On Sun, 3 Oct 1999 09:27:54 -0400, "Spock" <spo### [at] homecom> wrote:

>Ok, I went through the same learning curve and came out with
>the same answer, so here is an interesting follow-up question:
>
>Can you tell me the formula for determining where in 3space I
>am after this sort of translate/rotate action.  For example if I
>wanted the camera to follow the rotating object (but not from
>the origin :-) I need to "look_at" the <x,y,z> resulting from your
>transformation.  Any ideas?

Here's a example of what Chris explained:

sphere 
{ <4,1,2>, 1 
  translate <-1,4,2> 
  scale <2,1,2> 
  rotate <-30,0,-30>
}

The center of the sphere will end up at:
vrotate( (<4,1,2>+<-1,4,2>)*<2,1,2>, <-30,0,-30> )

Pay close attention to operator precedence!


Peter Popov
ICQ: 15002700

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