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Craigtut/portraitRotation.js

Created December 6, 2018 00:42
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Clockwise rotation with translation.
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portraitRotation.js
// event from touch event on a view
const { pageX, pageY } = event.nativeEvent;
const x0 = pageX / Metrics.screenWidth;
const y0 = pageY / Metrics.screenHeight;
const x = y0;
const y = -x0 + 1;
// x and y have now been rotated 90 deg clockwise and translated back into normalized coordinates.
@havanthanhit
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what's the Metrics?

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