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36 lines
1.1 KiB
36 lines
1.1 KiB
'use strict';
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const { promisify } = require('util')
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, randomRange = promisify(require('crypto').randomInt);
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module.exports = async (width, height, numDistorts, distortion) => {
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const distorts = [];
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const randNumDistorts = await randomRange(numDistorts.min, numDistorts.max + 1);
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//divide the width by number of distortions and add a distortion across the whole horizontal area
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const div = width/randNumDistorts;
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for (let i = 0; i < randNumDistorts; i++) {
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//start and end of divided width
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const divStart = Math.floor(div * i)
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, divEnd = Math.floor(div * (i + 1));
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//origin coordinate for distortion point
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const originx = await randomRange(divStart, divEnd)
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, originy = await randomRange(0, height);
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//destionation coordinate for distortion point
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const destx = await randomRange(Math.max(distortion, originx - distortion), Math.min(width - distortion, originx + distortion)+1)
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, desty = await randomRange(Math.max(distortion, originy - (distortion * 2)), Math.min(height - distortion, originy + (distortion * 2))+1);
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distorts.push([
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{x:originx,y:originy},
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{x:destx,y:desty}
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]);
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}
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return distorts;
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};
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