Does this work on other renderers? [SOLVED]


#1

Mirrors in C4D can’t deflect volumentric lights. Is there some other renderer that can simulate a laser beam deflected properly ?



#2

This would be a caustic effect (light reflected or refracted); many renderers support this (Including C4D) but they are often inexact and lengthy to calculate…


#3

Hmmm… never thought of it as a caustics effect …
In my mind seemed a lot simpler, like calculating one more volumentric light starting from that mirror…


#4

I’ve applied volume caustics but got nothing. Seems that volume caustics work only for transparent mediums…
Can someone confirm other wise ?
Even with these settings I got no secondary beam.


#5

You need to enable caustics as a render effect as well. Surface caustics work (i.e. a reflected light spot appears on the floor in front of the mirror), but the volume caustics don’t work (probably because C4D’s standard volumetric lights are not a true volumetric effect).


#6

Let’s get @Srek to have a say at this …


#7

I imagine Srek will say the same thing. I tried this in Arnold, but Arnold can only do soft, imprecise caustics, and it didn’t track the reflected beam through an environmental fog.

A true light simulation render engine, like Maxwell, would probably do it. Also Corona, which has excellent reflective and refractive caustics:

https://corona-renderer.com/features/rendering-quality


#8

Vray can do that too, here is an example I’ve made a few years ago: https://www.facebook.com/3drenderandbeyond/photos/2629419427082660
The physical result was very close to the reference photo.


#9

If you want to have a laser effect, why not use a spline, sweep nurbs and a pure Luminace material with glow effect on? Would be easier to pull it off, right? The deflection could also be easily faked with 3 nulls and a tracer for example.


#10

@xdennisx for static renders yes that can be easy. But making an animation with many bounces is impossible this way.


#11

Don’t think Octane could do this currently, but they are soon releasing PPM Hybrid kernel render option. PPM = Progressive Photon Mapping w/advanced caustics.

Currently Octane gives you caustics, but not w/this math. model.

This type of modeling is historically VERY heavy computationally.

This image is from academic paper on PPM:


#12

It works, just keep in mind it is entirely crap. Volumetric caustics only work within the confines of the volumetric light. Which means as soon as the ray of light hits the mirror it immediately leaves. The system was really 99% designed for making nice patterns through refractive surfaces, not shoot pewpew lazers at mirrors (fun fact, I once broke a digital camera by shooting a laser at the sensor. The photo came out great though but it fried the camera) You can work around this with a second larger weaker volumetric caustic light to define an area:

http://www.3dfluff.com/files/volcaust.zip


#13

This makes me laugh out loud. I can imagine 3 reactions to such a moment:

Visceral - I blew something up!
images

Financial - Damn…Mu$t replace!
thisSucks

Academic - This merits further inquiry
academic


#14

LuxRender seems to be quite good at this kind of stuff, not sure there’s a bridge for C4D though (haven’t tried LuxCore, perhaps that works)
https://forums.luxcorerender.org/viewtopic.php?f=2&t=2784


#15

Yes.

In fact LuxRender was the explicit inspiration for Octane’s upcoming PPM. An Octane user was persistent in asking for it repeatedly based on what he’d seen with LuxRender.

Finally Jules decided: “this is a good idea and we can do it.” Coming this next year.


#16

Ok, you’re right. What about XParticles? I guess you could also pull this off with Thinking particles but it’s been a while… https://f.io/8cg4nJ_G


#17

@3DFluff This is genius ! Thank you !


#18

@xdennisx There’s also this but I was looking for a more general solution. The laser beam was just an example.
https://nitro4d.com/product/magic-laser/


#19

Hahaha, i was just wondering if there isn’t a Nitro plugin for that :smiley:


#20

LuxRender looks so dope ! That wavelength dispersion effect …
Does Redshift support light dispersion ?