Author Topic: Caustics Shader + Shallow Water Shader  (Read 17129 times)

dandelO

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Caustics Shader + Shallow Water Shader
« on: August 18, 2008, 02:38:36 AM »
No matter, I'm an idiot.
« Last Edit: January 31, 2010, 01:08:32 PM by dandelO »

dandelO

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Re: Caustics Shader + Shallow Water Shader
« Reply #1 on: August 18, 2008, 03:22:30 AM »
No matter, I'm an idiot.
« Last Edit: January 31, 2010, 01:08:18 PM by dandelO »

Offline old_blaggard

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Re: Caustics Shader + Shallow Water Shader
« Reply #2 on: August 18, 2008, 04:05:12 AM »
Wow, very nice!  Thanks for sharing that.  I believe that Matt mentioned at one point that caustics were possible within TG2 for incredibly high values of GI quality and detail, but this will certainly go faster and it looks very nice, too.
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Offline Tangled-Universe

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Re: Caustics Shader + Shallow Water Shader
« Reply #3 on: August 18, 2008, 09:26:17 AM »
Wow, very nice!  Thanks for sharing that.  I believe that Matt mentioned at one point that caustics were possible within TG2 for incredibly high values of GI quality and detail, but this will certainly go faster and it looks very nice, too.

As a matter of fact I've been trying to test this yesterday.
I created a small waterplane with the camera just above it facing downward. Upped the sunlight's intensity to 8 and adjusted the size and roughness of the ripples so I could expect a certain suitable size of caustics.

Render the test at detail 1 and GI 8/8, GI 16/16, GI 24/24 and GI 32/32 ;D ghehe :P
But to no avail yet.
Maybe I have to make the subsurface reflective, so I'll try that.
Or I'm still not using high enough quality settings.

Martin

dandelO

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Re: Caustics Shader + Shallow Water Shader
« Reply #4 on: August 18, 2008, 12:47:45 PM »
Pffffft! I NEVER go higher than 3/3 GI. You're a braver man than I, TU! :D
I really don't think it's worth it, but then, I'm only making silly little pictures for myself as a hobby, not for commercial production. I do what's required to convince, in the fastest time possible. No physicists or directors are scrutinizing my angles of incidence, or indexes of refraction.

This faked version is really fast to render and the scales are editable through the 'constant vector 01' node values, now set to '1'.
Higher values in this node, e.g. x=2 y=2 z=2, will make caustic pattern scaled half as large as the defaults, lower values e.g. x=0.5 y=0.5 z=0.5, make the pattern output exactly double in size. In other words, opposites.

I'm really taken with the ability that TG2 has. I couldn't get quick, procedural results like I do with TG in any other program I own. As far as I'm concerned TG now makes Vue 6 seem like a toy. And people still moan about how TG takes 'too long to render' or is 'too buggy to use'. Pish! Give it a chance.

Offline Tangled-Universe

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Re: Caustics Shader + Shallow Water Shader
« Reply #5 on: August 18, 2008, 01:16:06 PM »
Pffffft! I NEVER go higher than 3/3 GI. You're a braver man than I, TU! :D
I really don't think it's worth it, but then, I'm only making silly little pictures for myself as a hobby, not for commercial production. I do what's required to convince, in the fastest time possible. No physicists or directors are scrutinizing my angles of incidence, or indexes of refraction.

This faked version is really fast to render and the scales are editable through the 'constant vector 01' node values, now set to '1'.
Higher values in this node, e.g. x=2 y=2 z=2, will make caustic pattern scaled half as large as the defaults, lower values e.g. x=0.5 y=0.5 z=0.5, make the pattern output exactly double in size. In other words, opposites.

I'm really taken with the ability that TG2 has. I couldn't get quick, procedural results like I do with TG in any other program I own. As far as I'm concerned TG now makes Vue 6 seem like a toy. And people still moan about how TG takes 'too long to render' or is 'too buggy to use'. Pish! Give it a chance.

