Texturing Question

[pwrdesign]

Hi!

I've got a glass wall that will have a frosted city silhouette on the lower part, the glass walls is assigned with a glass material, and what I did was to place a shape just a few mm outside the glass wall, that I textured with frosted glass and used an alpha of the silhouette as  opacity map. This seems to work but the "cut out" parts of the shape seems to block the reflections of the glass wall, see attached render.

I found the "THIN" tickbox under Refraction and that helped, but it made the frosting effect a lot more boring :)

Any idéas?



best Regards Patrik

[maru]

uhh... tried mapping reflection/refraction glossiness with the city silhouette bitmap?

[pwrdesign]

For the frosty silhouette material?

[pwrdesign]

I think I managed to solve it!

Started the final render... and... :)
Best crash message I've ever seen lol

[pwrdesign]

No I didnt solve it.. This bothers me, must be an easy solution...

It must be possible to place an object with an clipmap in front of glass without ruin the reflection on the glass behind?

[maru]

Ok, I do not get it what you are trying to achieve and what goes wrong. Can you post a real world example? Or a schematic drawing of what it should look like?

[pwrdesign]

Ok, on the test render in this attached image, the red area is the shapes that are textured with the "frosted glass silhouette"
The shapes are lines extruded up to shapes, so they dont have a thickness, see the lower illustration that shows how its made... the blue think lines are the glass and the red think lines is the shapes that sit a few mm outside the glass.
The glass has a simple glass material assigned. And the shapes has a frosted glass material assigned with the opacity map also shown in the attached image.

If I render without the shapes in front of the glass it looks great, but when I render with the shapes in front of the glass, the top "opaque" parts (black areas) of the shapes seems to block the reflection in the glass behind.

[maru]

Ok, and why not like this? (one object, one material)
edit: there is a small error, the map should not be instanced, these should be 2 separate b&w maps

[pwrdesign]

Have to wake this topic up again. For the last delivery I rendered one image without the frosted texture and one with it and then composed it in Photoshop.
Now I'll do some changed to the frosted texture, and I want to understand whats causing this.

What I have is glass textured with a clear glass texture, 1 mm outside of that glass wall, I have a rectangle converted to editable poly, attached with a frosted material with an opacity map.
Whats happening is that the whole rectangle looses the reflectivity, should the opacity map just "cut out" the parts that shouldn't be frosted? And then display the glass material behind it? Why does the cut out parts block the reflection in the glass behind it?

[romullus]

maru has shown you a proper way to do this, why you still want to do this wrong way?

Anyway, try to check on thin / no refraction on your frosted glass material - i think it should fix it.

[pwrdesign]

Maru's way of doing it is the correct way, but the way the scene is modeled / exported from a cad environments, makes it hard to do it like that.
I would of course like to add the frosted material settings inside of the glass material, but its not possible now, I need another surface/shape just outside like this.
And other renders that I'm used to like Maxwell, Vray wouldn't block the reflection with an alpha/clipmap like this, but I'm 100% into Corona now and want to learn why it does it.

Best Regards Patrik

[maru]

Does the problem disappear if you switch glass mode to thin for the clear glass panels?

[pwrdesign]

I tried thin on the frosted material and that made the effect of the frosted parts to weak.
I tried it on the clear glass panels behind, and it kills most of the reflections, but the problems still appear what I see.

[maru]

Can you send a simplified version of the scene or just some simple objects + textures showing this problem? I think this is the "reflections seen through solid glass" problem ( https://coronarenderer.freshdesk.com/support/solutions/articles/5000516180 ) but maybe it is worth checking...

[romullus]

I tried thin on the frosted material and that made the effect of the frosted parts to weak.

Then uncheck thin glass mode and give thickness to your frosted glass plane. Apply shell modifier with very tiny amount like 0,01 - 0,001 to it.