On 05/06/2010 03:49 PM, Thomas de Groot wrote:
> Additionally, what you can use to good effect, is the prob() function.

   prob()??? ...I've never heard of that function. In fact, the only thing I
can find is prod(), which was also unknown to me, and can't see how would
use it here.

> Excellent image (as always).... I am finishing a desert scene which I
> shall show here soon. Much cruder textures however than your finely
> realistic ones

   I cheated greatly there... ;) there is only one texture for the stones,
which is a "procedularized" picture of a pebbles bed. I scaled it really
big, and translated it randomly for each pebble, making the finish also
random for each one.

-- 
Jaime Vives Piqueres

http://www.ignorancia.org

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On 05/06/2010 05:29 PM, nemesis wrote:
> randomized proceduralized placement, randomized proceduralized mesh-based
> geometry, randomized proceduralized imagemap-based texturing (not
> necessarily in this one)... you're such a random procedural magician! :D
>

   I love rand()!!! I use it even for things as bizarre as finding the camera
placement! ;)

-- 
Jaime Vives Piqueres

http://www.ignorancia.org

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On 05/10/2010 09:26 AM, Thomas de Groot wrote:
> Just thinking: With the DoF, you may get away with a lesser number of
> spheres, or are they all concentrated in the sharp zone?

   No, I'm not that sharp: they are scattered evenly. And there is a real
difference in realism even on the blurred zones. Oh, and 3.7 managed to
parse all the scene in 29 seconds, so why bother? :)

-- 
Jaime Vives Piqueres

http://www.ignorancia.org

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Am 09.05.2010 17:41, schrieb Jaime Vives Piqueres:
> On 05/06/2010 11:30 AM, clipka wrote:
>> See <http://www.tc-rtc.co.uk/imagenewdisplay/stills/index207.html> for
>> some other approach at sand.
>
> Ok, after a painful move to the new AMD Phenom II x4, that took two days
> to complete, finally got the chance to try it out. I added 350,000 spheres
> and it still rendered in 4h! :)

Looking /really/ good now!

Yes, a neat QuadCore is fun with POV-Ray ;-)

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"Jaime Vives Piqueres" <jai### [at] ignoranciaorg> schreef in bericht 
news:4be7c030@news.povray.org...
> On 05/06/2010 03:49 PM, Thomas de Groot wrote:
>> Additionally, what you can use to good effect, is the prob() function.
>
>   prob()??? ...I've never heard of that function. In fact, the only thing 
> I
> can find is prod(), which was also unknown to me, and can't see how would
> use it here.

It is not described in the docs it seems... You can find the probability 
macro as the first one in rand.inc. I use it quite often to select between 
different plants for instance, or any selection of objects.

>
>> Excellent image (as always).... I am finishing a desert scene which I
>> shall show here soon. Much cruder textures however than your finely
>> realistic ones
>
>   I cheated greatly there... ;) there is only one texture for the stones,
> which is a "procedularized" picture of a pebbles bed. I scaled it really
> big, and translated it randomly for each pebble, making the finish also
> random for each one.

Great technique! I shall remember that.

Thomas

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On 05/10/2010 11:33 AM, Thomas de Groot wrote:
> It is not described in the docs it seems... You can find the probability 
> macro as the first one in rand.inc. I use it quite often to select between 
> different plants for instance, or any selection of objects.

ha ... new one on me as well! since you've used it, perhaps you could
come up with a sentence or two and i'll add it to the wiki docs

i'll watch this thread or you can put it over here:
http://wiki.povray.org/content/Documentation_Talk:Reference_Section_7.3

jim

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"Jim Holsenback" <jho### [at] povrayorg> schreef in bericht 
news:4be82250$1@news.povray.org...
> ha ... new one on me as well! since you've used it, perhaps you could
> come up with a sentence or two and i'll add it to the wiki docs
>
> i'll watch this thread or you can put it over here:
> http://wiki.povray.org/content/Documentation_Talk:Reference_Section_7.3
>

Well, you could maybe use something like this:

Prob(P, RS)
The probability macro returns true or false. P is the probability of 
returning true (value between 0 and 1) RS is a random number stream.
Example code:
//start code
//If you want a 40% chance of red objects amongst blue ones
#local ObjProb = Prob(0.4, r);
object {
  #if (ObjProb)
    RedObj
  #else
    BlueObj
  #end
  .....
}
//end code


Thomas

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On 05/11/2010 05:28 AM, Thomas de Groot wrote:
> Well, you could maybe use something like this:

haha ... I think WE ALL deserve a RTFM on this one ;-)

It was already there:
http://wiki.povray.org/content/Documentation:Reference_Section_7.3#Discrete_Distributions

In the unix docs it's in section:
3.7.11.2.3 Discrete Distributions

Jim

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"Jim Holsenback" <jho### [at] povrayorg> schreef in bericht 
news:4be91fcd$1@news.povray.org...
>
> haha ... I think WE ALL deserve a RTFM on this one ;-)
>
> It was already there:
>
http://wiki.povray.org/content/Documentation:Reference_Section_7.3#Discrete_Distributions
>
> In the unix docs it's in section:
> 3.7.11.2.3 Discrete Distributions
>

The thing is that in the unix docs, it does not appear in the Index....  so, 
I assumed...


Thomas

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On 05/11/2010 11:39 AM, Thomas de Groot wrote:
> it does not appear in the Index....

it was missing this tag needed for it to appear in the index listing:
<!--<indexentry primary "Prob">--->

Jim

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