[naxos]

Hi Maxwell guys,

here are 2 pictures with a.. her... "thing" in glass...
I want some absorbative-coloured glass...

I can reach that easyly within FinalRender (mapping colour and alpha of the absorption param), and i'd love to reach the same kind in maxwell (to have benefit of the aberration, nice lights, etc..)

notice the details i do love : thin parts of the object are almost-clear glass;
thick parts are fully coloured...

oh, also, i can reach that also with Renderdrive, and faster than the time needed to write this post, but ok, Rdrive is not GI yet

Finalrender picture :


My best Maxwell try :


So please great Maxwell users, help me to find out good abs. params to reach this nice effect

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[naxos]

also, there are some extra differences between the 2 :

in finalrender picture, i've put a rectangle light just above the "thing"...

so in maxwell i tried to put an emittive-material plane, then box above...
But, hey ! no light at all from that box... even the box itself was rendered black... i just put maxwell default emmitive mat onto it, noway !

[tom]

Hi Naxos,

The example you show doesn't seem real, just an exageratted example.
Below, you can find some experiments on absorbance.

Best regards,
Tom

http://www.maxwellrender.com/forum/view ... 40&start=0

©Thomas An.

[sidenimjay]

i have seen real glass that looks like your finalrender pic. perhaps not so dangerously pointy but true to life i'd say. i dont understand why some say its not real, and just seems like an over-exagerated example . . . . . perhaps it is just that maxwell cannot achieve the results that finalrender has.

the only potential option is to use a diffuse map on the glass, but this is only a hack and wouldnt
truly recreate the look of the colored glass from clear to blue.

have never used finalrender , but it seems to me the glass shader is a procedural shader that calls color based on depth and absorbance of the volume, and as we all know maxwell has no procedural shaders as of yet

i doubt that anyone can render an exact recreation of the finalrender scene with maxwell beta 1.2.2a .... and a single piece of geometry for the glass . . . .and no "hidden" lights sources to cheat with . . . .

[naxos]

Tom > maybe it is over-realist, dunno... FR is not a true-light based render, so i just mapped the absorbance as it pleased me...

both > but i agree with sidenimjay : i've already saw some pieces of glass almost clear when thin and very coloured when thick...
maybe no like this one, but not so far...

i'd just like to reach max possible that nice render...

[tom]

It's true that there are glasses looks like the example on the top.
This is multicolored glass and it's not homegenous in body.
And it's nothing about absorbance. There are 2 different substances blended.
It's OK absorbance is everywhere but what makes the glass color here less is not absorbance.


In other hand, a homogenous colored glass has absorbance this way.



I hope I could tell the difference between the absorbance and blend.
And as you said naxos, the glasses you saw are blended and they act
like in your mapped (is not absorbance) example.

Best regards,
Tom

[naxos]

ok Tom... i'm sooo happy you're right one more...
(oh, you have to know you're one of my heros on the web

ok, so if i want to render blended glass with maxwell : no way for now i guess, maxwell can't handle max's blend material, right ?


-----


and what about my emitter problem ? did i make wrong ? / forgot something to set ?

[tom]

Thanks for nice words I'm glad to be helpful.
Yes, it's not possible to render color mapped dielectrics yet.
Make sure your emitter surface's normals are not pointing upwards.

Best regards,
Tom

[WillMartin]

naxos,

In LightWave there is a gradient option for surfaces called "Surface Thickness," which does something for color and/or opacity of an object as sidenimjay said (if you're modeling gummi bears for example). My guess is that you used the equivalent in Finalrender for your "things." I personally love this option/look and hope it somehow finds its way into M~R in the future. I mean, though you rarely see it, technically you could have a real object that has its color changing so fluidly and drastically through it's volume, right?... though such rarities are surely not going to be a priority for a while for M~R I'm sure.

[naxos]

i can understand that Maxwell goal is to fit reality...

but think about those crazy 'Gallé' lamps :
they are 'not-polish' glass, coloured and from different density rough glass...

think about some kind of "injected" coulors into transparent / translicid plastics or glass...

FinalRender can help (and i guess other renderers too) with a "volumetric shader"....
But, even if i'm very very very happy with maxwell render, i'm a bit sad it only handles it's own shaders...

I hope next goal (after release 1.0 perhaps), will be to be able to render max's shaders... so we can use blend, mix and falloff...