phaser/v3/src/math/interpolation/CatmullRomInterpolation.js

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var CatmullRom = require('../CatmullRom');
var CatmullRomInterpolation = function (v, k)
{
var m = v.length - 1;
var f = m * k;
var i = Math.floor(f);
if (v[0] === v[m])
{
if (k < 0)
{
i = Math.floor(f = m * (1 + k));
}
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return CatmullRom(f - i, v[(i - 1 + m) % m], v[i], v[(i + 1) % m], v[(i + 2) % m]);
}
else
{
if (k < 0)
{
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return v[0] - (CatmullRom(-f, v[0], v[0], v[1], v[1]) - v[0]);
}
if (k > 1)
{
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return v[m] - (CatmullRom(f - m, v[m], v[m], v[m - 1], v[m - 1]) - v[m]);
}
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return CatmullRom(f - i, v[i ? i - 1 : 0], v[i], v[m < i + 1 ? m : i + 1], v[m < i + 2 ? m : i + 2]);
}
};
module.exports = CatmullRomInterpolation;