[Date Index] [Thread Index] [Author Index]

3D calculations

• To: mathgroup at smc.vnet.net
• Subject: [mg2592] 3D calculations
• From: masa at maskos.pp.fi (Matti Koskimies)
• Date: Mon, 27 Nov 1995 21:32:56 -0500

Hi all!

I have some problems in programming a 3d cube (don't get mad -this is pure
math question). The problem is in swithing 3D polar koordinates to 2D rectangular
koordinates. I use two degrees: first from Yaxis to Zaxis and another from X to Z
(and radius is 50).

I think that this system should work with one point:

x=rad*sin(yz)*cos(yz)
y=rad*sin(yz)*sin(yz)

Let's say that this point is the right upper corner of the cube (the one nearest one):
now I can have all upper points if I make a 4 step loop and always add 90 gedrees to the
xz value. but here is the broplem: what do I have do if the cube is turned for example
so that the uppest plane points 80 degrees to right?

Thanks for replying!!!
(I'd be really happy if you used e-mail...)

Matti Koskimies