View topic - YafaRay materials

YafaRay materials

Post here questions about using YafaRay materials, texturing and procedural models.

Post Sun Jun 01, 2008 1:39 pm

Samo;
Sorry for the late reply, I just got back from out of town.

I'm not quite understand about what you said. When you say "Diffuse Color", does it refer to the Blender's Ref value under the Shaders tab? If so, here are my tests;


Diffuse Color = 1.0, Diffuse Reflection (in Yafaray export script window) = 0.4
Image

Diffuse Color = 0.4, Diffuse Reflection (in Yafaray export script window) = 0.4
Image

Diffuse Color = 0.4, Diffuse Reflection (in Yafaray export script window) = 1
Image

All three images are Glossy mat. with the same Diff. color and the same Glossy reflection value. Seems to me that Yafaray exporter ignores (or over-write) the Ref value under the Shaders tab. Because the first two looks the same.

Not sure if that's the point you tried to tell me. Please correct me if I'm misunderstood the whole point.
Cheers.

Pentium4 3.0 HT, 4 GB ram, Windows XP 32bit.
Blender 2.46, YafaRay 2.0.2
palawat
 
Posts: 55
Joined: Wed Jan 09, 2008 4:21 am
Location: Bangkok, TH

Post Mon Jun 02, 2008 7:29 pm

[edited with Bert's advice]

hum... I think you did not understand me. I was theorizing about the rule diffuse + specular = 1

in my examples I'm using only yaf(a)ray python User Interface settings.

The point I'm trying to make is that, in any material, total diffuse = diffuse color x diffuse reflection

In other words, the final diffuse value is the luminance (i.e. brightness) of the color x the diffuse scalar value. Diffuse reflection is fact only a scalar value

So theorically you can get a diffuse look by either or both using Diffuse color and/or diffuse reflection.

In my examples the first uses Diffuse color and the second diffuse reflection (yafaray settings), both have almost the same look.

if you have a diffuse color of 1.0 1.0 1.0 and a scalar of 0.5 you get the same result when you have 0.5 0.5 0.5 and 1.0

Since most of the people give a diffuse color to their materials, and later a value in diffuse reflection, then in fact that rule should be:

(diffuse color x diffuse reflection) + specular (glossy) reflection = 1

yaf(a)ray presevers the energy by itself, so if the sum is larger than 1, the diffuse value get lowered.
Last edited by Samo on Tue Jun 03, 2008 11:17 am, edited 1 time in total.
User avatar
Samo
 
Posts: 3105
Joined: Tue Dec 20, 2005 10:39 am
Location: Spain

Post Tue Jun 03, 2008 6:04 am

Now, I get it.

Thank you very much, Samo (and Bert), for the explanation. :D
Cheers.

Pentium4 3.0 HT, 4 GB ram, Windows XP 32bit.
Blender 2.46, YafaRay 2.0.2
palawat
 
Posts: 55
Joined: Wed Jan 09, 2008 4:21 am
Location: Bangkok, TH

Post Fri Jun 06, 2008 10:48 am

thanks Samo for the expertise,
so, is there a way how to modulate a roughness of surface by a texture - I mean the "exponent map" effect in this case?
Lets say I have a wooden floor that is polished more on one side, what texture channel is suitable here - glossy reflection map? I think that it would define only the amount of reflection (how much light gets reflected) of the surface at given point and not the glossiness of the reflection. am I right?
Lempour
 
Posts: 17
Joined: Fri Apr 25, 2008 6:49 pm

Post Sun Jun 08, 2008 1:14 pm

Lempour wrote:thanks Samo for the expertise,
so, is there a way how to modulate a roughness of surface by a texture - I mean the "exponent map" effect in this case?
Lets say I have a wooden floor that is polished more on one side, what texture channel is suitable here - glossy reflection map? I think that it would define only the amount of reflection (how much light gets reflected) of the surface at given point and not the glossiness of the reflection. am I right?


