Author Topic: Fun with the crater shader  (Read 46430 times)

Offline 3DGuy

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Fun with the crater shader
« on: December 26, 2006, 11:49:58 PM »
I was playing with the crater shader and came to the conclusion that you can have negative values for craters :D. This means you can turn craters into spikes. Playing around with the crater shader I created the olympic logo.. sortof. There's just a basic power fractal applied to the planet, the rest is crater shader. For some reason the back spike is cut short. Don't know why that happened, should be as tall as the one on the left. The 3D view showed it allright.



Here's an another attempt at combining craters (both positive and negative values).

This one also has a strata and shear shader applied.

I know these aren't the best of renders, they're just intended to show the crater shader at work. It can produce some interesting effects, maybe it'll inspire someone to do some more interesting stuff with it :) Sorry if this is all known stuff, but I didn't see it mentioned yet I think.
« Last Edit: December 27, 2006, 11:17:43 PM by 3DGuy »

Offline Tim O'Donoghue

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Re: Fun with the crater shader
« Reply #1 on: December 26, 2006, 11:55:02 PM »
Using that technique, you should be able to mimic Wizard Island in Crater Lake:

http://www.planetside.co.uk/gallery/v/tg09gallery/CraterLake_aerial.jpg.html

Offline rcallicotte

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Re: Fun with the crater shader
« Reply #2 on: December 27, 2006, 10:48:50 PM »
Thanks 3DGuy.  Don't apologize for showing what you know.  It's a privilege to hear all of these things.  I'd be curious what your TGD file looked like on both of these.
So this is Disney World.  Can we live here?

Offline 3DGuy

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Re: Fun with the crater shader
« Reply #3 on: December 27, 2006, 11:17:18 PM »
I thought I attached them.. guess I didn't. That's what happens when I post in the middle of the night hehe. Anyway here they are.

Offline FrankThomas

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Re: Fun with the crater shader
« Reply #4 on: December 28, 2006, 08:08:48 AM »
Is there any way of setting the "circularity" of the rim (for want of a better word)

I've never seen a crater that's a perfect circle before but I haven't figured out how to deform it yet

Offline 3DGuy

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Re: Fun with the crater shader
« Reply #5 on: December 28, 2006, 12:38:13 PM »
I was wondering about that myself. Haven't found anything to set that yet. I'd like to see shaders applied to the ringshape (like you can with the rim, but then to the inward/outward) and make it an oval shape.. eggshape etc.
« Last Edit: December 28, 2006, 12:41:24 PM by 3DGuy »

Offline crazymonkey

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Re: Fun with the crater shader
« Reply #6 on: December 28, 2006, 11:13:30 PM »
very cool idea, so many things to play with...

Offline Oshyan

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Re: Fun with the crater shader
« Reply #7 on: December 30, 2006, 02:33:05 AM »
Nice work, good experimentation. One of the great things about TG2 as compared to TG 0.9 is that, although there are limited values on the sliders (by necessity, and in many cases to suggest "reasonable" values), you can also enter almost any numerical value you want into most controls. This allows for a great deal of flexibility and power to achieve unusual and interesting effects. Sometimes it just doesn't work at all, but often times you get really cool results.

I believe uou can distort the edges of craters using a Rim Shader input.

- Oshyan

Offline FrankThomas

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Re: Fun with the crater shader
« Reply #8 on: December 30, 2006, 03:10:12 AM »
Well, Oshyan got me thinking so I thought I'd give it a shot - does this look more like a crater ?
(yeesh - the things I do a 4 am ;D)

TGD file attached - have at it :)

[edit]
Forgot to mention that I used some pretty extreme numbers in the displacement part of the powerfractal
« Last Edit: December 30, 2006, 03:12:07 AM by FrankThomas »

Offline 3DGuy

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Re: Fun with the crater shader
« Reply #9 on: December 30, 2006, 03:14:31 AM »
It's still a circle. It's only distorted in height. Is there a way to dirtort the ring shape itself? Elongate it for instance?

Offline FrankThomas

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Re: Fun with the crater shader
« Reply #10 on: December 30, 2006, 03:18:25 AM »
yeah, that's what I was thinking - it's a lot more crumbly round the rim than before.  What I guess you'd want is some "Rim Thickness" Parameter that will accept displacement or power fractal shaders

Offline VermilionMartyr

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Re: Fun with the crater shader
« Reply #11 on: December 30, 2006, 04:16:37 AM »
Hmm...




Offline crazymonkey

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Re: Fun with the crater shader
« Reply #12 on: December 30, 2006, 07:17:47 AM »
Well, Oshyan got me thinking so I thought I'd give it a shot - does this look more like a crater ?
(yeesh - the things I do a 4 am ;D)

TGD file attached - have at it :)

[edit]
Forgot to mention that I used some pretty extreme numbers in the displacement part of the powerfractal

nice one mate ;D

Offline Oshyan

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Re: Fun with the crater shader
« Reply #13 on: December 30, 2006, 09:13:12 AM »
You might need to feed your displacement through a Redirect Shader to get lateral displacement on the crater rim...

- Oshyan

Offline FrankThomas

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Re: Fun with the crater shader
« Reply #14 on: December 30, 2006, 01:54:38 PM »
Now I'm a bit more awake ;D

I had a quick browse round the t'interweb for photos of craters and such.  Most of them are pretty much circular in shape - the rim is more or less eroded but the general shape is circular.  I'll have a go with Oshyans last suggestion if I can ever figure out how to do it