Hello, I have a question: how to make a blurred reflection in Povray version
3.7?

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"Cossack " <nomail@nomail> wrote:
> Hello, I have a question: how to make a blurred reflection in Povray version
> 3.7?

The method I know of is here, under the heading: "Is blurred reflection possible
in POV-ray?"

https://wiki.povray.org/content/Knowledgebase:Language_Questions_and_Tips#Topic_13

It works by averaging multiple almost-identical textures, each with a
different 'normal', to create the blur.

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"Cossack " <nomail@nomail> wrote:
> Hello, I have a question: how to make a blurred reflection in Povray version
> 3.7?

Use a very scaled down normal and keep the "hight" of it relative big. Use a
patter like granite or noise like

ingo

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Le 2026-05-26 à 13:28, Cossack a écrit :
> Hello, I have a question: how to make a blurred reflection in Povray version
> 3.7?

Work with versions 3.3+.
Two ways :
1) Micro-normals. Use some normal, like granite, scaled very small. Need 
to use antialiasing to work.
2) Averaged normals. Apply many normals randomly displaced. Really slow 
down the render. You must avoid inter reflections between surfaces with 
blurred refection. Use no_image and no_reflection this way : One object 
with the averaged normals and the no_reflection attribute. Don't show in 
reflections.
A second identical object with micro-normals or just normal reflection 
instead of the averaged normals, and the no_image attribute. Not visible 
directly, but shows in reflections.

Micro-normals work best with some averaging. Normally, 5 to 10 instances 
are OK.
Averaged normals usually demand 200+ instances.

=====================================================

With version 3.8 and radiosity, you can get blurred metallic reflection 
using brilliance.
Need to add «brilliance on» in the radiosity block.
Need the surface to have a pretty high brilliance. Typically 100 to 1000.
This blurring seems to be similar to phong highlights : Higher value = 
more and sharper reflection.

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On 26/05/2026 23:28, Kenneth wrote:
> "Cossack " <nomail@nomail> wrote:
>> Hello, I have a question: how to make a blurred reflection in Povray version
>> 3.7?
> 
> The method I know of is here, under the heading: "Is blurred reflection possible
> in POV-ray?"
> 
> https://wiki.povray.org/content/Knowledgebase:Language_Questions_and_Tips#Topic_13
> 
> It works by averaging multiple almost-identical textures, each with a
> different 'normal', to create the blur.
> 

Thanks, Kenneth, for reminding us of this tip. I’d never tried it 
before, but you can get good results quickly with this method.

#declare BlurAmount = 0.15;
#declare BlurSamples = 40;

normal {
   wrinkles BlurAmount
   translate <rand(S),rand(S),rand(S)>/2
   scale 0.001
   }




-- 
kurtz le pirate
compagnie de la banquise

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kurtz le pirate <kur### [at] freefr> wrote:
> On 26/05/2026 23:28, Kenneth wrote:
> > "Cossack " <nomail@nomail> wrote:
> >> Hello, I have a question: how to make a blurred reflection in Povray version
> >> 3.7?
> >
> > The method I know of is here, under the heading: "Is blurred reflection possible
> > in POV-ray?"
> >
> > https://wiki.povray.org/content/Knowledgebase:Language_Questions_and_Tips#Topic_13
> >
> > It works by averaging multiple almost-identical textures, each with a
> > different 'normal', to create the blur.
> >
>

> before, but you can get good results quickly with this method.
>
> #declare BlurAmount = 0.15;
> #declare BlurSamples = 40;
>
> normal {
>    wrinkles BlurAmount
>    translate <rand(S),rand(S),rand(S)>/2
>    scale 0.001
>    }
>
>
>
>
> --
> kurtz le pirate
> compagnie de la banquise

It's a shame that I have a crappy phone, and my PC has passed on to a better
world.;]

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"Cossack " <nomail@nomail> wrote:
> Hello, I have a question: how to make a blurred reflection in Povray version
> 3.7?

This file contains macros that implement the solution that Kenneth referred to:
  https://github.com/CousinRicky/POV-RC3Metal/blob/main/rc3metal.inc

RC3Metal_Blur_t() is a naive implementation.  It's perfectly fine for a simple
object with no other reflective object in the scene, but it can bring your CPU
to its knees if there are mutual blurred reflections.

RC3Metal_Blur() uses the optimization that Alain described.

The argument t_Base is the reflective texture that you want to blur.

Note that if t_Base has a normal, the above macros will not work as expected.
Use macros RC3Metal_Normal_blur_t() or RC3Metal_Normal_blur() if you want a
blurred normal.

The entire library, including documentation and examples, can be downloaded at:
  https://github.com/CousinRicky/POV-RC3Metal

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kurtz le pirate <kur### [at] freefr> wrote:
> On 26/05/2026 23:28, Kenneth wrote:
> > "Cossack " <nomail@nomail> wrote:
> >> Hello, I have a question: how to make a blurred reflection in Povray version
> >> 3.7?
> >
> > The method I know of is here, under the heading: "Is blurred reflection possible
> > in POV-ray?"
> >
> > https://wiki.povray.org/content/Knowledgebase:Language_Questions_and_Tips#Topic_13
> >
> > It works by averaging multiple almost-identical textures, each with a
> > different 'normal', to create the blur.
> >
>

> before, but you can get good results quickly with this method.
>
> #declare BlurAmount = 0.15;
> #declare BlurSamples = 40;
>
> normal {
>    wrinkles BlurAmount
>    translate <rand(S),rand(S),rand(S)>/2
>    scale 0.001
>    }
>
>
>
>
> --
> kurtz le pirate
> compagnie de la banquise

I managed to learn this result with 3 samples

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Le 2026-05-30 à 23:47, Cousin Ricky a écrit :
> "Cossack " <nomail@nomail> wrote:
>> Hello, I have a question: how to make a blurred reflection in Povray version
>> 3.7?
> 
> This file contains macros that implement the solution that Kenneth referred to:
>    https://github.com/CousinRicky/POV-RC3Metal/blob/main/rc3metal.inc
> 
> RC3Metal_Blur_t() is a naive implementation.  It's perfectly fine for a simple
> object with no other reflective object in the scene, but it can bring your CPU
> to its knees if there are mutual blurred reflections.

How to avoid this problem :
1) Give the objects with the blurred reflection the no_reflection attribute.
2) Create a second version of the objects with just normal reflection, 
or the micro-normals based blurred reflection, and the no_image attribute.

> 
> RC3Metal_Blur() uses the optimization that Alain described.
> 
> The argument t_Base is the reflective texture that you want to blur.
> 
> Note that if t_Base has a normal, the above macros will not work as expected.
> Use macros RC3Metal_Normal_blur_t() or RC3Metal_Normal_blur() if you want a
> blurred normal.
> 
> The entire library, including documentation and examples, can be downloaded at:
>    https://github.com/CousinRicky/POV-RC3Metal
>

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