Preserved Topic: Playing with raytrace settings

Cluttered tile room (84k)

Playing with Max 4, I made a fairly simple scene to try out different raytrace settings. I thought some of you might find it amusing.

This isn't really intended to be a finished image of anything; I just scattered some simple shapes around.

The conversion to JPG dropped the quality some, and there appears to be some artifacting at the very edge of the glass cylinder. I probably need to up the poly count on it.

Hey, that's kinda nice. I need to try using something other than POV primitives. =)

that glass object is really cool!

btw I'm thoroughly amused!

OOOOOOOOOOHHHH...um...what else is there to say.

it reminds me of a saying I heard once 'Does it mean you've been doing to much 3D modelling when you walk into a Cathedral and think "God...the poly count on this place must be huge!"? '




Pretty...What do we blow up first? - Unknown

I put some stuff on your image, hope you don't mind some suggestions. http://people.mw.mediaone.net/jgreu/images/lighting1.jpg

Also see if you can turn on caustics for that glass tube, it's throwing a flat shadow and it should be bending and focusing light behind it.

Also if you want accurate refraction, take the polys of the glass, copy them, flip them, give the inverted polys a nurface of air (black, no diffuce, no spec, 97-99% transparent, then paste the original forward facing polys back over the air ones, and merge points.

This will let the light bend through the glass like it normally does, right now it's getting bent once and continuing through, it should bend twice.

-Electro

Thanks for the tips, Electro. There are already three lights in the scene; one shadowcaster and two omnis for fill. They're not placed all that well, though. I'm still trying to get a handle on lighting. I'll try deleting the omnis and putting in the ones you suggested.

The objects are just playing around, really. The objective was to make a cool room, but it was a failure. I was aiming for a techno cleanroom sort of feel, to do a robot assembly scene. Somehow it turned into bathroom tiles on the floor and cubicle tiles on the wall

I do like the floor tiles. I'll probably save them for something.

I didn't have caustics for the cylinder shadow becuase I'm limited to Max's default renderer atm. It don't do dat. I might try faking it. The shadow is a hack.

Max's default renderer also does wierd things with raytraced refractions. Doing the inverted air polys wouldn't work, I don't think. Raytrace materials in Max seem to ignore anything inside the refracting object's shell, sort of jumping from one outside edge to the opposite one. I don't think the rays would see the air polys. I'll see if I can get it to work, though. There are lots of settings I haven't played with (that's why the thread is titled "playing with raytrace settings")

If anyone is interested, I'll rerender when I get my good renderer back online (Mental Ray). It features global illumination (like radiosity, but better, imo), and caustics. It has smart refraction, as well, so the cylinder would refract correctly as is.

Also don't be afraid to do some post on a render. 9 times out of 10 a straight 3D render will benefit from some photoshop

Usually it's adjusting levels/curves, and putting some bloom on the image (make a copy of the layer, gaussian blur about 10-20, set mode to screen, adjust opacity) http://people.mw.mediaone.net/jgreu/images/post.jpg

Hey, it's what the pros do

-Electro

Well, I looked into the refractions. The glass actually is bending the light properly, once entering the glass, and once exiting it. Both the documentation and a few tests bear that out.

You might have assumed that it was only bending once because I used a badly incorrect value for the IOR. Glass should be 1.44, and I used 1.2, so it's not bending the light nearly as much as it should. I probably should have used an even higher IOR, since the item looks like it would be a crystal knickknack (crystal should be IOR 2.0).

Max does have a pretty sophisticated raytrace material, apparently. I didn't really notice at first that it automatically handles internal reflections. That's why the wall is visible on the bottom inside of the cylinder.

I did do a little bit of post in PS. Just adjusted the levels. The image was too dark as rendered (again, because my lights were messed up).

mmmmmm...mental ray. Never have been able to afford that. Das...hows about an explanation of how to get light to refract properly, so that it passes right through and out the other side and will continue to shine, and pick up colours and blah, blah, blah. Always wanted to do that.





Computer Senility. I had a friend once who had it. His name was Gilbert, but he prefered it if people called him 'Ramases Niblick the third...Kerplunk, Kerplunk, Whoops! Wheres my thribble?'... - Kryton, Red Dwarf.