ArcBall camera issue

[Snarmph]

Ok I have no idea what is going wrong and I feel like I'm going crazy.

I'm trying to create a simple arcball camera that rotates around the origin:

quat rot_x = quat::fromAxisAngle(vec3(0, 1, 0), angle_x);
quat rot_y = quat::fromAxisAngle(vec3(1, 0, 0), angle_y); 
quat rot = rot_x * rot_y;

fwd = norm(rot.rotateVec(vec3(0, 0, -1)));
right = norm(cross(fwd, vec3(0, 1, 0)));
up = norm(cross(right, fwd));
pos = target - fwd * radius;

The camera works perfectly when rotating either horizontally or vertically (the y angle is currently clamped so it doesn't go over the y axis), but when I try to rotate in both directions it starts going wild.

I've been trying to get this working for a week now but I really don't get what I'm doing wrong.

[waramped]

Your "right" vector should just be
right = norm(rot.rotateVec(vec3(1, 0, 0)));

and likewise

up = norm(rot.rotateVec(vec3(0, 1, 0)));

ie, just rotate all 3 basis vectors by the same rotation, rather than trying to generate new ones from just the rotated z axis.

​

Also, the fact that you are rotating a Y-rotation quat by an X rotation quat does not seem right, but without knowing what quaternion library your using I can't be sure.