Hello folks,

Ok, so I asked about this a while back but we couldn't seem to get anywhere. The community and its knowledge is growing all the time, so hopefully someone has just the trick to produce this kind of effect in PP2014!

Basically, I'm looking to create a 'frosted glass' effect on either a flat plane or a thin 'cube'. I managed to produce a render with Annie of 'kind of' the effect I was hoping for, but it's far from perfect and the techniques involved make it useless for things like frosted windows for interiour doors and such like.

I've posted a link to my piece on DA with the explanation of what I did. This kind of works for this particular sort of art, but I'm looking for an actual material to put onto windows, glasses and various other things in a Poser scene.

Perhaps BagginsBill has some ideas? ;)

Cheers folks,

Glen.

http://glen85.deviantart.com/art/Annette-Whiteout-453814831

Frosted glass

I can't help with the material - waiting to see what Snarly has to say on the subject - but regarding your concerns on the shadow:

If I've understood you correctly, your light source has a large area so it will naturally produce very blurred shadows for objects which aren't close to the 'frosted' screen. Although this isn't my area of expertise I don't imagine there's a way to change this - the renderer is doing the 'right' thing from a light physics point of view.

If this were my project I might experiment with a spotlight behind the figure, where I could adjust the shadow blur.

Quote - I can't help with the material - waiting to see what Snarly has to say on the subject

... it's all in the stickied EZMat thread

Thanks guys. Yeah, I tried different direct lights initially, but the shadows weren't blurring, they were just getting bigger or smaller depending on the placement of the objects. I tried it with two identical spheres, one close to the plane and one close to the light, but there was no difference in blur, which was odd. I put that much in the other thread but it seemed somewhat of a mystery.

SnarlyGribbly, that looks quite nice! I wonder if it would be possible to make the 'lumps' smaller without making the texture of the glass repetitive. Think sand blasted or etched, like the designs that are found on some beer glasses, it's much paler and has a much finer texture.

Quite a lot like this: http://hqwallbase.com/images/big/frosted_glass_chess_chess_pieces_glass_glass_art_wallpaper-13200.jpg

Frosted glass using fine-grained bump will not really cut it. It will have some of the character, but frosted glass has microscopic pits by the millions and bump maps can't get you there. (In theory they could, but in practice I've never been able to get Poser to do microscopic surface effects accurately with a bump map.)

The frosted glass is done better by taking an ordinary glass shader (with reflect and refract combined via Fresnel_Blend) and increasing the "Softness" on both the Reflect node and the Refract node. You will also have to increase the "Quality" parameters, as well as better render settings for min shading rate and pixel samples. You can have "fast" or "good", but not both. 

I have the quality pretty low here, so that I have a render to show with it made in the last few minutes.

That's awesome, Bagginsbill, thank you very much! I'll have a go with that!

So what is a blinn node, or is explaining that going to take forever? Still very novice to the material room but learning little bits all the while.

Also, I'd like to thank SnarlyGribbly for his EZ Metals shaders, I found them today and have made good use of some of them in my scene for Annie's home, same as I hope to do with this frosted glass.

Thanks folks, smashing!

Glen.

I was able to adjust my parameters and get this result, rendered in about 13 minutes, which I think is really quite good.

The first HSV is not doing anything as it is set to 1, 1, 1. If, however, you want to make the glass transmit a bit less, you can decrease the HSV Value below 1.

Awesome, that is good! So what would I adjust to make it look like white material, as you'd likely find in a photo studio? I'm thinking it will be a simple colour change or something but I'd be interested to know how you'd do it.

Thanks a million for that! :D

Here is basically the same shader, but simplified. (I don't make these shaders by hand - I have scripts to generate them. Today I added some logic to my scripts that tries to take advantage of the Poser Surface root node to add things up, instead of Color_Add nodes. 

What we have here is a mixture of some diffuse and some frosted refraction. There is no fixed rule about how much of either you should use. Just be aware that if you have two parallel surfaces, the effect is squared, compared to a single surface. So your numbers (Diffuse_Value, Refraction_Value) would need adjustment for different situations.

You can, of course, place any color you like into the Diffuse_Color - the glass will take on a tint toward that color, but still will show the colors of what is behind it as well.

The front grid is the glass, with clear smooth glass frames around 25 frosted cells. Twelve inches behind that is a hollow red grid - something for us to easily see how the closer objects will look through the glass as well as let us look far away at the background scenery.

The frosted cells use the shader I just posted.

Bottom row has no softness or blur. Top row has .5. In between rows have in-between values. 

Left to right has various combinations of diffuse value and refraction value. The left-most column is all refraction, 0 diffuse. The right-most column is .5 diffuse, .5 refraction. The columns in between interpolate those values.

Good job as usually :D

Absolutely brilliant stuff! So I take it I can increase the diffuse and refraction right up until it basically just turns into a white mass?

This could mean a return of Annie in Whiteout as a series instead of a one-off!

Thank you so much! :D

Oh, I'm sure someone was gonna ask sooner or later. smirk

I love that stained glass effect. :)

Very nice stuff!

Funny you said about stained glass, as I've just had a go at doing my own in Annie's bathroom window. Unfortunately, the whole thing gave me a BSOD and I haven't tried it since, but when I get a render out of it, I'll pop it up here. :)

Quote - Is it possible to create the shader to also colour the light as it comes through like in this photo?

No. When people talk about this they think it is caustics and even SM people talk about caustics occasionally. Since caustics are computationally difficult (and really not possible with Firefly) people forgive/dismiss it.

But this particular effect is not caustics. This is colored transparency (basically change the Poser transparency number into a color), and Poser could do it but it doesn't.

The effect could be achieved by using a spotlight with the same image as the window...

Also, what would I change to get the following effect in the render of Annie, please?

Glen.

N.B. I made this effect with shadows on a plain white square with Annie being set to not appear in the camera, so the shot is actually taken from behind her, but I'd like to have this effect through a square so that I can render it from the other side and have Annie visible in the camera. That way, I'm hoping I can create maps for the square to create 'holes' in the material, which I'm assuming will be done in the same general way as a trans map would be, with black, white and grey areas.

I'm always amazed at how many things I'm not interested in until I see posts like this.  Frosted Glass was something that I didn't care much about doing in Poser.  Now that I read this.  I'm all about the frosted glass and I don't even know what I would use it for. lol.  

Neat, I'll give this a shot, thanks Bagginsbill! You're definitely THE go-to guy for anything Poser material related; that goes without saying! :)

(Someone's bound to ask about wet/steamy glass, so it might as well be me...) All those saucy shower scenes would look much saucier with steamy glass and mirrors! I wonder if something similar to the soapy skin technique by EventMobil could be used on something like a figure's body parts, so that the water residue wasn't applied to areas of glass (shower screen) where the figure's body was touching/had touched? That would make for some very interesting renders!

Just thinking in text form. I don't really know how these things work, I'm just pleased when they do, lol! I come up with ideas, that's all I'm good for. :)

Glen.

glen, pixel samples 10 excessive.  is anti-aliasing feature which roughly defines gradient between figure and BG. in test renders, shading rate 0 also extreme.  both variables increase render time and CPU temp with no benefit.  suggest SR 0.5 and PS 4 to expedite.

ps. enjoy BB's stained glass diffuse discussion.  

Thank you, Nancy! I'll give those settings a tweak. :)