Window materials...

[tomsdesk]

...and the "cast shadows" checkbox: Playing with the light portal material (how cool is that!) and still didn't see the sun hitting the floor even with the "cast shadows" box unchecked on the "common" material in "Realistic glass"...only works using the "no shadows" material in "Architectural glass"? Also noticed the same alpha setting for each gives a different [transparency[/i]? Also, doesn't seem to be any difference in the amount of ambient light between the noshadow alpha10 and the noshadow alpha30 (though I only let this run for 5 passes so maybe that's it?) but a noticable difference with the common glass?

common glass, alpha 10, "cast shadows" unchecked

untitled2a10common.jpg (45.49 KiB) Viewed 7205 times

no-shadows glass, alpha 10, "cast shadows" unchecked

untitled2a10noshadow.jpg (52.05 KiB) Viewed 7204 times

no-shadows glass, alpha 30, "cast shadows" unchecked

untitled2a30noshadow.jpg (48.25 KiB) Viewed 7204 times

[Chris]

Hi Tom, you said you let it run for 5 passess... what preset?

The Interior progressive presets, which are built on MLT, don't use the "Cast Shadow" setting. Since they are all about 'realism', those presets ignore cast shadow, will treat 'fake' emitters as real emitters, etc.

The Exterior progressive presset will use the "Cast Shadow" setting, but isn't really appropriate for this scene.

So the differences you are seeing are probably from the difference in materials and the different alphas. 'Common' glass has refraction, and so is probably why you have less light in the scene. The 'no shadows' glass is actually a totally different material that does not have refraction.

[tomsdesk]

Chris, I used "easy 09", same as for the image in the other thread...good? So you are saying that even though the box isn't greyed out it works for some materials and not for others? Also, same thing for IOR since it comes up "1.520" on the "no shadow glass" material and you can adjust the setting?

[Chris]

Well yes and no. For shadows, it's not the material that's relevant. It's the render setting. So it's not grayed out because it's a perfectly valid setting for that material, just not when it's used with a specific render method.

And IOR is valid no matter what. But IOR governs more than just refraction; it influences reflection as well. So the IOR is useful and important in both the Common Glass and the No-Shadow Glass. It just doesn't result in refraction for the No-Shadow Glass.

[tomsdesk]

So what render setting should I use for this scene?...for the other one ( http://twilightrender.com/phpBB3/viewto ... =16&t=1030 )?

[Chris]

If your only lighting is through a window, I'd recommend Interior because it's a "complicated" light scenario. I suggest using one of the architectural glass materials for the window.

If you have a lot more lighting from other sources, Interior + will work great but you could possibly get away with one of the PM methods like High, High+ (for final quality).

[Fletch]

can you post the scene?

btw, this is a perfect situation for arch. glass common no shadow. it's basically why it's there as a template.