Sand (Desert, dry lake surface, cracked surface)

Started by Alkin, June 02, 2009, 10:53:15 AM

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Alkin

Hi.
Ive searched forums for sand surface and come up with some results but mostly it is a dune texture like on this picture here which is also something i need but id like to know how to make ripples which are in bottom right corner of the picture.
Also i am interested how can i make something like this. Almost flat but with texture.
The last thing i would like to get advise on is how to make something like this

Thank you in advance.

P. S. Yes i know, i am complete newb. ))

RArcher

The first two are possible just using a powerfractal.  Simply spend some time playing around with the various values until you get something close, you will also get the benefit of learning quite a bit too.

The last one is also possible.  Perhaps see here for more detail: http://forums.planetside.co.uk/index.php?topic=6432.0


Seth

Quote from: RArcher on June 02, 2009, 11:50:30 AM
The first two are possible just using a powerfractal.  Simply spend some time playing around with the various values until you get something close, you will also get the benefit of learning quite a bit too.



errrr... did anyone already made good sand ripples using powerfractal ?
I know Wiwine did using functions but i don't remember good PF sand ripples from anyone (but i may be wrong of course)... and i spent some times trying but i was faaaaar from the picture i just checked (the first Alkin posted)

Alkin

Quote from: RArcher on June 02, 2009, 11:50:30 AM
The first two are possible just using a powerfractal.  Simply spend some time playing around with the various values until you get something close, you will also get the benefit of learning quite a bit too.

The last one is also possible.  Perhaps see here for more detail: http://forums.planetside.co.uk/index.php?topic=6432.0

I did spend ton of time with PF. And again i did manage to come up with some nice dunes but not ripples.

littlecannon

Hi Alkin... have you done a search for pelin noise (Function). I think you may have to use this to get what you want. I'm pretty sure there was a discussion on this a while ago. I would advise you what to do... But I don't have much of a clue when it comes to functions (shame).

BUT... I have found this http://forums.planetside.co.uk/index.php?topic=1168
and with a little magic... you could have the sand you always dreamed of.
Thanks, Simon.
I just need to tweak that texture a bit more...

Seth


RArcher

Ahh, I was mainly talking about the dunes themselves for the powerfractal.  For the close up ripples, I just use an image map based displacement to handle that:

http://forums.planetside.co.uk/index.php?topic=6560.0

Hetzen

Quote from: Seth on June 02, 2009, 01:31:48 PM
yes, functions.
not only powerfractal ;)

Are there any known issues using functions over powerfractals? It would seem that a Sine wave would be the right thing to use in this instance.

Seth

Quote from: RArcher on June 02, 2009, 01:49:57 PM
For the close up ripples, I just use an image map based displacement


yeah and the result is good, as the ripples i saw from errr... Saurav and Efflux (i think or was it Moodflow ?) ;D
but i would like to find a way to do some ripples with PowerFractals too

dandelO

#10
With perlin ridges set in the fractal's noise flavour and low, close values for scale, you can make decent looking sand ripples by stretching the X or Z noise, depending which way you want the wind/water to have piled the sand in relation to your FOV.

Here is a very quick shot at it just while I read this thread, quality isn't a factor here, just demonstration... ;)

[attachimg=#]

Here's the values I've changed in a default power fractal...

scales: Feature=0.5, Lead-in=0.5, smallest=0.25.
Colour: Contrast=1, roughness=0
Displacement: Amplitude=0.25, roughness=0
Noise: Flavour=Ridges, XYZ stretch= X=5, Y=1, Z=1
Warping: Disabled everything here.

The camera is 5m above the surface, these ripples are quite big then. :-\ You can get the idea, though.

I'm looking directly down the Z axis so the X value needs stretched to make the ripples go horizontaly like this.
To make tighter ripples, drop the Z-stretch value, in increments of 0.1 until you have the desired size, is how I'd go about it...

dandelO

Same thing, bigger scales and I've used a 3D painted shader to draw where the small ripples go, which are the same scales of the last post's with noise stretch - X=15, Y=1, Z=0.75. The painted shader is just plugged into the blendshader of the ripples.

Not perfect by any means but workable if you spent enough time on it.

[attachimg=#]

Hetzen

I spent a couple of hours playing with this, and here's where I got to using functions. I may spend a little more time with it. The trick with the ripples, is to to use Get Altitude to drive the Sine function, so the contours follow the landscape, and a Bias function allows you to give the ripples more of a steeper peak.

Seth


domdib

Looks great Hetzen - any chance of a node shot or clip file?