On 30-Nov-2002, "Thorsten Froehlich" <tho### [at] trfde> wrote:

> > But if the max intersection distance (which is 10^7 according to
> > frame.h)
> > would be the issue here shouldn't all objects dissapear at the same
> > distance then?
>
> Not really, the issue is a bit more complex.  To simplify it, think of it
> as
> if there is just no guarantee made that any object placed more than 10^7
> away from the camera will behave as expected.

So I moved the decimal place over 3 locations (I was using 1unit=1Km) and
the problem with disappering items goes away. This hard-coded limitation
should defintely be described somewhere. (I know the documentation does
not talk about computational limits, as they would be machine specific).

The whole Idea behind floats is that the magnitude is really irrelevant,
only
the number of digits of accuracy should be a constraint, I am still getting
artifacting at the 7th digit of accuracy and that just seems to be a
limitation
of the system and is not good, but can be managed.

So searching for other hard-coded limits in the program I downloading the
source.
There I notice a value "small tolerance" of 0.001 is this another limit of
the program
that people have to be aware of?
If I have scene do I have to keep all my values above this number as well?

I also see that someone has defined pi to 22 digits of accuracy obviously
all of
these digits are not used.

Bounding boxes only use single floats rather than double I can't imagine
why this is so, or what effects this will have on code.

Also the mesh functions seem to use singles, I don't know if this would
cause
issues depending on the size/accuracy of the scene objects, perhaps someone
more knowledgable could comment on this.

All of these need to be definitely documented somewhere in the help files /
FAQ.

My problem is that I wanted to create an animation zooming in from
extra-solar
system to close earth orbit, so I will have to probably break it up into
several parts
with increasing accuracy in each source file in order to get PoV to perform
this task.

	-Dan

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