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确定旋转矩形的尺寸
此堆栈代码段在黑色背景上绘制了一个别名白色矩形,并为其尺寸,位置,角度和网格尺寸提供了参数: <style>html *{font-family:Consolas,monospace}input{width:24pt;text-align:right;padding:1px}canvas{border:1px solid gray}</style><p>grid w:<input id='gw' type='text' value='60'> grid h:<input id='gh' type='text' value='34'> w:<input id='w' type='text' value='40'> h:<input id='h' type='text' value='24'> x:<input id='x' type='text' value='0'> y:<input id='y' type='text' value='0'> &theta;:<input id='t' type='text' value='12'>&deg; <button type='button' onclick='go()'>Go</button></p>Image<br><canvas id='c'>Canvas not supported</canvas><br>Text<br><textarea id='o' rows='36' cols='128'></textarea><script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script><script>function toCart(t,a,n,r){return{x:t-n/2,y:r/2-a}}function vtx(t,a,n){return{x:n.x+t*Math.cos(a),y:n.y+t*Math.sin(a)}}function sub(t,a){return{x:t.x-a.x,y:t.y-a.y}}function dot(t,a){return t.x*a.x+t.y*a.y}function inRect(t,a,n,r){var …