Warp / Mike : (acknowledged, nod, understood);

I am in a big "collecting" mode right now (searching for and downloading
..inc, macros, tutorials - catching up here, I used to be quite proficient
thru PoV 3.1g) and not rendering and experimenting as fast as I need to
(slow computer + waiting for answers for a couple of things, including
*this* issue - also doing some interim research)... but in a couple of days
I will start aggressive experiments to determine the (*approximate) answer
to this question... UNLESS someone can make it easy for me and give me
definite details about the inner workings of PoV (3.6.1) (on *this* issue).
I need someone who progammed PoV to stop by....

Warp: (nod) Yes, that seems to be the case ( " ... artificial limits IMPOSED
.... ") (I just need to know what those limits are, what conditions, what
parameters, "hidden gotcha's", etc.).

I have a couple of clues:

sphere { <0,0,0>,9999999 texture {MyStarField scale x.xx}}
 *OR*
sphere { <0,0,0>,1 texture {MyStarField scale x.xx} scale 9999999}
// size of "Star Sphere" is 9,999,999

.... seems to render properly (if the camera is at <0,0,0> looking at
<0,0,1>). However increase the radius by one to 10,000,000 and the texture
below the x-z plane fails to render (everything below the horizon is
black). Start EXCEEDING 10,000,000 and the texture fails completely.

And I don't know at this time if, when I start to move my camera or change
my angle xx.x, whether 9,999,999 will still work (I will have to check it,
haven't experimented yet).

I tried the "generate lots of objects" method for starfield generation
(actually gave up when just generating 50 "stars" took too long, in a
*restricted* range, *only visible in the camera* I.E. all 50 were on the
screen...); using big triangles as stars, they start to fail to render at
*less than* 9,999,999 (I forget exactly where). Discs (angled, facing the
camera via generating / defining a big disc at <0,0,0>, then translating to
<0,0,9999990>, then adding random X and Y angles via rotate <RandXAngle,
RandYAngle,0>) are okay thru 9,999,990 but fail to show up at 9,999,991.
Spheres are have more tolerance than triangles. Again, change my camera and
that limit of 9,999,990 MIGHT be different.

Again, the main reason for this is "Outer Space" scenes. The focus will be
on objects (spacecraft, space stations, smaller asteroids, other stuff) -
scaled in meters, and my unit expressed in PoV will be in meters. But if my
limit is 9,999,999 meters / 9999.9 kilometers (because of the apparant
MAXIMUM size of StarSpheres - the most distant object) then my room to
"play around in" is limited. I can't model star systems (Stars, Planets,
Big Asteroids, Asteroid Fields) accurately, I have to use tricks (make big
objects smaller and closer than they should be). Consider that a *typical*
star (as I am defining it) : using The Sun as an example, has a radius of
695,500 Km. A typical planet, earth-sized, is Earth 6378 Km.

I supposed I could express as 1 PoV unit = 1 Km to make things "better", but
then spacecraft would be modelled in thousands of kiliometers - hehehe
kinda dumb.

So - what I need to know are details about those "internal numvber limits".

Anybody know the PoV programmers?

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