mirror of https://github.com/jkjoy/sunpeiwen.git
39 lines
748 B
JavaScript
39 lines
748 B
JavaScript
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var nodes = require('../nodes')
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, rgba = require('./rgba');
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/**
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* Return the alpha component of the given `color`,
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* or set the alpha component to the optional second `value` argument.
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*
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* Examples:
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*
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* alpha(#fff)
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* // => 1
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*
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* alpha(rgba(0,0,0,0.3))
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* // => 0.3
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*
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* alpha(#fff, 0.5)
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* // => rgba(255,255,255,0.5)
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*
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* @param {RGBA|HSLA} color
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* @param {Unit} [value]
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* @return {Unit|RGBA}
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* @api public
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*/
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function alpha(color, value){
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color = color.rgba;
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if (value) {
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return rgba(
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new nodes.Unit(color.r),
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new nodes.Unit(color.g),
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new nodes.Unit(color.b),
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value
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);
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}
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return new nodes.Unit(color.a, '');
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};
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alpha.params = ['color', 'value'];
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module.exports = alpha;
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