@thewtex/vtk.js-esm
Version:
Visualization Toolkit for the Web
331 lines (300 loc) • 8.86 kB
JavaScript
import { A as ARRAY_TYPE, E as EPSILON } from './common.js';
import { c as create$2 } from './mat3.js';
import { w as create$1, x as fromValues$2, d as dot, c as cross, r as len, n as normalize$1 } from './vec3.js';
import { f as fromValues$1, n as normalize$2 } from './vec4.js';
/**
* Quaternion
* @module quat
*/
/**
* Creates a new identity quat
*
* @returns {quat} a new quaternion
*/
function create() {
var out = new ARRAY_TYPE(4);
if (ARRAY_TYPE != Float32Array) {
out[0] = 0;
out[1] = 0;
out[2] = 0;
}
out[3] = 1;
return out;
}
/**
* Sets a quat from the given angle and rotation axis,
* then returns it.
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyVec3} axis the axis around which to rotate
* @param {Number} rad the angle in radians
* @returns {quat} out
**/
function setAxisAngle(out, axis, rad) {
rad = rad * 0.5;
var s = Math.sin(rad);
out[0] = s * axis[0];
out[1] = s * axis[1];
out[2] = s * axis[2];
out[3] = Math.cos(rad);
return out;
}
/**
* Gets the rotation axis and angle for a given
* quaternion. If a quaternion is created with
* setAxisAngle, this method will return the same
* values as providied in the original parameter list
* OR functionally equivalent values.
* Example: The quaternion formed by axis [0, 0, 1] and
* angle -90 is the same as the quaternion formed by
* [0, 0, 1] and 270. This method favors the latter.
* @param {vec3} out_axis Vector receiving the axis of rotation
* @param {ReadonlyQuat} q Quaternion to be decomposed
* @return {Number} Angle, in radians, of the rotation
*/
function getAxisAngle(out_axis, q) {
var rad = Math.acos(q[3]) * 2.0;
var s = Math.sin(rad / 2.0);
if (s > EPSILON) {
out_axis[0] = q[0] / s;
out_axis[1] = q[1] / s;
out_axis[2] = q[2] / s;
} else {
// If s is zero, return any axis (no rotation - axis does not matter)
out_axis[0] = 1;
out_axis[1] = 0;
out_axis[2] = 0;
}
return rad;
}
/**
* Multiplies two quat's
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyQuat} a the first operand
* @param {ReadonlyQuat} b the second operand
* @returns {quat} out
*/
function multiply(out, a, b) {
var ax = a[0],
ay = a[1],
az = a[2],
aw = a[3];
var bx = b[0],
by = b[1],
bz = b[2],
bw = b[3];
out[0] = ax * bw + aw * bx + ay * bz - az * by;
out[1] = ay * bw + aw * by + az * bx - ax * bz;
out[2] = az * bw + aw * bz + ax * by - ay * bx;
out[3] = aw * bw - ax * bx - ay * by - az * bz;
return out;
}
/**
* Performs a spherical linear interpolation between two quat
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyQuat} a the first operand
* @param {ReadonlyQuat} b the second operand
* @param {Number} t interpolation amount, in the range [0-1], between the two inputs
* @returns {quat} out
*/
function slerp(out, a, b, t) {
// benchmarks:
// http://jsperf.com/quaternion-slerp-implementations
var ax = a[0],
ay = a[1],
az = a[2],
aw = a[3];
var bx = b[0],
by = b[1],
bz = b[2],
bw = b[3];
var omega, cosom, sinom, scale0, scale1; // calc cosine
cosom = ax * bx + ay * by + az * bz + aw * bw; // adjust signs (if necessary)
if (cosom < 0.0) {
cosom = -cosom;
bx = -bx;
by = -by;
bz = -bz;
bw = -bw;
} // calculate coefficients
if (1.0 - cosom > EPSILON) {
// standard case (slerp)
omega = Math.acos(cosom);
sinom = Math.sin(omega);
scale0 = Math.sin((1.0 - t) * omega) / sinom;
scale1 = Math.sin(t * omega) / sinom;
} else {
// "from" and "to" quaternions are very close
// ... so we can do a linear interpolation
scale0 = 1.0 - t;
scale1 = t;
} // calculate final values
out[0] = scale0 * ax + scale1 * bx;
out[1] = scale0 * ay + scale1 * by;
out[2] = scale0 * az + scale1 * bz;
out[3] = scale0 * aw + scale1 * bw;
return out;
}
/**
* Calculates the conjugate of a quat
* If the quaternion is normalized, this function is faster than quat.inverse and produces the same result.
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyQuat} a quat to calculate conjugate of
* @returns {quat} out
*/
function conjugate(out, a) {
out[0] = -a[0];
out[1] = -a[1];
out[2] = -a[2];
out[3] = a[3];
return out;
}
/**
* Creates a quaternion from the given 3x3 rotation matrix.
