"Dennis Miller" <dhm### [at] comcastnet> wrote in
news:3f6fb81f$1@news.povray.org: 

> Hi. You can declare as many parameters as you want for the
> position of the object using the macro, so you could have
> one declaration for the y position and one for the z. Only
> two things you need to specify: the time for some event and
> the value at that point. So if you can describe the motion
> in the y axis as a pair of values - a point in time and the
> value at that point - then you can basically move any way
> you want. The only other thing to determine is if you want
> the motion between points to be linear or not (options are
> speeding up, slowing down, the Bounce factor you mentioned,
> etc). But you could describe the motion "manually" for any
> of those types of motions.
> So declare the y factor :
>  #declare Y = (From (0, 0)  To (.250, -1)  To (.625, -1) 
>  To (1, 0)  ) ; 
> 
> independent from the z:
>  #declare Z = (From (0, 0)  To (.250, 1)  To (.625, 1)   )
>  ; translate <0,Y,Z>

You see, I didn't think of using it that way, via a declare
for each axis, it's a lot easier to implement and understand.

I tried all kinds of weird combos, but your way makes a whole
lot of sense. 
 
> these are just examples; you can have as many "breakpoints"
> as you need by just declaring ever more points in time and
> the associated value... 
> 
> Not sure if this is what is stumping you; if you don't

If it works as you say it does then it should un-stump me!

> declare a type of motion, then the points are just
> interpolated linearly. But if you <choose> to include the
> type of motion between points in the declaration, keep in 
> mind that once you use a motion type:
>  #declare Y = (From (0, 0)  To_Using (.250, 1,"B")  To
>  (.625, 1)  To (1, 
> )  ) ;
>
> then that motion type remains in effect for the rest of the
> points, so you have to "disable" to use another type:
>  #declare Y = (From (0, 0)  To_Using (.250, 1,"B") 
>  To_Using (.625, 1, "L") 
> To (1, 0)  ) ;

This I had understood.

> not sure if that helps, but you just set up a different
> type of motion for y and z... And you can scale or offset
> any of these if you wanted to keep everything positive or
> negative. Is that what you are looking for?

I sure will give it a try, I'll keep you posted!

Thanks D.

-- 
Marc Champagne
marcch.AT.videotron.DOT.ca
Montreal, CANADA

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