How do I Create a Sand Dune ??

[cyphyr]

Hi All
Title says it all, how do I create a Sand Dune topography. I have Googled extensively and I cant find any tutorials or software to make this effect. Smooth rolling hills, yes, but not the distinctive profile of a Sand Dune. I imagine that this is probable at the moment more in the provence of World Machine but I would have thought it would be within the procedural capabilities of TG2. I would also be interested in how to make the sand ripples that charactise these features. Looking forward to your response.
Richard

[Volker Harun]

As usual I am rendering.
But I would try the following:
Create a displacement on a flat terrain which is large scaled (Feature Scale 1000, Lead in 900, smallest 600)
Try to invert the displacement, play with contrast and roughness settings, maybe change the perlin and warp

[Volker Harun]

Attached a simple Dunes-TGD.

Volker

[groverwa]

Gday

I have tried twice to reply to this topic but they have dissapeared into the great unkown
Hrere is a zip file of World Machine files for sand dunes

Mike

[groverwa]

Gday

Here is a zip file of 3 renders using a modified World Machine file

Mike

[Sethren]

Originally when i created these sand dunes, i beleave that i had covered all of the types that exist in nature. At least i hope i did. It was very hard to imitate the real thing within World Machine so i hope what is there serves at least something decent for now.

[groverwa]

Gday Sethren

Many thanks for the files - they are a very good base to work from and gives an insight into how you produced them - sorry I did not reference them to you

Mike

[Sethren]

Nah, no worries. I forgot i even provided them until they were mentioned. I have been doing so much sense then.       

[cyphyr]

Thanks for the files everyone, I'll post some renders soon, once I figure everything out.
Richard

[The Geostation]

Just being messing around trying to get river systems, and lo-and-behold I inadvertently stumbled across an excellent way of doing sand dunes.   See the attached simple tgd

I first thought that the scale was a little bit on the tiny-side (which shouldn't pose that much of a problem as everything else can be scaled accordingly), however on a more thorough check, everything seems ok.

Hope you like it.

Andrew Randle
The Geostation

[nvseal]

If you want to add ripples in the sand then you need to read over Dave's function explanations here http://forums.planetside.co.uk/index.php?board=6.0
This is an image I created a while back using a power fractal and functions. One thing to look out for when using the functions though is that the farther away they are the more unrealistic they look. As you can see in this image, I had to angle the camera in such a way that the distant ripples are not clearly visible.

[The Geostation]

Thanks for the pointer to the ripples.   Let's see what we can do when we merge the two

Andrew Randle
The Geostation