hi there my name is Adam and I am currently working on this POV-RAY picture.
but I am stuck, before I tell you what I am stuck on I thought I should give
you some back ground info on what it is I am stuck on. just so you know what
it is I am going on about.

if we take for example: - (this simple shape)

sphere
{

<0.68,(0.425/2)+0.09,0>0.1
translate <0,0.85,0>
scale <0.75,0.75,0.75>
rotate < 10 ,-45, -20>
translate <-0.7,-0.1, 00>
pigment{Red}
}

you can see that its position in 3D space is given by many commands, first a
location which is moved then rotated and then scaled and then moved again.
by this time the shape is getting dizzy.

but through extrapolation you can eliminate each of these steps to exactly
the same shape in the same XYZ coordinates and the same size.

E.G..

<0.68,(0.425/2)+0.09,0> translated by <0,0.85,0> becomes <0.68,0.3025,0.00>

<0.68,(0.425/2)+0.09,0>
+                   <0,0.85,0>
=      <0.68,0.3025,0.00>

do you see ?? well I hope so because that is just the beginning....

NEXT

<0.68,0.3025,0.00> is Scaled by <0.75,0.75,0.75> which can be turned into
<0.51,0.8643750,0.00>
<0.68,0.3025,0.00>
*  <0.75,0.75,0.75>
= <0.51,0.8643750,0.00>

SO if we now uses the code: -

 <0.51,0.8643750,0>0.1
 rotate < 10 ,-45, -20>
 translate <-0.7,-0.1, 00>
 pigment{Red}
 }

basically all we have done is taken

(  <0.68,(0.425/2)+0.09,0>  +  <0,0.85,0>  )  *  <0.75,0.75,0.75

= <0.51,0.8643750,0>

 [ we have extrapolated these new co-ordinates from some existing ones and a
set of instructions ]

we get exactly the same shape in the same place and it is much easier to
understand exactly where it is.

but this is where I get stuck you may notice there is a rotation left in the
statement, and also another translation. I can do the translation that is
easy. It is the rotation that I am finding hard. as you will know if you
move an object and then choose to rotate it, it rotates as through a piece
of string is attached to <0,0,0> what is that I here you say why not rotate
the object before I move it. well because then it will not be in the exact
right place and I will have to start moving it little by little in my scene
to get it in just the right place. and that would take far to long. what I
need is a way or a formula so that I can take my existing co-ordinates and
then by using some method of rotational extrapolation gain the new set of
co-ordinates. in a similar way that I managed to do the examples above.

if some one out there can tell me how you do this then not only would I be
most grateful BUT I will make a windows application that will allow people
to easily do extrapolation in the future and I will make it totally free for
every one at POV-RAY to use. that is after I have finished making the dam
thing.

please there must be some POV-RAY guru out there that can help me
extrapolate these new co-ordinates from this rotational statement. if you
can help me then please feel free to email me at this address
Fie### [at] emailcom

thanks

Adam =B)

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