grey/BOSL2
1
0
Fork 0
mirror of https://github.com/BelfrySCAD/BOSL2.git synced 2025-01-01 09:49:45 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Added Q_Axis(), Q_Angle()

Browse source
This commit is contained in:
Revar Desmera 2019-02-06 03:32:27 -08:00
parent 54af28d8c4
commit 7450797edc
1 changed files with 23 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

25
quaternions.scad
View file

@ -37,7 +37,20 @@ use <math.scad>
// Quaternions are stored internally as a 4-value vector:
// [X, Y, Z, W] = W + Xi + Yj + Zk
function _Quat(a,s,w) = [a[0]*s, a[1]*s, a[2]*s, w];
function Quat(ax, ang) = _Quat(ax/norm(ax), sin(ang/2), cos(ang/2));
function Quat(ax=[0,0,1], ang=0) = _Quat(ax/norm(ax), sin(ang/2), cos(ang/2));
function QuatX(a=0) = Quat([1,0,0],a);
function QuatY(a=0) = Quat([0,1,0],a);
function QuatZ(a=0) = Quat([0,0,1],a);
// Creates a quaternion from standard [X,Y,Z] euller rotation angles in degrees.
function QuatEuller(a=[0,0,0]) =
let(
qx = QuatX(a[0]),
qy = QuatY(a[1]),
qz = QuatZ(a[2])
)
Q_Mul(qz, Q_Mul(qy, qx));
function Q_Ident() = [0, 0, 0, 1];
@ -91,7 +104,15 @@ function Q_Matrix4(q) = [
];
// Returns the vector v after rotating it by the quaternion q.
// Returns the quaternion's axis of rotation as a vector.
function Q_Axis(q) = let(d = sqrt(1-(q[3]*q[3]))) (d==0)? [0,0,1] : [q[0]/d, q[1]/d, q[2]/d];
// Returns the quaternion's angle of rotation in degrees.
function Q_Angle(q) = 2 * acos(q[3]);
// Returns the vector `v` after rotating it by the quaternion `q`.
function Q_Rot_Vector(v,q) = Q_Mul(Q_Mul(q,concat(v,0)),Q_Conj(q));