Indigo Renderer Forum

This is a test release so that I can get some feedback regarding the new material editor UI and the new material types that I've hacked up.
To create a diffuse transmitter material, set the type to "Diffuse" and then use the opacity slider to change the relative amount of transmittance and reflectance.
The Thin Glass material will export as a Blend between a null material and a high IOR phong material. Choosing the material will set the Sketchup opacity to 20 (sets the blend factor to 0.2). The material is not meant to have thickness. It has barely been tested so let me know what you think of it. I will post a sample render of it later. I don't know if it renders any faster than normal glass but at least it gives decent results without the need to have thickness.
To select the material you want to edit, click on it in the paint bucket or select an object with that material and press your material editor short-cut key (I suggest using an Alt or Control combination so that you don't accidentally change your material name).

#Version 0.8 beta1

#Added: application and material observers to determine the current selected material in the Paint Bucket
#Changed: combined material browser with material editor
#Changed: render setting 'bidirectional' to 'tracing method' to allow selection of more methods including hybrid
#Added: support for diffuse transmitter material. Change relative amount of reflectance and transmittance with the Sketchup opacity slider
#Added: Thin Glass material type

I'm positive there are lots of bugs lurking so go easy on me....

Whaat

Hehe you're trying to make an 'architectural-glass' material aren't you

Blending a high IOR phong and a null mat won't give very realistic results, I'm afraid

It will look like a mirror, that is semi invisible.
But I'd like to see test-images none the less
Maybe, diffusetransmitter + phong is way better, as it also can have colour dunno.

SORRY..BUT WHAT IS IT?IT'S PLUG IN?
FILIPPO

I just got an idea

Ono: how hard would it be, to add a "colour to transparency"-filter, like in the GIMP (maybe, Photoshop also has such a thing, but I didn't find yet) low IoR surfaces look very dark. If you can filter black out, you'd get a more or less correct thinglass
1.5-IoR-high-Exponent-pure-white-phong-with-black-to-transparent-filtering. would that be possible?

OnoSendai wrote: Blending a high IOR phong and a null mat won't give very realistic results, I'm afraid

I'm actually surprised about how realistic my test results actually are. Of course, this material would primarily be used for plane glass windows which, for all intents and purposes, are not much different than a "semi-invisible mirror"
What do you think of the tests?

Whaat

The problem is is that it doesn't follow Frensel's equations - higher reflectivity at grazing angles.

not bad... but a "black-to-transparent" would be even better...
All the darkening would change to transparency.
Then, you'd get "glass" without "caustics".
--> basically JUST an invisible thing, that has few reflections, to get visible...

I could simulate that, I guess... let's see..

also the things behind the glass wall wont look different, by IoR.

I'll make a quick test, mom

OnoSendai wrote:The problem is is that it doesn't follow Frensel's equations - higher reflectivity at grazing angles.

That's true, it doesn't account for Fresnel effects. However, you can work around this just by changing the blend factor. For example, if your scene has a group of windows that are being viewed at near grazing angle, you could change the blend factor to 0.6 (Sketchup opacity to 60) or even higher to give higher reflection (more Phong, less Null). For windows that are being viewed normal to the plane you could use a different Thin Glass material with a blend factor of 0.1 or 0.2.
Like I said, this material would only be useful for plane glass windows. It might help fill the void of a true Architectural glass material for the time being....

...looks good whaat, but how about the render times?

ok... I did a test now, but it has three problems:
1) It's postprocess and I really can't use the lasso tool.
2) It's post process, so I wasn't able to find the right way to blend it.
2a) You can't really see the reflection part :S
3) It's post process, so the shadows on the other side of the mirror don't show up. They should come through the transparent part.

That's why I also put in the two original renders and the modified version of the first render (that one with mirror)

Sorry, Kram, but I don't know what you are trying to show. I don't see anything that resembles a realistic glass material (which is the main topic of discussion)

I know...
My problem is, that my skills in both PS and GIMP aren't too good, otherwise, I could show much better, what I mean.

Ok... I'll try, to tell you, how it's supposed to be:

pic 1 (from top to bottom) is the pure render without the mirror.
pic 3 is the pure render WITh mirror.
pic 2 is the same pic as 3, but the mirror part has removed blacks (which has two issues: a) I had to use the lasso in Gimp, b) as it's not a pre process, but a post process, it removed ALL the dark parts, even where it would have been required)
pic 4 is the very bad result of not knowing, how to blend correct.
But if you look carefully, you can see, that there is a brightness difference in the mirror part...


Ok, I found a way, to at least DESCRIPE, what I want:

look at the thinglassphere: it's partly milky. If there was a way, to filter the colour of the specular, to be "clear", two things would fall away: the milky appearance and the alpha blend.
It so to say would be a specular transparent with these limitations:
no caustics
no thickness (actually as supposed to)
no frenesel
no long time to wait (what a limitation, lol)

this is one limit less, that you have: yours also is not perfectly clear...
not really important, but I guess, it would look good...

here's a try using the new glass material and the Skindigo mat preview scene.
render time about 30minutes. The glass was almost immediate, what took awhile was the little light balls inside to lose some noise. this is with Indigo .8 stable.

Whaat- how do you get a texture to wrap evenly around the sphere? Am I missing something in my sketchup skills, or is it a matter of going in and rotating the textures to get it to look right?

Man you guys work fast!!

Here is another test. The first image is using the Thin Glass material with a bump map. Only the top surface of the water has been modeled. The white spots are specular reflections of the sun. The second image is of a Specular material with the same bump map settings (IOR=1.33, no absorption). The water is modeled as a volume. The bump map is applied to all six sides of the 'water box' so that may have contributed to the results. Render time for both images was 30 minutes.

Whaat