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fromXRotation.js
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fromXRotation.js
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module.exports = fromXRotation
/**
* Creates a matrix from the given angle around the X axis
* This is equivalent to (but much faster than):
*
* mat4.identity(dest)
* mat4.rotateX(dest, dest, rad)
*
* @param {mat4} out mat4 receiving operation result
* @param {Number} rad the angle to rotate the matrix by
* @returns {mat4} out
*/
function fromXRotation(out, rad) {
var s = Math.sin(rad),
c = Math.cos(rad)
// Perform axis-specific matrix multiplication
out[0] = 1
out[1] = 0
out[2] = 0
out[3] = 0
out[4] = 0
out[5] = c
out[6] = s
out[7] = 0
out[8] = 0
out[9] = -s
out[10] = c
out[11] = 0
out[12] = 0
out[13] = 0
out[14] = 0
out[15] = 1
return out
}