Lack in docs about 3D coordinates
Hi everybody,
I am new in breve. Just read docs. What is strange, can't find clear description of what is rotation matrix in definition of stationary objects' positions. That is not really clear in docs.
Could anyone explaine me here how to operate with center coordinate of some cube and with that matrix?
I mean, what do these three vectors mean? If I would like to turn the cube somehow, what numbers and how they should be set into the matrix?
Sorry if this is silly note and question.
With best wishes for all,
Aliale
Hi Aliale, I believe you
Hi Aliale, I believe you will need to brush up on vector mathmatics. I am also new to breve, but I know this topic is described in my old linear algebra text book. Basically, my understanding is that a matrix is a method to do mathmatical operations on a vector. I believe if you google linear algebra the vector topic will show up. If you want when I find my text, I will post some examples. This may be difficult since some notations are hard to show in HTML.
I know linear algebra...
Hi,
Thanks for a reply. It should be so as you write, every new coordinate of some body in local reference system should be obtained by matrix multiplication of the body's coordinates and this matrix. Yet it can be somehow not so. Nobody knows, what author can invent.
Even if this is standard linear algebra, it should be given some help for impatient users how to construct this matrix with some vectors and angles for turns and so on. I did such a task in 2D, and I know formula to calculate numbers in the 2D matrix to make these turns definite. It looks not pretty again to do the same for 3D. That should be in docs.
No need for a matrix?
Matrices can be complicated to work with. breve offers other ways to preform rotations which are much easier to use. All of these methods are found in the Mobile class:
- jon
Thanks, that was expected.
Hi, Jon
Jag kan prata lite Svenska. Bodde i Sundsvall två år.
But it's better to talk here in English. The question is about usability of these methods to set rotation in Stationary classes. I usually read documentation before writing some code. Just want to know, should I manually add these methods to the stationary objects? There is no mention of these methods in Real and Shape classes. How do the stationary objects will know about ones? Or there is common name space in all the system? Anyway, methods should be inherited somehow and this is not evident how it is or should be.