59 lines
1.5 KiB
JavaScript
59 lines
1.5 KiB
JavaScript
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/**
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* Copyright (c) Nicolas Gallagher.
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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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*
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*/
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import Dimensions from '../Dimensions';
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/**
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* PixelRatio gives access to the device pixel density.
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*/
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var PixelRatio =
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/*#__PURE__*/
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function () {
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function PixelRatio() {}
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/**
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* Returns the device pixel density.
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*/
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PixelRatio.get = function get() {
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return Dimensions.get('window').scale;
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}
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/**
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* No equivalent for Web
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*/
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;
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PixelRatio.getFontScale = function getFontScale() {
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return Dimensions.get('window').fontScale || PixelRatio.get();
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}
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/**
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* Converts a layout size (dp) to pixel size (px).
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* Guaranteed to return an integer number.
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*/
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;
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PixelRatio.getPixelSizeForLayoutSize = function getPixelSizeForLayoutSize(layoutSize) {
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return Math.round(layoutSize * PixelRatio.get());
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}
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/**
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* Rounds a layout size (dp) to the nearest layout size that corresponds to
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* an integer number of pixels. For example, on a device with a PixelRatio
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* of 3, `PixelRatio.roundToNearestPixel(8.4) = 8.33`, which corresponds to
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* exactly (8.33 * 3) = 25 pixels.
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*/
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;
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PixelRatio.roundToNearestPixel = function roundToNearestPixel(layoutSize) {
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var ratio = PixelRatio.get();
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return Math.round(layoutSize * ratio) / ratio;
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};
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return PixelRatio;
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}();
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export { PixelRatio as default };
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