strange rendering of thin tinted glass

[bioman666]

Involved versions: SU 7.1.6860 / SKindigo 2.2.9 / Indigo 2.2.12

When I try to render a thin tinted glass layer (50mm thick for 8000*8000mm area), I get this.

I've tried specular (simple) and specular + SSS (this was my original choice, to get that milk effect) but the latter makes Indigo compute for ages to build the scene (many minutes, up to an hour before it gets into the rendering part) and it turns into something black and sparkling, which is not what i expected...

Thin glass material type is the only one that give me some translucency, but there is almost no tuning possibility.

Have you any idea on why i get this ?

[fenerolina]

Did you checked normals? (correct position of model's faces)

[galinette]

I get that times to times with sketchup.

Try:
- Flip normals of your object, then re-apply the material, then render
- Re-do the previous step another time
- Check that there is some space (try 1mm) between the object's bottom and the floor.
- Try a linked IGM instead of a material defined in Skindigo. The absorption parameter of skindigo is sometimes bugged.

Etienne

[Pibuz]

Hi Bioman666.
First of all, to get a tinted glass you don't need to use SSS: I suggest you DO NOT, instead. Calculating SSS is very heavy, and for plain coloured glass you don't need it. You have to simply set your material type to SPECULAR, and have the attention to give your SU material a slightly coloured shade, generally blueish-greenish. The amount of colour which will be absobed by the geometry is controlled by the opacity slider. Try light colours and an opacity of 10, you should get tinted glass, if your panel isn't too thick. If it is, the amount of colour absorbed will be higher, so you'll get a darker glass: then try to lower the opacity value of SU material.

And always check your normals: be sure you applied your SU glass mat to your white faces (facing outside).

Post the new results please! This should help other new users!

[bioman666]

Ok thanks for the leads, I've tried to reverse all faces and apply material again, and my thin layer disapeared...

Then I re-reversed the faces and i got my problem right the way it was: black.

@ Galinette: linked IGM gave me the render 3.png image, with the same black thin layer issue.

@ Pizbull: I draw a simple rectangle, pulled it up 50mm, selected all faces (CRTL+A, all faces were white), and applied the material (specular, see screen caption)... the render was empty. I'm getting lost !

[Whaat]

Hi,

Use SketchUp monochrome face style and make sure that the front faces are pointing 'out'. I think the problem might be your precedence setting. It is set to '1' which I think is the same as the surrounding air. The glass needs to displace the air so you need to set your precedence higher than 1.

Also, try changing your 'Surface Color' setting to 'None'. Surface color is a new feature and there may still be some bugs lurking with it.

[fenerolina]

In Sketchup:
view/toolbars/face styles:(look at the picture)
click the last cube on the right, it allows you to see which face has to be reversed or not: Blued faces are wrong, wright faces are white. Once you have all the faces white, apply the material.

my thin layer disapeared...

It desapears because you are trying to take a picture of a thin glass in a total empty space...

[Pibuz]

Done a little test scene, which I attach.
Just match the differences between your scene and mine.

Hope it helps!

[bioman666]

(I now realize I haven't even said "Hi" in my first message... All my apologies and Hi to you all !)

@ Pibuz + Fenerolina: the background was obviously missing.

But if I look from under i got the transparency, then i loose it when the object is looked from above...

[fenerolina]

Hi,
I checked your model and there is a little caos in there. I'm not sure what are you trying to do.