Beer glass scene creation
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# 1 25-10-2011 , 07:06 PM
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Join Date: Oct 2011
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glass and shadows problem

I've been having some issues with lighting a large scene I'm working on so I decided to make a small "lighting model" and work it out there.

Scene:
  • I have a stained glass window with light coming through it.
  • I also have a clear glass window with a sphere behind it. i made a border to catch light and cast shadows.
  • I have two spot lights with ray trace shadows turned on. one pinkish throught the Stained glass and one greenish over the sphere. colors are just to make them easy to discern.

shaders:
  • my stained glass shader is a mia_material with PSD file node connected to both the diffuse color (mostly so I can see it) and the refraction color node with transparency turn up to 1
  • (see picture)
  • my clear glass is a mia_material preset thin glass - nothing changed from stock.
  • everything else is default lambert1.


Problem:

As you can see from my render, the stained glass is casting great stained glass shadows.
And the clear glass window is transparent.

Shadows are passing through the clear glass
--- you can see the stainglass shadow after it goes through the clear glass and you can see the green spot shadow after it has gone through the clear glass.

BUT the shadows ( both the Stained glass and the green spotlight) are not visible THROUGH the clear glass.
the sphere is white where it should have both stained glass and green light shadows. And the ground plain also has no shadows cast when looking through the clear glass.



What am I doing wrong?

Is there a better way to make glass then the Mia_material?

render:
user added image

Stained glass shader:
user added image

clear glass shader:
user added image

# 2 25-10-2011 , 07:46 PM
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It's not the the material, its happening because the light's ray depth limit is too low. That would be under the light's raytrace shadow settings.


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# 3 25-10-2011 , 07:58 PM
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I'll try that

# 4 25-10-2011 , 08:30 PM
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Ok..

so that worked for the green spot (If someone wants to explain way I would much appreciate it).
It worked equally as well with 2 or 3 or 6 ray depth limit... so i figure I should keep it low to keep rendertime down.
Thanks for that GecT!





original ray depth limit 1:
no through glass shadows
user added image

fixed ray depth limit 3:
shadows are fine for the lambert1 polygons - but the stainedglass shader still no shadow.
When the clear glass is hidden, you can see stained glass refraction on the sphere and floor - but even with ray depth up, you can't see it through the glass.
But it didn't work for the stained glass COLOR... it worked for the window frame. you can see that on the floor.
Actually the polygon that has the stained glass is shadowed through the glass - just no color refraction
Any ideas why?
Color is from the file attached to the refraction node
user added image

Glass hidden:

here you can see color shadow on sphere and floor
user added image

# 5 25-10-2011 , 09:52 PM
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It seems to be your render settings, you should check the raytracing section under the quality tab, it controls the overall limit for calculations of reflection/refraction/shadow tracing.


- Genny
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# 6 04-05-2014 , 02:47 PM
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Hi all,
I created nurbs sphere and assigned lambert to it. In Create PSD Network Options, I've chosen three attributes and they appear in selected attributes section. But when I press create button following message appears: // Error: Invalid call to "filetest". Check number and types of arguments expected by the procedure. I restored default settings, but it was in vain. So, I would appreciate some help on this user added image

# 7 04-05-2014 , 08:53 PM
Gen's Avatar
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This is an unrelated thread, please make one for this topic and better describe your problem.


- Genny
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# 8 04-03-2015 , 10:42 PM
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Join Date: Apr 2014
Posts: 21

glass won't cast shadows

Hello everybody,

I have I problem with my rendering my scene. In my scene I have two separate objects, a wall and wooden window. What I would like is to be able to see the light passing through the window and the shadow has the shape of a window. For that I placed point and spot behind the window. In AE of spot light I turned on ray trace shadows and set light radius to 2, shadow rays 40 and ray depth limit 4. In mental ray settings I anabled raytracing and set reflaction, refraction and max trace depth to 1. For the wood I created a 3d wood texture and assign it to the faces where I want wood to be and I assign mia material to the faces where there is glass. And when I render I can't see the shadow of a window. Beside the two lights I also have Physical Sun and Sky enabled. So I would very much appreciate help on this user added image

Attached Files
File Type: zip Scene_render.zip (974.9 KB, 242 views)
# 9 05-03-2015 , 08:55 AM
Gen's Avatar
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That is a zip file containing only a jpeg image, there is no Maya scene file.


- Genny
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