"Zeger Knaepen" <zeg### [at] studentkuleuvenacbe> schrieb im Newsbeitrag
news:3d6bde5e@news.povray.org...
> > > I was trying to do focalblur by averaging different renders earlier this
> day.  I
> > > came up with the following formula to scatter points inside a regular
> polygon:
> > >
> > >   #declare Seed=seed(whatever);
> > >   #declare angles=<insert number of angles here>;
> > >   #declare Rot=360*rand(Seed);
> > >   #declare X=pow(rand(Seed),.5);
> > >   #declare Rot2=Rot/(360/angles);
> > >   #declare fraqrot=Rot2-int(Rot2);
> > >   #declare fraqrot2=abs(fraqrot-.5);
> > >   #declare fraqrot3=pow(fraqrot2*2,.5);
> > >   #declare Location=vrotate(x*X*(.8+.2*fraqrot3),Rot*z);
> >
> > probably right....
> > but please compare these lines to the simple way of determing a single
point
> > in an rectangle concerning the time it takes to compute it ...
> >
> > ... and then take into account, that this has to been done multiple times
> > per pixel ... Maybe its ok to precompute ~2^10 such values and store them
> > in a table, so you can reuse them later ... but I'm not sure this will
help
> Yes, a rectangle, or a circle, will be faster, that's why you should have
the
> option to use a circle (or a rectangle, but I don't think that would give
> realistic results actually).
>
Hi,

why not just make a circular pattern by generating the Points like before
in a rectangular area and then testing  [x^2+y^2 > Radius] for the Point
to find out if it lies in the Circle. If the Condition is True, just generate
another Point until it's inside the Circle. This is a common and fast way to
get circular Points.

Greetings,
Thies

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> Hi,
>
> why not just make a circular pattern by generating the Points like before
> in a rectangular area and then testing  [x^2+y^2 > Radius] for the Point
> to find out if it lies in the Circle. If the Condition is True, just generate
> another Point until it's inside the Circle. This is a common and fast way to
> get circular Points.
Because in real life, it aren't perfect circles, but regular polygons.  So it
would be better if POV-Ray had an option to use regular polygons instead of
perfect circles.  That in combination with non-clipped focal blur, would allow
us to create realistic focal-blurred images.

cu!
--
camera{location-z*3}#macro G(b,e)b+(e-b)*(C/50)#end#macro L(b,e,k,l)#local C=0
;#while(C<50)sphere{G(b,e),.1pigment{rgb G(k,l)}finish{ambient 1}}#local C=C+1
;#end#end L(y-x,y,x,x+y)L(y,-x-y,x+y,y)L(-x-y,-y,y,y+z)L(-y,y,y+z,x+y)L(0,x+y,
<.5,1,.5>,x)L(0,x-y,<.5,1,.5>,x)               // ZK http://www.povplace.be.tf

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On Tue, 27 Aug 2002 21:10:30 +0200, "Gilles Tran" <git### [at] wanadoofr> wrote:
> There's a patch that implements this in POV-Ray that is currently being
> ported to 3.5 (it's under testing and not available yet).

Who does it ? French community again ?

ABX

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Interesting. Please keep us updated.

Rene

"Gilles Tran" <git### [at] wanadoofr> wrote in message
news:3d6bcead@news.povray.org...
>
> There's a patch that implements this in POV-Ray that is currently being
> ported to 3.5 (it's under testing and not available yet). From what I
heard
> it's faster that the regular focal_blur but I have not verified this
myself.

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j8pomug7b9itfc8scj99fka5vko9gdfnf3@4ax.com...
> On Tue, 27 Aug 2002 21:10:30 +0200, "Gilles Tran" <git### [at] wanadoofr>
wrote:
> > There's a patch that implements this in POV-Ray that is currently being
> > ported to 3.5 (it's under testing and not available yet).
>
> Who does it ? French community again ?

Yes, it's the patch by Mael (it also contains finish maps, HDRI support and
a whole lot of goodies). Unfortunately he has removed it from its location
but when he has something clean to show he'll tell us.

G.



--
**********************
http://www.oyonale.com
**********************
- Graphic experiments
- POV-Ray and Poser computer images
- Posters

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Gilles Tran wrote:
> 
> [...]
> 
> Yes, it's the patch by Mael (it also contains finish maps, HDRI support and
> a whole lot of goodies). Unfortunately he has removed it from its location
> but when he has something clean to show he'll tell us.

I really wonder why, most of the patches were already in a previous
version so i suppose they are quite well tested.  The projection pattern
looked really interesting.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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> I really wonder why, most of the patches were already in a previous
> version so i suppose they are quite well tested.

they were in a previous version but not really tested (and they still are not
:)
for those who want to try my current patched pov3.5 you can download this file
:
http://195.221.122.126/tmp/mlpov08.zip (1.7 Mo, windows exe only, compiled
with vc6 so probably slower than official version)
extract in your pov3.5 directory and run the mlpov.exe
for documentation (in french) click the mlpov button next to 'irtc site'
button

this version includes :
-aoi : new pattern , angle between incident ray and normal
-projection : new pattern, projection of an object
-shadow_pigment : to colorize shadows
-bokeh_pigment : for a customizable focal blur
-synthese : to create a new image_map from a sample image
-finish maps : to specify a function for finish parameters

don't forget to add
#version unofficial mlpov 0.8;
in your scene to test the patches.

M

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Mael wrote:
> 
> > I really wonder why, most of the patches were already in a previous
> > version so i suppose they are quite well tested.
> 
> they were in a previous version but not really tested (and they still are not
> :)
> for those who want to try my current patched pov3.5 you can download this file
> :
> http://195.221.122.126/tmp/mlpov08.zip (1.7 Mo, windows exe only, compiled
> with vc6 so probably slower than official version)
> extract in your pov3.5 directory and run the mlpov.exe
> for documentation (in french) click the mlpov button next to 'irtc site'
> button
> [...]

I have already downloaded this, but it would be much better if i was able
to use it on my linux box.  Also if you supply the source code it would be
likely that possible problems with the implementation are discovered in
case you don't have the time to test it in detail.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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> I have already downloaded this, but it would be much better if i was able
> to use it on my linux box.  Also if you supply the source code it would be
> likely that possible problems with the implementation are discovered in
> case you don't have the time to test it in detail.

i'm still doing some experimentations with the code, but may be later i will
try to compile a version for linux
you can download the modified sources here
http://195.221.122.126/tmp/sources08.zip
(if you're not too afraid to look at my ugly code :)

M

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in news:3d6cc1ac$1@news.povray.org Mael wrote:

> -synthese : to create a new image_map from a sample image
> 

Mael,

Thanks for the patch, I'm especialy facinated with the sythese and 
ofcourse I want always more. Would it be possible to use that kind of 
algorithem in 3D-space? Randomly picking small cubes from a unit cube 
and build a new pattern from there, in SDL something like:

pigment {
    	bozo
    	warp {synthese, BlockSizeVector, RandomStream}
}


Ingo

p.s. Good documentation! 
Would have been even nicer if it was in dutch ;)

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