31 lines
700 B
JavaScript
31 lines
700 B
JavaScript
/**
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @format
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* @flow
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*/
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/* eslint no-bitwise: 0 */
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'use strict';
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/**
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* number should be a color processed by `normalizeColor`
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* alpha should be number between 0 and 1
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*/
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function setNormalizedColorAlpha(input: number, alpha: number): number {
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if (alpha < 0) {
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alpha = 0;
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} else if (alpha > 1) {
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alpha = 1;
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}
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alpha = Math.round(alpha * 255);
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// magic bitshift guarantees we return an unsigned int
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return ((input & 0xffffff00) | alpha) >>> 0;
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}
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module.exports = setNormalizedColorAlpha;
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