I'm still new for using three js. When I'm rotating a camera object, there is a rotation property has x,y,z value. I'm wondering where the x,y,z in Object 3D rotation come from? I know the x,y,z represent the radians of Object Euler angle, but according the link three.js document provide:https://en.wikipedia.org/wiki/Euler_angles the range of α and γ covers 2π radians, and the range of β covers π radians. However, the range of all the x,y,z only covers π radians when i test it. From initially x=0,y=0,z=0, straight look up, why only x value changed? And if the Object3D is a camera, is that means the center pixel in the camera view represents the x-axis? Appreciate of your help.
Asked
Active
Viewed 1,725 times
1 Answers
0
You might work on formulating your question a bit clearer and give code to reproduce your error.
On the question why only the x-vaue changes when you look straight up from (0,0,0) is because x, y and z represents the axis that you rotate around. The standard in 3js and in 3D-graphics in general is to have x as the horizontal axis, y as the vertical axis and z is the "depth" axis. Looking straight up you will rotate 90 degrees aound the horiontal x-axis, thus changing the x-value in the rotation.
I can give you the link to https://threejs.org/docs/#api/math/Euler
Three.js provides two ways of representing 3D rotations: Euler angles and Quaternions, as well as methods for converting between the two. Euler angles are subject to a problem called "gimbal lock," where certain configurations can lose a degree of freedom (preventing the object from being rotated about one axis). For this reason, object rotations are always stored in the object's quaternion.
Previous versions of the library included a useQuaternion property which, when set to false, would cause the object's matrix to be calculated from an Euler angle. This practice is deprecated---instead, you should use the setRotationFromEuler method, which will update the quaternion.
https://threejs.org/docs/manual/introduction/Matrix-transformations.html