Completely agree with that.
The case is that there's very little documentation, only this great forum with tremendous amounts of information which you'll have to find and sort out yourself.
For new users (new TG-users and to greater extend new 3D users) this will result in a long learningcurve.
Once you're getting comfortable with it things will speed-up and you'll also learn how to avoid unnecessary long rendertimes.

You're right about that I'm crazy ;D
I just wanted to see if the renderer indeed is capable of rendering caustics.
I certainly will use your technique when I really want to apply it into on of my scenes.

Martin

Offline arisdemos

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Re: Caustics Shader + Shallow Water Shader
« Reply #6 on: August 18, 2008, 03:15:31 PM »
Thanks for this clip, and I wil be attempting to use it in an upgrade of my first tg5 water transparency try.

Offline rcallicotte

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Re: Caustics Shader + Shallow Water Shader
« Reply #7 on: August 18, 2008, 03:39:29 PM »
This is cool.  Time to play some more...errr, when I get my work done.   ;D
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Offline rcallicotte

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Re: Caustics Shader + Shallow Water Shader
« Reply #8 on: August 18, 2008, 03:40:31 PM »
Oh yeah, here's the Water Library - http://forums.planetside.co.uk/index.php?topic=4459.0
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Offline arisdemos

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Re: Caustics Shader + Shallow Water Shader
« Reply #9 on: August 18, 2008, 04:35:34 PM »
dandelO have you tried to hook this caustic effect into your waters edge fake stone clip setup yet?

dandelO

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Re: Caustics Shader + Shallow Water Shader
« Reply #10 on: August 18, 2008, 11:03:07 PM »
Quote
Oh yeah, here's the Water Library - http://forums.planetside.co.uk/index.php?topic=4459.0

Cheers, Calico. How do we make it sticky?

Arisdemos: They work well together, I'll prepare a .tgd of both rocks and 'caustics'. Upload later. :)

dandelO

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Re: Caustics Shader + Shallow Water Shader
« Reply #11 on: August 19, 2008, 01:24:09 AM »
No matter, I'm an idiot.

Basic example .tgd attatched...

12413-0
« Last Edit: January 31, 2010, 01:08:57 PM by dandelO »

Offline Oshyan

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Re: Caustics Shader + Shallow Water Shader
« Reply #12 on: August 19, 2008, 03:03:53 AM »
Very cool results. The water topic has been set "Sticky".

In theory the GI may be able to create caustics, but I don't think it's really practical. Best to wait for a proper caustics solution which would not rely solely on the "fuzzy" GI.

- Oshyan

Offline Tangled-Universe

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Re: Caustics Shader + Shallow Water Shader
« Reply #13 on: August 19, 2008, 09:00:27 AM »
Although it looks like Spiderman's just been for a swim in this example.tgd,(I didn't spend much time on this ones' details. :D) it clearly shows how it works over a displaced surface.
By setting the max slope of the caustics to 90 degrees the pattern is stretched over and around the stones but, is cut off on the undersides of their curved surface. No light(or, little light) from above would shine there.
All I've changed from the settings of the original clip is: 'Constant vector 01' x=3, y=3, z=3, reduced the overall coverage of 'caustics' to 0.075 from 0.1 and made its luminosity tint 2 instead of 1.

When rocks are poking out of the water: Very close control is needed to cut of all caustics above the waterline, it's almost impossible because the water is not a completely flat plane. Any waves at all make small differences in height across the entire plane, it's tricky but it can be done convincingly(nowhere near perfectly) with some work. Easier to deal with a shoreline, just set height constraints with a little fuzz.

Basic example .tgd attatched...

(Attachment Link)

There are 2 Y-values for the heighth of the waterplane in the water-node. The lowest number is the one you should use for constricting the caustic-layer. Set it just beneath this value with a very low fuzzy zone and the caustics won't be placed upon stones which stick through the water.

dandelO

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Re: Caustics Shader + Shallow Water Shader
« Reply #14 on: August 19, 2008, 11:47:43 AM »
No matter, I'm an idiot.
« Last Edit: January 31, 2010, 01:09:12 PM by dandelO »