CoolColJ's test pics thread

Get feedback from others on your works in progress
User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Sun May 16, 2010 12:48 pm

Nice!

That's pretty smooth and blotch colour free for such a low SPP. Currently it takes well over 2000 samples to clear out out all the artifacts, and some bits never go away completely.
It always puzzled me why Indigo would splat some random colour in some area where there is no caustics.
It can get pretty bad with plain MLT, without bidrection

So what were the changes that you added?

Hope you guys roll out the new build ASAP :P
Guideline for max change: if you have large areas of smooth illumination, maybe use 0.01, for lots of bright small lights use maybe 0.005, and consider not using MLT at all (except if you have SSS or something).
Yeah, I've done a lot of experiments with these MLT values, but it's nice to get some concrete values from people who know the innards :)

Indirectly seen caustics without MLT? Not a chance, believe me I've tried BiPT, but it always tends to look far grainier on caustics and has no hope of rendering refracted caustics and other things.

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Sun May 16, 2010 12:54 pm

If I remember correctly you are on C4D J ?!
In Cindigo per default Sun renders in 2 layers, sun + sky! Disable this in Advanced Indigo Settings for a speedup!
Zomb-B

I tried this, and it makes no difference. Indigo is still crazy slow with sunlight refracted caustics :(

It renders a small patch and then nothing for a while, and then another small bit and so on. Even with a simple flat water plane/glass and no bump mapping etc

Do this in Luxrender, and it finds the caustics within 30secs, and starts to lay down caustics continously until the whole area is filled and starts to refine it, so that by 100-200spp you can see it properly

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Mon May 17, 2010 12:32 am

Well displacement does seem to work fine here, it just doesn't like my pool model for some reason...
As long as smoothing is turned off!

Pretty chuffed with the results - sweet! 8)

I did some of these in plain path tracing and couldn't believe how fast it was going! :o
CCJ_displacement.JPG
path tracing
CCJ_Cube in a water block.JPG
path tracing
CCJ_Cube in a water block2.JPG
Bidirectional path tracing
Last edited by CoolColJ on Mon May 17, 2010 12:36 am, edited 1 time in total.

User avatar
lycium
Developer
Posts: 1199
Joined: Wed Sep 12, 2007 7:46 am
Location: Leipzig, Germany
Contact:

Re: CoolColJ's test pics thread

Post by lycium » Mon May 17, 2010 12:34 am

You should see how fast plain path tracing will be in the next build... :twisted:

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Tue May 18, 2010 1:58 pm

lycium wrote:You should see how fast plain path tracing will be in the next build... :twisted:
Never thought I'd see over 100k samples per second on my PC, but I did! It used to be that 40-50k on a simple scene was fast for me...

anyway I found with the above scene, because the floor is so large, it really slows down the appearance of caustics!
I sometimes wish unbiased render engines weren't so random. Logically there would be no point in shooting much rays at the edge of the scene floor, since it's a distant horizon

User avatar
Borgleader
Posts: 2149
Joined: Mon Jun 16, 2008 10:48 am

Re: CoolColJ's test pics thread

Post by Borgleader » Tue May 18, 2010 2:19 pm

dude that render is sooooo cool how dyu un wrap the cube for the texture to be seamless like that?
benn hired a mercenary to kill my sig...

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Tue May 18, 2010 9:53 pm

Borgleader wrote:dude that render is sooooo cool how dyu un wrap the cube for the texture to be seamless like that?
I didn't do anything special, just a basic UV map with a seamless tiled texture

here is what the texture does, displacing a flat plane. With an offset, and a negative quadratic(b) of the same value as the displacement
im1274006606.JPG
Now the cube has rounded edges which probably gives the effect of wraping around - pretty cool it is too :)

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Wed May 19, 2010 11:09 am

Ok this is puzzling, after all the slow renders I've had with water caustics, I do a new test and the caustics showed quite a lot quicker, and there was bumpmap on the water surface! :?

The only thing I can conclude is that the pool model makes a big difference... maybe.
In the other pool scene I tried, that was slower, the pool was proper 3D enclosed model with beveled edges etc.

In this scene, the pool is just a simple plane, extruded down. There is no bottom, just normals facing up. Hard edges, and no textures.

Maybe having no bottom in the model speeds up Indigo's MLT since it doesn't have to shoot rays at the bottom of it. Or having no bevelled edges and textures does likewise....

I don't know why, but the caustics showed up a lot faster compared to before, and the surface is quite a high freuency bump map!

