28 lines
442 B
JavaScript
28 lines
442 B
JavaScript
module.exports = invert
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/**
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* Inverts a mat2
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*
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* @alias mat2.invert
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* @param {mat2} out the receiving matrix
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* @param {mat2} a the source matrix
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* @returns {mat2} out
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*/
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function invert(out, a) {
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var a0 = a[0]
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var a1 = a[1]
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var a2 = a[2]
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var a3 = a[3]
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var det = a0 * a3 - a2 * a1
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if (!det) return null
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det = 1.0 / det
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out[0] = a3 * det
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out[1] = -a1 * det
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out[2] = -a2 * det
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out[3] = a0 * det
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return out
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}
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