*
* NOTE: The resultant quaternion is not normalized, so you should be sure
* to renormalize the quaternion yourself where necessary.
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyMat3} m rotation matrix
* @returns {quat} out
* @function
*/
function fromMat3(out, m) {
// Algorithm in Ken Shoemake's article in 1987 SIGGRAPH course notes
// article "Quaternion Calculus and Fast Animation".
var fTrace = m[0] + m[4] + m[8];
var fRoot;
if (fTrace > 0.0) {
// |w| > 1/2, may as well choose w > 1/2
fRoot = Math.sqrt(fTrace + 1.0); // 2w
out[3] = 0.5 * fRoot;
fRoot = 0.5 / fRoot; // 1/(4w)
out[0] = (m[5] - m[7]) * fRoot;
out[1] = (m[6] - m[2]) * fRoot;
out[2] = (m[1] - m[3]) * fRoot;
} else {
// |w| <= 1/2
var i = 0;
if (m[4] > m[0]) i = 1;
if (m[8] > m[i * 3 + i]) i = 2;
var j = (i + 1) % 3;
var k = (i + 2) % 3;
fRoot = Math.sqrt(m[i * 3 + i] - m[j * 3 + j] - m[k * 3 + k] + 1.0);
out[i] = 0.5 * fRoot;
fRoot = 0.5 / fRoot;
out[3] = (m[j * 3 + k] - m[k * 3 + j]) * fRoot;
out[j] = (m[j * 3 + i] + m[i * 3 + j]) * fRoot;
out[k] = (m[k * 3 + i] + m[i * 3 + k]) * fRoot;
}
return out;
}
/**
* Creates a new quat initialized with the given values
*
* @param {Number} x X component
* @param {Number} y Y component
* @param {Number} z Z component
* @param {Number} w W component
* @returns {quat} a new quaternion
* @function
*/
var fromValues = fromValues$1;
/**
* Normalize a quat
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyQuat} a quaternion to normalize
* @returns {quat} out
* @function
*/
var normalize = normalize$2;
/**
* Sets a quaternion to represent the shortest rotation from one
* vector to another.
*
* Both vectors are assumed to be unit length.
*
* @param {quat} out the receiving quaternion.
* @param {ReadonlyVec3} a the initial vector
* @param {ReadonlyVec3} b the destination vector
* @returns {quat} out
*/
(function () {
var tmpvec3 = create$1();
var xUnitVec3 = fromValues$2(1, 0, 0);
var yUnitVec3 = fromValues$2(0, 1, 0);
return function (out, a, b) {
var dot$1 = dot(a, b);
if (dot$1 < -0.999999) {
cross(tmpvec3, xUnitVec3, a);
if (len(tmpvec3) < 0.000001) cross(tmpvec3, yUnitVec3, a);
normalize$1(tmpvec3, tmpvec3);
setAxisAngle(out, tmpvec3, Math.PI);
return out;
} else if (dot$1 > 0.999999) {
out[0] = 0;
out[1] = 0;
out[2] = 0;
out[3] = 1;
return out;
} else {
cross(tmpvec3, a, b);
out[0] = tmpvec3[0];
out[1] = tmpvec3[1];
out[2] = tmpvec3[2];
out[3] = 1 + dot$1;
return normalize(out, out);
}
};
})();
/**
* Performs a spherical linear interpolation with two control points
*
* @param {quat} out the receiving quaternion
* @param {ReadonlyQuat} a the first operand
* @param {ReadonlyQuat} b the second operand
* @param {ReadonlyQuat} c the third operand
* @param {ReadonlyQuat} d the fourth operand
* @param {Number} t interpolation amount, in the range [0-1], between the two inputs
* @returns {quat} out
*/
(function () {
var temp1 = create();
var temp2 = create();
return function (out, a, b, c, d, t) {
slerp(temp1, a, d, t);
slerp(temp2, b, c, t);
slerp(out, temp1, temp2, 2 * t * (1 - t));
return out;
};
})();
/**
* Sets the specified quaternion with values corresponding to the given
* axes. Each axis is a vec3 and is expected to be unit length and
* perpendicular to all other specified axes.
*
* @param {ReadonlyVec3} view the vector representing the viewing direction
* @param {ReadonlyVec3} right the vector representing the local "right" direction
* @param {ReadonlyVec3} up the vector representing the local "up" direction
* @returns {quat} out
*/
(function () {
var matr = create$2();
return function (out, view, right, up) {
matr[0] = right[0];
matr[3] = right[1];
matr[6] = right[2];
matr[1] = up[0];
matr[4] = up[1];
matr[7] = up[2];
matr[2] = -view[0];
matr[5] = -view[1];
matr[8] = -view[2];
return normalize(out, fromMat3(out, matr));
};
})();
export { conjugate as a, create as c, fromValues as f, getAxisAngle as g, multiply as m, setAxisAngle as s };