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variable translucent AGS?
Posted: Fri Mar 30, 2012 5:30 pm
by JPMays
Does anyone know how to make (or have a good material to share) a translucent AGS? I don't want a frosted type glass, it needs to have the same reflectance as regular AGS.
Here's an example of what I want to achieve, but I made this with regular glass that takes way too long to clear.
There are four types of glass here - clear, 40, 60, & 80% opaque.
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 5:38 pm
by Half Life
Regular AGS works on simple layer opacity -- 12.5 is the default, but you can set it for any opacity you like.
"Clear" AGS is a bit more complex but may actually be more flexible for your needs.
Best,
Jason.
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 6:10 pm
by JPMays
My understanding of AGS is limited, so correct me if I'm wrong - it is a single layer, perfect mirror material, that you then lower its opacity to 12.5 - 15 so it looks like glass. I want to create a material like that to get the "glass" looking right, not too reflective, with the right color, but then maybe have another layer that I can adjust for the different opacities. Would that work?
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 6:39 pm
by Half Life
When you say "opacity" are you thinking to mimic tint? because that would be the same thing as just upping the reflection value in the wizard.
The only other type of glass opacity I can think of (beyond frosted) is SSS type additives to add color opacity (usually for stained glass).
Best,
Jason.
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 6:46 pm
by JPMays
I don't want an SSS, because that would increase rendering time even more (though it would achieve what I want). Basically I want several types of glass, that all have the same reflectivity - i.e. if seen at an angle they all would have the same reflections. However, when seen straight on, some would let less light pass through than others.
-clear: lets most light through - what you would expect from typical "clear" glass (which is not perfectly clear I know)
-40% opaque: lets in 60% of the light that clear glass does
-60% opaque: sim. as 40
-80% opaque: sim. as 40
What I did when I made my actual glass materials was to create a basic glass I liked, and make that 50% blended so it didn't mask out the lower layer. Then I added another layer below that was a sold gray color, and adjusted its opacity accordingly (40, 60, or 80).
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 7:21 pm
by Half Life
Well, by definition what you did before changed the reflectivity of the glass as it was only 50% or of it's real reflectivity -- but since you weren't bothered by the difference in effect before I'd say just do the same thing with AGS.
Best,
Jason.
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 7:23 pm
by JPMays
thats true, but what I meant is that that is consistent between all four types, so they all reflect the same.
Is it really as simple as creating (or modifying) a simple AGS, and then adding my variable opacity solid layer below?
Re: variable translucent AGS?
Posted: Fri Mar 30, 2012 7:25 pm
by Half Life
Well AGS is a unrealistic hack of the system that "kinda" looks like glass (but really resembles no known substance) -- so I'm not sure there is any wrong way to modify it
You might want to use additive mode to maintain the reflections more purely -- like this:
variableAGS.zip
Best,
Jason.
Re: variable translucent AGS?
Posted: Sat Mar 31, 2012 4:43 am
by rusteberg
JPMays, yes it really can be as simple as creating a simple AGS and then adding your variable opacity layer below it.
However, with this method you loose the "translucent" effect by replacing it with an "opaque" (opacity) effect.
There is another way of doing this in order to achieve what (i think) you are looking for.
Here is how you would set up the example Half Life posted (which there's nothing wrong with doing):
it would render to this:
Another option you could try would be this:
which would render (faster) to this:
in this case, the glass material is setup like what is shown below and the translucent shadow plane is a single layer material with an opacity set to transmit the amount of light your AGS material would produce.
Another option would be to combine the material above with the material Half Life posted as shown below if you wanted to retain the light reflecting off of the windows:
it would render to this:
Furthermore, you could add the variable opacity solid layer into the hidden from GI glass material for additional tweaking:
setup like so:

Re: variable translucent AGS?
Posted: Sat Mar 31, 2012 10:47 am
by Polyxo
Great thread.
Thanks a lot HalfLife and rusteberg!