布尔运算，在多边形$polygon标签上支持，且必须声明multi。多个多边形两两之间进行布尔运算，合减交差（union, diff, intersection, xor）。下面是交集运算前后对比。

csx code

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  1. karas.render(
  2.   <canvas width="360" height="360">
  3.     <$polygon points={[
  4.       [
  5.         [0, 0],
  6.         [0.6, 0],
  7.         [0.6, 0.6],
  8.         [0, 0.6]
  9.       ],
  10.       [
  11.         [0.4, 0.2],
  12.         [1, 0.2],
  13.         [1, 1],
  14.         [0.4, 1]
  15.       ],
  16.     ]} controls={[
  17.       [
  18.         [],
  19.         [0.8, 0.3]
  20.       ],
  21.     ]} multi={true} booleanOperations={['intersection']} style={{
  22.       position: 'absolute',
  23.       left: 20,
  24.       top: 20,
  25.       width: 200,
  26.       height: 200,
  27.       fill: '#F00',
  28.     }}/>
  29.   </canvas>,
  30.   '#example'
  31. );
  32. karas.render(
  33.   <svg width="360" height="360">
  34.     <$polygon points={[
  35.       [
  36.         [0, 0],
  37.         [0.6, 0],
  38.         [0.6, 0.6],
  39.         [0, 0.6]
  40.       ],
  41.       [
  42.         [0.4, 0.2],
  43.         [1, 0.2],
  44.         [1, 1],
  45.         [0.4, 1]
  46.       ],
  47.     ]} controls={[
  48.       [
  49.         [],
  50.         [0.8, 0.3]
  51.       ],
  52.     ]}  multi={true} style={{
  53.       position: 'absolute',
  54.       left: 20,
  55.       top: 20,
  56.       width: 200,
  57.       height: 200,
  58.       fill: '#F00',
  59.     }}/>
  60.   </svg>,
  61.   '#example2'
  62. );
karas.render(
  <canvas width="360" height="360">
    <$polygon points={[
      [
        [0, 0],
        [0.6, 0],
        [0.6, 0.6],
        [0, 0.6]
      ],
      [
        [0.4, 0.2],
        [1, 0.2],
        [1, 1],
        [0.4, 1]
      ],
    ]} controls={[
      [
        [],
        [0.8, 0.3]
      ],
    ]} multi={true} booleanOperations={['intersection']} style={{
      position: 'absolute',
      left: 20,
      top: 20,
      width: 200,
      height: 200,
      fill: '#F00',
    }}/>
  </canvas>,
  '#example'
);
karas.render(
  <svg width="360" height="360">
    <$polygon points={[
      [
        [0, 0],
        [0.6, 0],
        [0.6, 0.6],
        [0, 0.6]
      ],
      [
        [0.4, 0.2],
        [1, 0.2],
        [1, 1],
        [0.4, 1]
      ],
    ]} controls={[
      [
        [],
        [0.8, 0.3]
      ],
    ]}  multi={true} style={{
      position: 'absolute',
      left: 20,
      top: 20,
      width: 200,
      height: 200,
      fill: '#F00',
    }}/>
  </svg>,
  '#example2'
);