Just a few steps ... to procedural craters ...

Started by Volker Harun, August 23, 2009, 03:21:57 pm

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Henry Blewer

The displacement would use an image map shader. The terrain power fractal could be used. At the bottom is the blend by shader. Connect a multi-shader to this. (try it, a small node network may have to be made) Make sure that 'Fit Blend Shader to this' is checked. A seamless tile pattern of craters scaled correctly with maybe five tiles should work. The x and z mirror should also be checked. Power fractals can be added to break up the regular pattern which occurs.

Let me get back to this, I want to try something...
http://flickr.com/photos/njeneb/
Forget Tuesday; It's just Monday spelled with a T

Henry Blewer

This is a quick and dirty way to do this. I made a tgd (terrain file) so you could see what I did easily. You'll have to supply an image, something with high contrast would work best.
http://flickr.com/photos/njeneb/
Forget Tuesday; It's just Monday spelled with a T

Volker Harun

Hello,

indeed - I am very busy these days - doing some software development - acquiring B to C and B to B ... which is time consumpting but the base for some few free weeks with TG again ... maybe end of the year I guess.

Anyway, I try to give you some insight to craters to the end of the week.

Regards,
Volker

Volker Harun


acolyte


acolyte

Hey, what did the image map look like that you plugged into your sample file? Did you set it up to just render the craters from the current camera position or do I need to do some tweaking? When I render I keep getting sharp jaggies all over the terrain. I'm just using a small 256x256 gradated circle on a mid-gray background. Got any ideas?

acolyte

November 02, 2009, 10:39:50 pm #36 Last Edit: November 02, 2009, 10:41:34 pm by acolyte
Ok, i started messing with the file you gave me and after figuring out I couldn't project with a camera and still render using that camera I came up with this. (Check included image). It's really uniform, how can I get it to look really random and sporadic? Do I just make the image bigger? I also don't want the same shapes exactly just tiled all over the place because it will look like its repeated. Thanks for the file though, it definitely helped me understand a little more about what's going on.

Henry Blewer

Now you add power fractals. Some with large displacements along the normal, and one or two with lateral displacements. Input a compute normal to the power fractals with the lateral displacements.
Also a mask for just the crater rims will alllow more precise placements.
http://flickr.com/photos/njeneb/
Forget Tuesday; It's just Monday spelled with a T

Kadri

Njeneb , you know it better i think , there are maybe dem (?) files for The Moon and such...for Mars there are i know.
http://forums.planetside.co.uk/index.php?topic=6217.0  Acolyte you could alter such files with grey maps  power f. and so...

Kadri.

acolyte

@Njeneb
I think I understand what you're saying about the setup, but I don't think i'm getting it right. Do you think you could show me how you would set it up in your example file?

@Kadri
I appreciate the idea. I actually went through about a 2 week span at the beginning of the project where I was conversing with some of the guys at the Clementine project for mapping the moon trying to get height maps since they seem to be pretty hard to get a hold of. I would really like to try and go the procedural route until i'm forced not to because my project requires that I render a lot of different sections on the surface which need to look complex and different. In the end I think it would be a lot less work setting up a complex node structure than having to paint a ridiculously detailed height map for all the craters I need. Plus I don't think I would be able to render it because I would run out of memory.

Thanks for your help guys. Njeneb, I know i'm taxing your time, but any sort of visuals you can provide to help with this would help me get my head around how this stuff works. Hopefully Volker will be able to explain some more and if he ends up posting a preset on NWDA for sale, I will be more than happy to be his first customer. :)

Kadri

November 03, 2009, 01:39:41 am #40 Last Edit: November 03, 2009, 01:44:03 am by Kadri
Acolyte , excuse me if you said it here anywhere but what are you trying to do? From wide angle to near distant animation?
You seem to know what you want. In the end  i think you can make this with TG2.
But maybe if we/me know it more precise we could help you better on your project.

Edit : http://forums.planetside.co.uk/index.php?topic=7882.0

Kadri.

acolyte

@Kadri
Yeah, I have a pretty good idea of what I want. I started my own thread before I was directed to this one here http://forums.planetside.co.uk/index.php?topic=7902.0. If you look at my first post it has a link to a zip with my terragen file so far (before I started messing with these craters) and a sample render of what it looks like. I'm basically going for as photo-real as possible both from a few hundred kilometers up from the surface down to the inch on the lunar surface. Now, i'm by no means trying to create an exact replica in 3d of the actual surface of the moon, but it needs to look convincing enough to pass for the real thing to the average joe. Shouldn't be too hard, I have complete confidence in Terragen...but I'm still trying to wrap my head around these node setups. I'm only really used to material nodes in 3d, not procedural mathematical nodes, so its a bit convoluted right now. But the end goal, as you can see in that link, is to create a 3d moon in Terragen which will allow me to basically go as far out or as close in as I need to as I place my own imported 3d objects on the terrain for my project. That's why I think it's a better idea to stay almost 100% procedural because it will free me up from having to paint another displacement map any time I want to move to a new area, or make it look like i'm moving to a new area. Anyways, I hope all this is clear... :) I tend to ramble on and on. Thanks for your help again guys!

Oshyan

Actually it's probably best if you continue the discussion in the original thread as this one had more to do with Volker's procedural solution. ;)

Thanks,

Oshyan

DJ

I found a way to produce simple craters similar to these.
Maybe it's useful for someone...

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DJ

Volker Harun

Hey DJ!  ;D

Very fine use of the smooth step scalar here ... in fact this is the base of my voronoi craters, too.  :D

Attached is a work in progress.