PDA

View Full Version : Control the transparent of dielectric material?


ghostlake114
11-25-2005, 08:18 AM
This is my test pic
http://i35.photobucket.com/albums/d152/ghostlake114/nt.jpg
---
As you see, both of glass here I use dielectric material ... But I can not see the transparent throght the glass :( ... How could I control the transparent of dielectric... I try a lot but seem no parameter like that :(...
--
Meanwhile, the bottle use the same shader with them but it has transparency.. :banghead: :banghead: :banghead:

MSB
11-25-2005, 01:34 PM
there's no transperent slider for it......its about how the object is obsorbing the light....and its very size dependent...if i were you i would work with simple scene and try to understand how the dielectirc works.

hope that helps...

ghostlake114
11-25-2005, 03:18 PM
So, are there any way that we can control transparency . if there is no such slider...so It mean there are some trick here ?
---

floze
11-25-2005, 03:47 PM
So, are there any way that we can control transparency . if there is no such slider...so It mean there are some trick here ?
---
The trick is called Beer's law. It means the transparency is dependant on how far light travels in the medium. It's simply applied by the color you apply for your dielectric - an HSV value of 1.0 would mean no light is absorbed at all. The lower the value (default is 0.98) the more light gets absorbed based on Beer's law. And since this law is scale dependant, note that this all is dependant on your scene's scale. This means the larger you built your scene (relative to a real world scale), the higher - closer to 1.0 - the HSV value for your dielectric's color should be. This also applies to the l_glass shader btw.

http://en.wikipedia.org/wiki/Beer's_law

ghostlake114
11-26-2005, 12:38 AM
Thanks a lot for reply, floze
---
I have played with HSV color of glass, change the V parameter many time and the result:
http://i35.photobucket.com/albums/d152/ghostlake114/0.jpg
V= 0.1
http://i35.photobucket.com/albums/d152/ghostlake114/05.jpg
V= 0.5
http://i35.photobucket.com/albums/d152/ghostlake114/07.jpg
V=0.7
http://i35.photobucket.com/albums/d152/ghostlake114/09.jpg
V=0.9
---------------------

ghostlake114
11-26-2005, 12:40 AM
http://i35.photobucket.com/albums/d152/ghostlake114/098.jpg
V=0.98
http://i35.photobucket.com/albums/d152/ghostlake114/0995.jpg
V=0.995
http://i35.photobucket.com/albums/d152/ghostlake114/1.jpg
V=1
http://i35.photobucket.com/albums/d152/ghostlake114/10.jpg
V=10
----
Seem HSV control the way it absorb light but It have nothing to do with transparency :( :cry: :cry: :cry:
----
I will post my scene so If you want, you can try to set the glass become transparent... :deal: :deal:
--
http://www.3dvn.com/ghostlake114/test_nt_glass.mb

e'lan
11-26-2005, 05:09 AM
I think your problem is not the amount of the transparency but object itself being not tranparent. I checked your scene file and your normals for the cube are pointing in the wrong direction, reverse them, normals should be outward facing. and clean up the model for better output.

- Vimal

ghostlake114
11-26-2005, 06:37 AM
Great..thanks alot...now It get transparent... The construct of model also normal vector decide how a surface will be when get a shader :)
----
However, for a mistake, I know how to make a real mirror :bounce: :bounce: :thumbsup:
---
This is my test with 0.1 and 0.98 V when rebuilt the glass with only one box
---
http://i35.photobucket.com/albums/d152/ghostlake114/glass2.jpg
V = 0.1
----
http://i35.photobucket.com/albums/d152/ghostlake114/glass1.jpg
V = 0.98
----
Hope this thread can also help someone searching for a way to make glass :)

CGTalk Moderation
11-26-2005, 06:37 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.