37 lines
811 B
JavaScript
37 lines
811 B
JavaScript
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export function calcRotationMatrix(vec, rad) {
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// Equation used from:
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// https://people.eecs.berkeley.edu/~ug/slide/pipeline/assignments/as5/rotation.html
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let A = glMatrix.mat3.fromValues(
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0,
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-vec[2],
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vec[1],
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vec[2],
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0,
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-vec[0],
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-vec[1],
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vec[0],
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0,
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);
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let I = glMatrix.mat3.create();
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// Matrix Exponential
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let Mpow = glMatrix.mat3.create();
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glMatrix.mat3.mul(Mpow, A, A);
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let M1 = glMatrix.mat3.create();
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let M2 = glMatrix.mat3.create();
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// Scalar Multiplications
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glMatrix.mat3.multiplyScalar(M1, A, Math.sin(rad));
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glMatrix.mat3.multiplyScalar(M2, Mpow, 1 - Math.cos(rad));
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// Matrix Addition
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let M3 = glMatrix.mat3.create();
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let Q = glMatrix.mat3.create();
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glMatrix.mat3.add(M3, I, M1);
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glMatrix.mat3.add(Q, M3, M2);
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return Q;
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}
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