo, $this->yo, $p['x'], $p['y'], $this->color); $this->xo = $p['x']; $this->yo = $p['y']; } /** * 设置当前颜色 */ function color($clr) { $r = ($clr>>16) & 0xff; $g = ($clr>>8) & 0xff; $b = ($clr) & 0xff; $this->color = ImageColorAllocate($this->im, $r,$g,$b); $this->fillcolor = ImageColorAllocate($this->im, $r,$g,$b); $this->filldarkcolor = ImageColorAllocate($this->im, $r/2,$g/2,$b/2); return $this->color; } /** * 设置当前充填颜色 */ function fillcolor($clr) { $r = ($clr>>16) & 0xff; $g = ($clr>>8) & 0xff; $b = ($clr) & 0xff; $this->fillcolor = ImageColorAllocate($this->im, $r,$g,$b); return $this->fillcolor; } /** * 创建GD句柄并设置坐标系 */ function create($x,$y) { $this->im = imagecreatetruecolor($x,$y);imageantialias($this->im, 1);imagefill($this->im, 0, 0, $this->color(0xffffff)); $this->viewx = $x-1; $this->viewy = -($y-1); $this->winx = $x; $this->winy = $y; $this->orgx = 0; $this->orgy = 0;//$y; $this->colors = $this->color(0xffffff); settype($this->ksin,"double"); settype($this->kcos,"double"); $this->ksin = sin(deg2rad(0)); $this->kcos = cos(deg2rad(0)); } /** * 坐标映射 */ function get_view($x,$y) { $this->xo = $x*$this->kcos - $y*$this->ksin; $this->yo = $x*$this->ksin + $y*$this->kcos; $p['x'] = ($this->xo + $this->orgx)*($this->viewx/$this->winx); $p['y'] = ($this->yo + $this->orgy)*($this->viewy/$this->winy)-$this->viewy; return $p; } /** * 设置限度 */ function set_ext($x,$y=0) { $this->winx = $x; if($y == 0) { $this->winy = - $x * $this->viewy / $this->viewx; }else { $this->winy = $y; } } /** * 设置旋转角 */ function set_r($p) { $this->ksin = sin(deg2rad($p)); $this->kcos = cos(deg2rad($p)); } /** * 构造图形，必需在派生类中重载本方法 */ function paint() { /** * 必需由派生类重载 * 必需包含语句 $this->create(宽度,高度); */ die("paint 方法必需由派生类重载!"); } /** * 输出图形 */ function run() { $this->paint(); $func = "Image".$this->type; if(! function_exists($func)) { $this->type = "png"; $func = "Image".$this->type; } Header("Content-type: image/{$this->type}"); $func($this->im); imageDestroy($this->im); } /** * 圆类图形数据生成，参数$p为坐标旋转角 */ function get_point($ox,$oy,$w,$h,$start,$end) { $a = $w/2; $b = $h/2; $rs = array(); $i = $start; for($i=$start;$iget_view($ox+$x,$oy+$y); $rs[] = $p['x']; $rs[] = $p['y']; if($i == $end) break; if($i+5 > $end) $i = $end - 5; } $p = $this->get_view($ox,$oy); $rs[] = $p['x']; $rs[] = $p['y']; $rs[] = $rs[0]; $rs[] = $rs[1]; return $rs; } /** * 弓形 */ function chord($left,$top,$w,$h,$start,$end,$z=0) { $ar = $this->get_point($left,$top,$w,$h,$start,$end,$p); for($i=0;$i<count>get_view($ar[$i],$ar[$i+1]); $ar[$i] = $p['x']; $ar[$i+1] = $p['y']; } imagefilledpolygon($this->im,$ar,count($ar)/2-1,$this->fillcolor); imagepolygon($this->im,$ar,count($ar)/2-1,$this->color); } /** * 扇形 */ function pie($left,$top,$w,$h,$start,$end,$z=0) { $this->get_view($left,$top+$z); $ar = $this->get_point($left,$top+$z,$w,$h,$start,$end); $this->get_view($left,$top); $arh = $this->get_point($left,$top,$w,$h,$start,$end); for($j=0;$j<count array if>filltype) imagefilledpolygon($this->im,$t,4,$this->filldarkcolor); else imagepolygon($this->im,$t,4,$this->color); } if($this->filltype) imagefilledpolygon($this->im,$ar,count($ar)/2-1,$this->fillcolor); } /** * 弧形 */ function arc($left,$top,$w,$h,$start,$end,$z=0) { $ar = $this->get_point($left,$top,$w,$h,$start,$end,$p); $this->moveto($ar[0],$ar[1]); for($i=2;$i<count>lineto($ar[$i],$ar[$i+1]); }}/** * 重载基类的paint方法 */class myGraph extends Graph { function paint() {// $this->create(400,300); $this->create(200,150);$this->set_ext(400); $this->set_r(10); // 旋转 $this->filltype = false; //充填 $k = 40; //高 $a =200; //中心x $b = 150; //中心y $c = 200; //长轴 $d = 100; //短轴 $this->color(0x000000); $this->color(0xff0000); $this->pie($a,$b,$c,$d,0,100,$k); $this->color(0x00ff00); $this->pie($a,$b,$c,$d,120,240,$k); $this->color(0x0000ff); $this->pie($a+10,$b-10,$c,$d,240,360,$k); $this->color(0x8080ff); $this->pie(50,80,40,20,0,360,50); $this->line($a,0,$a,$b*2); $this->line(0,$b,$a*2,$b); }}$g = new myGraph;$g->run();<div class="clear">
</div></count></count></count>
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
