POV-Ray : Newsgroups : povray.general : <no subject> : Re: <no subject> Server Time
29 Jul 2024 18:26:26 EDT (-0400)
  Re: <no subject>  
From: Alain
Date: 10 Dec 2010 12:22:16
Message: <4d0261c8@news.povray.org>

> Hi,
>
> I try to render a room using Povray v3.6.1.
>
> I have some issues remaining about rendering with and without radiosity.
>
> I included 2 pov files one with, one without radiosity. Of course I get 2
> different results. Which is nice but just a few minor(maybe major) glitches
> remain to achieve more of povray's true potential.
>
> My questions are
>
> in sample Without radiosity-----
>
> 1- the wall to the right is dark, how can this be corrected? I tried using
>     shadowless keyword, this caused more problems eg. taking phong and shineness
>     away, leaving a matt and dull looking picture. Without shadowless some areas
>     remain in the dark. Should I use more than one light?

You may need more lights.
Shadowless light_source effectively don't cause any highlight. This is 
by desing. A shadowless light purpose is to act as a fill light, not as 
the main illumination.

To improve your scene, you should take a look at fading lights.
You enable it by adding: fade_power 2 fade_distance Some_Distance
When rendering an inside scene, it can realy improve the result.

>
> 2- the sink could be made look more metallic, how can this be achieved? Is my
>     usage of METAL5.jpg correct for this purpose? I want metals to look like
>     metals, not grayish. Like the metals I see in Jaime's renderings.

I don't think that any image_map is a viable solution to make any 
surface look metallic. No image_map can include the correct reflections.
Your code:
//begin SINK
#include "evye_22_POV_geom.inc"union{
#declare evye_223_size = max_extent(evye_22_) - min_extent(evye_22_);
#declare evye_223 = object {evye_22_ translate -min_extent(evye_22_) 
scale <1/evye_223_size.x, 1/evye_223_size.y, 1/evye_223_size.z> scale 
<60,25,40>}
object { evye_223 translate -x * 60 pigment {uv_mapping image_map {jpeg 
"METAL5.jpg"}scale 1 }
finish {phong 1 ambient 0.6 reflection 0.08}}
  rotate y * 0 rotate x * 0 rotate z * 0 translate <-213.5,64.5,152.5>}
//end SINK

You have a tyni amount of reflection and a huge ambient. Reduce the 
ambient to less than 0.1 and increase the reflection in the 0.6..0.95 range.
Adjust the phong value and use phong_size to get satisfying highlight. 
The default phong_size probably gives highlights that are to broad. 
Start round 200 and you probably need to go up from there.
ADD the metallic keyword.
You may remove the image_map and replace it with a plain pigment. 
Anyway, metal5.jpg is essentialy monochrome.

>
>
> in sample with radiosity-------
>
> walls look better, how can I correct the rest of these isuues?
>
> 1- sink still is not metallic
> 2- the painting on the wall looks like it lost some of its shininess or
>     ambience value same maybe true for cabinet doors since they use jpegs too.
For the radiosity, you should remove any ambient component from your finish.
For the finishes that don't include ambient, you should add:
#default{finish{ambient 0}} early in the scene.

The picture on the wall seems to have to much reflection.

If you use high ambient objects to illuminate your radiosity scene, 
those will NOT cause any highlight, only a light_source can do that.
Keep the light(s) or add some reflection to your shiny surfaces.


>
> I appreciate any help, I am really stuck on these for some time. I hope I was
> able to explain what I need, Like everyone else I want the best result Povray
> can offer with the materials I use.
> Thanks  a lot.
>
> here you can find the relevant files
> http://www.kitchendesigned.com/tmp/render_settings.zip
>
>
>
>

You can use #if(Use_Rad)...#else...#end and #declare Use_Rad = on; and 
#declare Use_Rad = off; to turn radiosity on and off.
That way, you only need a single scene file and don't need to copy your 
changes from one file to the other. In the long run, you'll simplify 
tour task.

Remember that any texture with an ambient different than zero will shed 
light on it's surrounding when you use radiosity.

Nobody can do a test render as you don't include some of the images needed.
There are also asome missing inc file:
stdinc.inc
model_101_POV_geom.inc
k_model_1_POV_geom.inc and possibly some others...
Wall_Texture.jpg

Another thing:
It's a bad practice to use full paths in your scene, as even if we have 
all the needed files, we don't have them in your path structure...
I may have the krem.jpg file, but not in:
"D:\\OPTIMA\\optima\\bin\\v2\\Textures\\ODA\\DUVAR\\krem.jpg"



Alain


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