shadow but no shadow

Started by Dune, February 03, 2017, 02:47:18 am

Previous topic - Next topic

Tangled-Universe

Could you upload a simplified version of your setup? Just the water, 2 atmospheres and camera?
I think you're right about my mistake, but I'd like to try and see if I can help out somehow.

The dark bands are possibly a meniscus effect or where light is actually being refracted away from the camera, thus causing black bands.

Dune

I'll do that tomorrow, am just about to quit for dinner. Thanks, Martin.

Last for today (am I sounding familiar?), still no good.


N-drju

February 03, 2017, 12:38:34 pm #17 Last Edit: February 03, 2017, 12:46:58 pm by N-drju
Quote from: Tangled-Universe on February 03, 2017, 11:56:44 am
Could you upload a simplified version of your setup? Just the water, 2 atmospheres and camera?


That would be useful no doubt. I think that the last picture for today doesn't quite make the cut indeed. :( All rays are gone. Shadows not very visible either.

_______________________________________

I just realized that you obviously cannot pull off that trick with thick object population... objects do not have the "visible to other rays" option either. Damn!
"When dictatorship is a fact, revolution becomes a right."

zaxxon

Caustics in TG would be wonderful! Or at least some kind of good 'fake'. I think you've covered some of the aspects of the problem, and maybe there is no solution. Nice experiments regardless.

I put the trout model and the maps up in the File Sharing area here for anyone who wants them.

Dune

That's a cool gesture of you, Doug.

I've just thought of something else, but that wouldn't throw the light on all ground stuff and there's another problem. It's possible to convert the wave displacement to a mask, after stretching it in Y and rotating by the sun's angle, that could work as a mask for additional illuminated cloud, hence 'rays'. But the origin wouldn't stay the same after rotating, so there's a problem.

I don't know how it would work on an exact copy of the water layer (some masking function added of course) with an invisible setting, but visible to other rays. Would that still throw a shadow in the water? Being exactly where the water plane is you wouldn't have reflection or shadows on top. You'd only need to tell the cloud to receive shadows from surfaces. But the water plane has shadows turned off, for obvious reasons, so that may not work.
And increasing lighness of the shadows parts to the needed value for 'normal' light would make the 'beams' and caustics light up, relatively. I'll try something like that later and upload a file.

bobbystahr

Quote from: cyphyr on February 03, 2017, 08:08:47 am
Have you looked at the caustic generator program, there's a paid for version (€55) and a free one (with typical limitations)
You could use this to control the volume of a cloud layer. Micht do the trick with some fiddling ...

Paid version
https://www.dualheights.se/caustics/

free version
http://www.softpedia.com/get/Multimedia/Graphic/Graphic-Others/Caustics-Generator.shtml


whew, if y want the 64 bit  "pro" version it jumps to 180 EUR...think I'll stay amateur
something borrowed,
something Blue.
Ring out the Old.
Bring in the New
Bobby Stahr, Paracosmologist

bobbystahr

Quote from: zaxxon on February 04, 2017, 01:51:07 am
Caustics in TG would be wonderful! Or at least some kind of good 'fake'. I think you've covered some of the aspects of the problem, and maybe there is no solution. Nice experiments regardless.

I put the trout model and the maps up in the File Sharing area here for anyone who wants them.


Heading ther now, thanks Doug...
something borrowed,
something Blue.
Ring out the Old.
Bring in the New
Bobby Stahr, Paracosmologist

Dune

Here's a basic working file. The extra plane+shadow idea doesn't work, as far as I can tell.
The idea is of course to have the shadows/lights of the 'caustics' on all surfaces and cloudmurk except the water plane, also have the stuff above water partly visible through the water and the reflections of fish or whatever on the underside of the water plane, like in some of these references. Tough cooky.

Kadri


Had a look at your file Ulco.
Finding what you want looked harder.
I just saw that you could use the aurora kind of method to the cloud in the underwater and get rid of the shadow file over water.
One bad thing are the angles. But a metacloud approach could be used for that problem.



Dune

You can tilt the aurora, but I prefer a method with shadows instead of just lighting the cloud, so it will influence all light underwater, not just the cloud/murk. With a water shader or a single sided glass or even just a reflective shader it's easy to get something nice, but then you don't see anything above water.

Dune

RDM is at 1, glass shader in front area, reflective more distant. Just the shadow cloud for the 'caustics'.

zaxxon

They are both brilliant Ulco! The underwater scene works better in my opinion, but the the second definitely shows promise for the technique. The vegetation both under and above is also fantastic!

Dune

Thanks, Doug. I bent your trout a bit in ZBrush to get another posture, btw. You may have noticed.

zaxxon

February 05, 2017, 01:28:43 pm #28 Last Edit: February 05, 2017, 01:31:37 pm by zaxxon
Bend away! I originally had made several 'bent' variations as morph targets as well. I should probably tweak the mouth area of the map a bit as the trout were never meant for some of the close-up poses you've used. It's pretty exciting to see some form of caustics for underwater scenes in TG . Genius use of TG again!

KyL

very nice render Ulco. I would go a bit more murky but it's quiet nice already.

One cool thing to add could be the chromatic aberration in the caustics to fake the light diffraction. Maybe it's as simple as shifting the r,g and b channel in the map you use!

Cheers!