Rotate camera around axis
21 October 2016 02:05
Hello again:
I've been trying to rotate a STATIC type camera along the y-axis, the front axis, with the new way to call it. (up-down, x-axis, left-right, z-axis). Well, I wanted to rotate around and I have found is imposible, at least to me.
I have tried via a quaternion and the transform api:
If I use the other axis it works ok, but with the y axis doesn't work. Is this a limitation of the camera or I am doing something wrong?
I've been trying to rotate a STATIC type camera along the y-axis, the front axis, with the new way to call it. (up-down, x-axis, left-right, z-axis). Well, I wanted to rotate around and I have found is imposible, at least to me.
I have tried via a quaternion and the transform api:
var _cam_quat = m_trans.get_rotation(_cam, _vec4_tmp2);
m_quat.rotateY(_cam_quat, _my_rot_y, _cam_quat);
m_trans.set_rotation_v(_cam, _cam_quat);
If I use the other axis it works ok, but with the y axis doesn't work. Is this a limitation of the camera or I am doing something wrong?
21 October 2016 16:05
ello again:Hello!
I've been trying to rotate a STATIC type camera along the y-axis, the front axis, with the new way to call it. (up-down, x-axis, left-right, z-axis). Well, I wanted to rotate around and I have found is imposible, at least to me.
I have tried via a quaternion and the transform api:
var _cam_quat = m_trans.get_rotation(_cam, _vec4_tmp2);
m_quat.rotateY(_cam_quat, _my_rot_y, _cam_quat);
m_trans.set_rotation_v(_cam, _cam_quat);
If I use the other axis it works ok, but with the y axis doesn't work. Is this a limitation of the camera or I am doing something wrong?
Your code snippet looks correct. But if I understand you right, you want roll rotation (wiki), which is rotation around z axis in camera's local coordinate space.
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Also make sure that the camera is really STATIC, roll rotation isn't supported for all camera types. Do you change camera type dynamically?
You as well may rotate camera with m_transform.rotate_z_local method, which performs almost the same routine.
21 October 2016 20:45
Hi:
Yes, it is roll rotation. Along the local z axis of the camera. What I've found is that when I use the y parent rotation and add it to the quaternion via rotateAxis if I use any of the other axis works and the camera rotate but in the wrong direction.
I keep trying…
But if I understand you right, you want roll rotation (wiki), which is rotation around z axis in camera's local coordinate space.
Yes, it is roll rotation. Along the local z axis of the camera. What I've found is that when I use the y parent rotation and add it to the quaternion via rotateAxis if I use any of the other axis works and the camera rotate but in the wrong direction.
I keep trying…
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24 October 2016 09:56
24 October 2016 21:17