Rotation of an Object in 3D Animation

Submitted by a_a on Thu, 09/15/2011 - 21:18.

Despite the fact that you do not want rotate the object regarding a particular axis the physics and mathematics of rotation requires that you provide an axis and an angle. The axis of rotation need not to be just [1 0 0 ] or [0 1 0] or [0 0 1], you can use any axis like [1 1 1]. Well, strictly speaking, it must be normalized, but VisSim will do it for you. Axis coordinates can be non-constant and that makes the rotation more complex.

Submitted by mhdshaheed on Thu, 09/15/2011 - 22:02.

I want to do three things on the object simultaneously. They are: (1). translate the object along the desired path. (2). rotate the object around an axis (say y-axis) (3). rotate the object as a whole or tilt the object by certain angle in a plane.

Now the first one (1) translation is done by providing values to object's 'transform.translation' which is shown in virtual world tree in world3d properties. For the second one (2) I gave input to 'transform.rotation' of the object as [0 1 0 angle]. The operations (2) and (3) are two different performed on the object simultaneously. Since both are rotation operations. I have already used the 'transform.rotation' to perform operation (2). I want to tilt or rotate the object in a plane (say x-y plane) by certain amount. How do I provide this input to the world3d block?

I want to know one more thing. Can we rotate the coordinate system of an object in 3d animation? If so how do we do it.

Submitted by a_a on Thu, 09/15/2011 - 22:20.

You can do that using two nested transform objects. Like Transfor1{ Transform2{Object}} You apply one rotation to Transform1 and another rotation to Transform2.

From mathematical point of view, when you apply transformation to the enclosed transform frame, you rotate object's coordinate system.