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Not seeing reflection/shadow in glass


Christiaan

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The "Edge Color" (When you look along a Material Face) in Glass Shader should be White = 100 %.

Black will deactivate the Reflection.

 

Default in VW for Center Color is Black.

Which again means 0% Reflection when you look perpendicular to a Face.

Which is the situation for an orthogonal Elevation View !

But That is wrong.

For Glass it should be the typical Reflection amount of most Dielctric Materials.

Which is about 5-8 %. So you should apply a dark Grey color with 5-8% white

for your Center Color.

That is what you would also use for a Mirror or Plastic Shader in Reflection Channel.

 

As you have a orthogonal View, which doesn't exist in reality either (= infinite Focal Length)

it may be pretty ok to crank up the Center Color even more towards White,

like a brighter dark gray with 20-40 % White = 20-40 % Reflection.

So that it looks more "right" or pleasing.

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For orthagonal views i use a fake glass material. The glass shader only works in a perspective view as zoomer mentioned. Use a dark grey color, make it a little glossy with the mirror shader, make sure there are some objects to mirror behind the view (trees other buildings etc.) Reflections from hdri backgrounds don't work too because of the orthagonal view. When you want the window to reflect clouds, you have to fake them with a cloudy noise-shader as color. Now make the material a little transparent so you see some of the interior. This makes it look a little more like glass. The advantage of this method is that you get real shadows on the glass, which is what you want in facades, but is not what it looks in reality.

345390908_FassadeGlas.jpg.4ab62abfdadfcacc8edb8da828addf41.thumb.jpg.1bd53e3acc3a986efbd2e5e30eebb14b.jpg

Now only use this material in orthagonal views by overwriting the material in the class settings of your glass in the viewport.

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  • 3 weeks later...

Thanks for everyone's input on this. Slowly getting there.

 

On 11/19/2018 at 11:35 AM, herbieherb said:

For orthagonal views i use a fake glass material. Use a dark grey color, make it a little glossy with the mirror shader ... Now make the material a little transparent so you see some of the interior.

 

How is this different from a typical glass texture? Do you mean you use the Plain or Color transparency shader instead of the Glass one?

Edited by Christiaan
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I've attached a test file if anybody fancies a go. I'm making progress but haven't managed to produce shadows of any substance. I'm trying to achieve the following:

  • darkish windows
  • good reflections
  • shadows

It's that last one that's really difficult. I could manually add them in the Annotations Layer but would love manage this in the render if possible.

 

Here's a couple of examples. One with lightish windows and one with darker windows, but neither with any shadows.

 

1019794005_Screenshot2018-12-09at15_54_02.thumb.png.1a6f90a22f050d5ec368beff86c25b17.png

 

290410225_Screenshot2018-12-09at15_54_07.thumb.png.dbe6f5009fe59f153c2fda5be7fb572c.png

 

 

example.vwx.zip

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On 12/7/2018 at 9:53 PM, Christiaan said:

How is this different from a typical glass texture?

 

Here is a description of the material above:

 

As color i use a noise turbulence shader to imitate a cloudy reflection.

grafik.thumb.png.a3b60c54b31d1275797824dcbbeacb47.png

 

For the reflection of trees and stuff behind the cutting plane i use a common mirror shader:

grafik.thumb.png.7ead22f78003997d7cf953f6ab74e8c9.png

 

And finally there is a transparency-shader with about 75% transparency.

grafik.thumb.png.9bedfe4a0981b32118de0050b9a782da.png

 

Finally adjust the size of the clouds by the texture-size and activate the shadows for the material.

grafik.thumb.png.b692f5d918c807e8fdc7c6e435a1bdfe.png

 

In the settings of the section activate the shadows of objects behind the cutting-plane. Else you don't see any reflections of trees and stuff behind the cutting-plane.

grafik.thumb.png.edc87e40618833101e938406ebc48f2d.png

 

The glass shader doesn't work at all in an orthagonal view because it's math is based on the angle that you look at it.

Edited by herbieherb
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I tried to make an example for you but it seems that the option Cast Shadows of Objects Removed by Section doesn't work atm. So you can't see any reflections. But the sample has a glass material with transparency, cloudy look and shadows. And as soon as the bug is fixed it shoul'd also show reflections.

 

The file attached is a VW2017 file because this is the last version when the reflections did work. When you convert it to 2018 or 2019 the reflections disappear 😕

 

This is how it shoul'd look like:

glas.thumb.jpg.1635afb764c1ed8a1c117a33c273efee.jpg

 

glass.vwx

Edited by herbieherb
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21 hours ago, herbieherb said:

The file attached is a VW2017 file because this is the last version when the reflections did work. 😕

 

The German support indicated that it is a bug and reported it. Cast Shadows of Objects Removed by Section did'nt work for more than two years and no one noticed. 🙃

btw: very nice result @Christiaan

Edited by herbieherb
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