hi there,
i face the problem that i get distorted effects when i see through the rounded glass facade. would be nice if i could get some suggestions.
thx
Is it single-sided geometry? Refracted material needs volume.
If it´s single-sided then the whole thing is treated like a big glas-solid.
Firstly, reduce your refraction IOR to something close to 1.0.
Also, check your smoothing groups, the top edges of the glass should be on a seperate smoothing group to the inner and outer faces.
thx for your replies, refraction ior 1,0 solved my problem.
IOR 1 may have solved your problem but I dont think that would be correct for glass. As Sascha said, you need to make sure your glass has thickness…use shell modifier and then you can use the correct glass IOR. Think its about 1.53.
…surely if it looks alright it’ll do?
As an aside, I’ve used the proper glass IOR of 1.5-odd and the refraction looks totally wrong, far too much distortion (for want of better) between glazed and adjoining open areas. I’ve had to ramp it down to 1.05 to get what looks, at least visually, correct. Is there perhaps something I’ve not done which has made the refraction so wild?
Just a wild guess but did you model your glass curved? In real life the glass between the mullions would be a single flat piece and in your model its probably curving hence the distortion you’re getting. If it looks right with your mesh and 1.05 IOR thats fine and you can call it finished. If you want to keep working on it, then I’d make sure the extruded spline that you probably used to create the glass was perfectly flat between the mullions and you’ll be able to render it with 1.5 IOR.
No, this was perfectly flat glass. As you say though, if it looks right that’ll do; I just find it curious that using the correct physical values produces an effect which is not desirable.
Thickness
Again: be sure to use thickness! If you have single-faces and the raytracer hits only one surface it will look wrong! The ray enters a volume, is refracted once, but never get out, thus pointing into a completely wrong direction. It has to refract once more back into the air to get the right direction.
I´m curious: max montana and Stoo: Did you use single-faces? Please check it.
With the right mesh VRay will render proper results!
Oooh, I’m very Catholic with my glass: Extruded lines to create a mesh with volume and all that, thus everything should be right from the off. When I have the time perhaps I’ll review my workflow to check it’s not a flaw in my modelling or similar. As I say, by ramping the IOR to 1.05 or thereabouts produces a much more satisfactory result whilst my past and present colleagues also use similar values.
That was my point earlier…IOR 1.5 should work with glass that has the correct thickness as Vray is physically correct. Strange..
as i face the problem with curved objects for glass again i refound this post.
i solved the problem last time by reducing the refraction ior to 1,0. not physically correct but it was ok for me. no i remembered the hint to use thickness, and added a shell odifier to the glass, and it works just fine.
now the question: the last object was an spilne, i made the outline 1cm to get “thickness” and extruded the object. but it still gives strange results on the curved areas. so now, what is meant with “thickness”?
Can you post a screengrab of the strange results…
have you checked that all the spline’s vertices are welded and it’s correctly extruded?
I’d be curious to see if this was still a problem if you modeled the panels for that curved area as individual panes. I’m no glass expert, but would there really be such a huge single piece of curved glass? If there is such a thing it must cost a small fortune before installation.
@rivoli: what do you mean with “correctly extruded”?
depending on how you drew the shape, you might have one or more vertices not welded together. if that is the case you may end up with two sided planes instead of an actual object with thickness once the shape is extruded. I asked only because vray doesn’t have any problem with curved refractive objects per se, so it may still be a geometry issue.