Didn't bother with basic Path tracing or MLT, since the rays have a hard time lighting up the underwater object

Bidirectional Path tracing at 500+ samples. Doesn't look like the caustics will show anytime soon, but some parts of the underwater objects did light up. Maybe after a few thousand samples, all the those little dots become caustics :)
im1274170123.JPG
Then Bidirectional MLT. At 2000+ samples, still needs more rendering time to smooth out, or I may need to use smaller Max Mutation Range settings. I used default Indigo settings here of 0.01 since I found a smaller settingS like 0.005 to 0.003 caused a lot of multi-coloured artifacts.
The underwater cube should have some caustics right?
im1274222810.JPG
I will have to investigate some more, I'm trying the same scene now but instead of using bump map on the water surface, I have the same texture doing displacement. So far it is rendering more or less the same speed, just looks better.
And then texture and bump map the pool surface, which has slowed things way down in the past.

reference etc :)
I see a bit of dispersion, although rendering it takes forever!
Image

Image

User avatar
ENSLAVER
Posts: 399
Joined: Tue Feb 20, 2007 1:49 am

Re: CoolColJ's test pics thread

Post by ENSLAVER » Wed May 19, 2010 4:03 pm

Those caustics look sweet CoolColJ, I want to jump in lol - What bump map did you use? Is it shareable?

User avatar
CTZn
Posts: 7240
Joined: Thu Nov 16, 2006 4:34 pm
Location: Paris, France

Re: CoolColJ's test pics thread

Post by CTZn » Thu May 20, 2010 1:05 am

CoolColJ wrote: The underwater cube should have some caustics right?
Wrong, you're shooting it's backlit face, it's in shadows. In fact I'm pretty sure you can guess a grazing light on it, might as well be subjective though :)
obsolete asset

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Thu May 20, 2010 11:13 am

ENSLAVER wrote:Those caustics look sweet CoolColJ, I want to jump in lol - What bump map did you use? Is it shareable?
I took the bump map off the Thea render demo :)


I kept the render going and even at 3100 samples, it still hasn't really smoothed out much, or the caustics taken on a sharper appearance like these pics - will try different settings, smaller Mutation Range of 0.25
Or maybe the bump map isn't sharp enough

Yeah the dispersion is pretty obvious, but I'll wait till I get a faster computer before I try rendering them :)
Image

Image

Image

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Sat May 22, 2010 11:54 am

after experimenting on many different types of texture bump maps will poor results, I finally had the bright idea of trying Indigo's built in Perlin noise shader for bump mapping! The noise itself even looks like a smooth water type shape :)

Scaling it up 400%, and using an output multiplier of 1% seems to be doing a good job on so far, will see when the render progresses how it turns out...
It certainly is more organic in theory, with better precision/resolution

Then to try it out with displacement, but should smoothing be turned on? And will Indigo crap up the mesh when doing so?

Soup
Posts: 444
Joined: Sat Jun 13, 2009 1:20 am

Re: CoolColJ's test pics thread

Post by Soup » Sat May 22, 2010 5:09 pm

Smoothing on for sure. Just make sure the mesh has a high poly count (or turn subD up) and you'll be okay. You'll only get problems with displacements if you can see the edges of the mesh, but as your pool is enclosed it'll be fine :)
ISL is probably the best bet though. Post results!

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Sat May 22, 2010 7:58 pm

some quick tests - using Indigo Shading Perlin noise to do the bump mapping on a simple low poly water mesh

Basicly what I did was blend 2 different Perlin noise. I had one at 400% scaling and 75% value, and the other at 900% and 25% value. And basicly added them together so total value = 100%
Then set the total output to 1%

It works fine if I keep the total multiplier output low/bump map amount at 1% or under.
But the underwater Cube does not seem to be lighting up.... and it definitely should have caustics on it...
im1274501616.JPG
At 700 samples
im1274497833.JPG
150 samples
if the total output is at 2%, you start to get these dark areas forming. You can see some caustics on the back wall and water in the sphere reflection :)
im1274499646.JPG
250 samples
Black artifacts are not an issue with a higher angle though. Caustics look to high in frequency. Will try reducing the noise octaves, but keeping the ratios the same.
im1274503130.JPG
200+ samples

I'll try displacement next, which should get around the black artifacts stuff

User avatar
CoolColJ
Posts: 1734
Joined: Mon Jun 25, 2007 1:47 pm

Re: CoolColJ's test pics thread

Post by CoolColJ » Mon May 24, 2010 12:51 pm

This is what it looks with the noise scaling at 400 and 675% for the 2 layers of Perlin noise respectively.
Displacing the water mesh, but with combined output of the noise set at 5%. The higher level creates more defined caustics, but seems to render slower

Looks ok above water
im1274532847.JPG
But a bit too simple underwater, maybe another layer of noise at a lower frequency will help. And maybe instead of adding the noise layers together, using mulitplication
im1274530369.JPG
real
ImageImage
Image

Post Reply
685 posts

Who is online

Users browsing this forum: Ahrefs [Bot] and 2 guests