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Very cool. Powers of 10, interactive, from "smaller than makes sense" to
"bigger than the visible universe."
http://www.newgrounds.com/portal/view/525347
Now, how many bits do you need in your floats to represent that? :-)
--
Darren New, San Diego CA, USA (PST)
Forget "focus follows mouse." When do
I get "focus follows gaze"?
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Darren New wrote:
> Now, how many bits do you need in your floats to represent that? :-)
Depends. How many bits of precision do you want? :-P
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http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 wrote:
> Darren New wrote:
>
>> Now, how many bits do you need in your floats to represent that? :-)
>
> Depends. How many bits of precision do you want? :-P
Well, that's the trick. It goes from "smaller than makes sense to talk
about" to "bigger than the universe." That's telling you how many bits of
precision you need.
"Smaller" as in "it's nonsensical to talk about distances shorter than that
because physics doesn't work that way", just like "there is no distance
bigger than the entire universe."
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Darren New, San Diego CA, USA (PST)
Forget "focus follows mouse." When do
I get "focus follows gaze"?
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Darren New wrote:
> Orchid XP v8 wrote:
>> Darren New wrote:
>>
>>> Now, how many bits do you need in your floats to represent that? :-)
>>
>> Depends. How many bits of precision do you want? :-P
>
> Well, that's the trick. It goes from "smaller than makes sense to talk
> about" to "bigger than the universe." That's telling you how many bits
> of precision you need.
>
> "Smaller" as in "it's nonsensical to talk about distances shorter than
> that because physics doesn't work that way", just like "there is no
> distance bigger than the entire universe."
Sure. I get that. And if you were asking about *fixed-point* arithmetic,
we could just take some logarithms and get an answer. But since you said
*floating-point*, all we figure out is how many bits the exponent needs.
That still leaves the question of how big the mantissa should be. ;-)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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"Darren New" <dne### [at] san rr com> wrote in message
news:4b6503be@news.povray.org...
> Very cool. Powers of 10, interactive, from "smaller than makes sense" to
> "bigger than the visible universe."
>
> http://www.newgrounds.com/portal/view/525347
>
> Now, how many bits do you need in your floats to represent that? :-)
Single precision is enough for float. For fixed point, you are looking at
around 240 bits.
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Orchid XP v8 wrote:
> Sure. I get that. And if you were asking about *fixed-point* arithmetic,
> we could just take some logarithms and get an answer. But since you said
> *floating-point*, all we figure out is how many bits the exponent needs.
> That still leaves the question of how big the mantissa should be. ;-)
Fair dinkum.
--
Darren New, San Diego CA, USA (PST)
Forget "focus follows mouse." When do
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somebody wrote:
>
> Single precision is enough for float. For fixed point, you are looking at
> around 240 bits.
>
Interestingly, I seem to recall that Java3D has functionality to specify
coordinates using 256-bit fixed point for exactly this reason. I never
made use of that ability though.
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