javascript - jCanvas 的 globalCompositeOperation

Question

我如何将 globalCompositeOperation(或任何其他可以给我“multiply”颜色操作的插件)集成到 jCanvas 中jQuery 插件？

// How do I get this working? //
var ctx = document.getElementById('canvas').getContext('2d');
ctx.globalCompositeOperation = 'darker';

// With this - //
$("canvas").drawArc({
  fillStyle: "#c7302a",
  x: 100, y: 100,
  radius: 50
});

$("canvas").drawArc({
  fillStyle: "#395797",
  x: 170, y: 100,
  radius: 50,
  opacity: 1
});

Answer 1

郑重声明，jCanvas 有一个compositing 属性，其值映射到ctx.globalCompositeOperation。

$("canvas").drawArc({
  fillStyle: "#c7302a",
  x: 100, y: 100,
  radius: 50,
  compositing: 'darker'
});

-迦勒