only glossy can be mapped at the moment, and it defines amount of reflection AFAIK, you can do it both or either mapping Glossy reflection and Glossy color. What can't be mapped is exponent value, so the glossyness is uniform
User avatar
Samo
 
Posts: 3105
Joined: Tue Dec 20, 2005 10:39 am
Location: Spain

Post Thu Jun 26, 2008 9:54 am

hi samo,

the rule of diffuse+specular = 1 seems not relevant to glossymat .
glossymat seems to internally lower diffuse when specular value is raised.so diffuse should be left unaltered.

test - constant diffuse(255,0,0),varying glossy value

Image
rusted
 
Posts: 86
Joined: Mon Apr 23, 2007 12:17 pm

Post Fri Jul 18, 2008 6:29 am

Is there a way I can use Image textures on an object that is a light source without vanishing (burning) all my textures?
User avatar
mookie
 
Posts: 228
Joined: Tue Sep 18, 2007 6:41 am
Location: Poland

Post Wed Oct 15, 2008 12:35 am

Is Bump (in glass material) the only method for making frosted glass in yafaray ?

thank you
daniel :wink:
User avatar
thuleke
 
Posts: 30
Joined: Tue May 22, 2007 3:08 am

Post Wed Oct 15, 2008 4:11 pm

thuleke wrote:Is Bump (in glass material) the only method for making frosted glass in yafaray ?

At the moment yes.
bert_b
 
Posts: 265
Joined: Sun Mar 23, 2008 11:31 pm

Post Sat Oct 18, 2008 3:38 am

I am trying to replicate a plastic material that is painted with a slight metalic speckle. Using the blender internal I would use a texture to create the metal fleck using the colour tab and or use another texture to create a bump for the slightly sparked finsh.. However, the kicker with this one is that the material has a clear coat. How can I get the metal fleck look and the clear coat (no texture) using yaf(a)ray? I was thinking about making a texture using the blender internal and then mapping that onto the material to get the metal fleck look... Is there an easier way? ..
pizzeater
 
Posts: 1
Joined: Fri Oct 17, 2008 1:18 am

Texture for specualr shader

Post Tue Oct 21, 2008 5:55 pm

Hey

is it possible to add a texture to the specular shader?

It seems procedural shaders only work with bump, and color
but not with specular shader.
...............................................
C l a a s E i c k e K u h n e n
Artist : Designer : Educator
User avatar
cekuhnen
 
Posts: 281
Joined: Mon Jan 10, 2005 10:00 pm

Re: Texture for specualr shader

Post Wed Oct 22, 2008 10:30 am

cekuhnen wrote:Hey

is it possible to add a texture to the specular shader?

It seems procedural shaders only work with bump, and color
but not with specular shader.


see here:

http://www.yafray.org/forum/viewtopic.php?p=8426#8426
User avatar
Samo
 
Posts: 3105
Joined: Tue Dec 20, 2005 10:39 am
Location: Spain

Post Wed Oct 22, 2008 12:47 pm

those topics must be collected in a sticky thread for doc. purposes... if are not subject of changes ...
funlw65
 
Posts: 36
Joined: Fri Oct 03, 2008 6:11 pm

Post Wed Oct 29, 2008 1:19 pm

Great Topic :)
Hopefully there will be gathered many more materials.

Can somebody provide another link to the 'material scene'?
Zshare does not work for me, i can't access the file.

thx
Melroc
 
Posts: 5
Joined: Thu Oct 23, 2008 1:30 pm

Post Wed Oct 29, 2008 2:46 pm

Reuploaded on Rapidshare

example scene for YAFARAY

http://rapidshare.com/files/158703267/e ... s.zip.html

YAFARAY guide (PDF)

http://rapidshare.com/files/158696532/y ... 3.pdf.html
Last edited by pepi74 on Wed Oct 29, 2008 7:26 pm, edited 1 time in total.
User avatar
pepi74
 
Posts: 67
Joined: Thu Oct 16, 2008 12:58 am

PreviousNext

Return to Materials and Texturing



Who is online

Users browsing this forum: No registered users and 10 guests

cron