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Problem with milk and glass
Posted: Sun Mar 11, 2007 5:40 am
by mrCarnivore
I'm trying to render a glass of milk since it seems like these are kind of in nowadays.
I would like to achieve a result like this:
http://www2.indigorenderer.com/joomla/f ... light=milk
But I have some problems: I followed the modeling instructions for fluid in a glass from here:
http://www2.indigorenderer.com/joomla/f ... .php?t=637
And I used the milk material from here:
http://www2.indigorenderer.com/joomla/f ... 88eb0#9018
The glass material I use is this:
Code: Select all
<medium>
<name>GlassMedium</name>
<precedence>10</precedence>
<basic>
<ior>1.50</ior>
<cauchy_b_coeff>0.0</cauchy_b_coeff>
<absorption_coefficient_spectrum>
<rgb>
<rgb>0.5 0.5 0.5</rgb>
</rgb>
</absorption_coefficient_spectrum>
</basic>
</medium>
<material>
<name>GlassMaterial</name>
<specular>
<transparent>true</transparent>
<internal_medium_name>GlassMedium</internal_medium_name>
</specular>
</material>
My problem is this: The bottom of the glass looks way too white which is very unrealistic. Also the milk is just too white...
But have a look yourself:
Posted: Sun Mar 11, 2007 5:57 am
by neepneep
How big is your model in blender?
Posted: Sun Mar 11, 2007 6:19 am
by mrCarnivore
When I press N in blender, the dimensions of the left glass are:
DimX = 0.20
DimY = 0.20
DimZ = 0.34
so it seems to be 20 cm long doesnt it? shall I reduce the size?
EDIT: The result doesn't really change when I reduce the size to DimX = 0.08..
Posted: Mon Mar 12, 2007 6:26 pm
by OnoSendai
Make sure the precedence of the glass medium is higher than that of the milk medium.
Posted: Mon Mar 12, 2007 9:00 pm
by 8bstudio
Try to use for the glass these settings:
Code: Select all
<medium>
<name>GlassMedium</name>
<precedence>10</precedence>
<basic>
<ior>1.50</ior>
<cauchy_b_coeff>0.0</cauchy_b_coeff>
<absorption_coefficient_spectrum>
<rgb>
<rgb>0.0 0.0 0.0</rgb>
</rgb>
</absorption_coefficient_spectrum>
</basic>
</medium>
Posted: Mon Mar 12, 2007 9:17 pm
by mrCarnivore
@OnoSendai: With higher you mean lower numer, right? So the glass medium is supposed to have a lower precedence number than milk?
@8bstudio: I think making the glass even whiter would be counterproductive, wouldn't it?
Posted: Mon Mar 12, 2007 9:27 pm
by OnoSendai
heh, no, when i say higher, i mean a higher value.
Yes, i know this contradicts the CS convention, but meh.
nik
Posted: Mon Mar 12, 2007 9:29 pm
by 8bstudio
mrCarnivore wrote:I think making the glass even whiter would be counterproductive, wouldn't it?
I saw in many post that completly transparent glass have rgb absorption coefficient = 0 0 0. I you use a rgb 0.5 0.5 0.5 maybe is grey glass!
In my test for glass with rgb 0 0 0 normaly I get good result! Try to see my last post for example
http://www2.indigorenderer.com/joomla/f ... 2&start=30
You can try!
Posted: Mon Mar 12, 2007 9:34 pm
by OnoSendai
absorption 0.5 0.5 0.5 is very slight absorption (mean path length on the order of 2m)
Posted: Mon Mar 12, 2007 9:43 pm
by 8bstudio
Maybe I wrong with glass rgb = 0 0 0 because with Indigo v0.6 I used those!
I try me too with 0.5 0.5 0.5!
Posted: Mon Mar 12, 2007 9:50 pm
by OnoSendai
The units changed from Indigo 0.6 to 0.7.
The units of absorption changed from mm^-1 to m^-1
Posted: Mon Mar 12, 2007 9:54 pm
by mrCarnivore
Thx for the help. Hope I'm seeing better results with the higher precedecy value.