glass facade

[aluigi]

Hi all

i have asked this in the past but i stiil can't get the look i want.

I have a building with lots of glass and usually

i work with lightscape and the glass always looks

like glass.

I am doin this animation & stills in viz 4 and

i find really hard to get a shiny and reflective

surfarce. Ihave tried with glass, raytrace,hdri

applied to the reflectin map slot,glass from the viz library, override material etc. etc.

I have also tried max 5 with light tracer and radiosity. Reflection maps (thet seems to work on a simple sphere) thet not show very dood on the flat glass surface.

What should i do? I ask the expert.

I have attached an image of the model (in lp)

just to give a fill of what i am talking about.

I would highly appreciate your help on this one.

 

http://www.cgarchitect.com/forum/filepush.asp?file=pic-b1.jpg

[mbr]

I have not used half the things you mentioned, but from my experience you need something to reflect to look real. The gradient/sky background is not really anything beyond a subtle color.

Try putting a sky with lots of clouds and variation, and make sure it's reflecting. You could also make a simple shape outside of the camera view to test the reflections. That might put you in the right direction.

Also, if you are using lighttracer or gi, make sure you have at least one light set to SPECULAR only and include the objects you want (I am doing this now for metal objects on an interior - fake gi and gi usually don't included specular highlights, making things look flat if there are not raytraced reflections).

Hope that helps.

[aluigi]

Thanks markus

i am still trying and also following your advices.

an important thing to consider is that the model will be animated and for this reason the rendering time cannot get too high.

I saw some of your rendering - they are very nice.

i do you get the glass effect (even not reflecting) in your models?

cheers

[mbr]

Thanks. Most of the images just have a simple material, a dark green/gray, mostly transparent with a raytraced reflection (NOT a raytrace material).

I think this is especially important if it is animated because the reflections will change as you move about the building - it will bring it to life. Use a sky dome if you aren't already.

Just make sure you have the global bounce set to '1'(it defaults to 9 in Max) on the raytrace settings.

 

Some of my older images used a map in the relections slot, but that was way back and when I was using a 533 with 256 ram!

 

Try rendering a few frames once you get the look you like. It's beyond my knowledge (maybe something to do with the mapped shadows in memory), but the animations (interiors) I am doing now the first frame takes about 5 minutes, then each after that takes about 1. So keep the testing up and it will pay off.

[aluigi]

Thank again

i will try it.

i have attached a link so you can see the problem.

cheers

 

http://www.cgarchitect.com/forum/filepush.asp?file=test-01.jpg

[3d-doctor]

yep i'm with mbr

you need to have a enviroment to reflect

the link posted a couple of days back on some 360 degree pano background jpegs would be a good start

if you set glass to raytrac reflect 30-35 you'll be getting some pretty decent results out of the box

i would set my raytrace bounces to 2 just in case you have more than the building in the scene

maybe also a subtle noise bump map for glass distortion?

and don't bother with the ior as it causes more trouble than worth once you are large scale projects

if you put in a visible lamp source for the sun and ramp up the self illumination you could add a bloom in lens fx/post.............really depends on what you want from the project

[mbr]

3d - I am curious why you would put the bounce on 2? I've never used more than 1, but I had assumed that above that was for closeup details that you don't really do in this business, am I mistaken?

[3d-doctor]

i'm suggesting 2 bounces just in case there was for example another glass bulding opposite

depending on which render engine you're on you might not see it or the building would render black in the reflections (not nice) but true get the defaults down from 9 to 2 (or 1) will do wonders on rendertimes

[mbr]

3d - thanks, I'll have to read more into that.

 

So for interiors, do you use 1 or 2 bounces? I am currently using one and it seems fine, but I've never really played with it.

[renato]

Another one:

 

I don't know if this is useful for exteriors, but it works for interiors:

 

I always use a mask map in the reflection slot with a raytrace material as a map and a falloff map as mask, in the falloff settings use fresnel and increase the black color to a dark grey.

refraction must be around 1.1, 1.2, and opacity 5 or so.

Also, exclude the glass material for any radiosity calculation.

 

best regards