View Full Version : Stones and pebbles for Riverbed

Thomas M.
02-09-2009, 11:13 AM
I found the interesting Preset "Pebbles" on Preset Central from Rebel Hill and wondered how I could go even further (quality wise). I need to generate a riverbed for an underwater image which needs to be as close to a photo as possible. With 64bit I wouldn't mind to go for many single stone objects, but am afraid of how to place them that it looks real and the stuff doesn't intersect.

The displacement way from Rebel Hill might be great for the bottom stone, but I need a variety on top with smaller and larger stones/pebbles.

How could I generate this underwater rock garden with thousands of rocks without placing them all by hand, but still have them lying on top of each other. Is there a way to place them automatically, so that they are evenly lying side by side?


P.S.: Wouldn't mind to buy plug ins or extra software. Is Vue a solution? Need to render this stuff via a renderfarm and don't want to buy extra render nodes for Vue. Also I'm afraid there's no time to learn this program within the project. I already got Vue 5, though.

02-09-2009, 12:52 PM
I'd probably do just what you are saying. Start with the Rebel Hill texture, then build it up with instancing. To finely control the placement of the instanced rocks, maybe try veggipaint?

I'm having a lot of success using this technique with a similar project where I have to make fields of boulders in random piles.

02-09-2009, 12:53 PM
oh, Ive also noticed that at least with my craggy rocks, intersecting rocks don't really show up. My shot is in motion, though, so there isn't enough scrutiny.

Thomas M.
02-09-2009, 02:12 PM
My needs to be high res (8000px width, 4000px heigth). Point which troubles me is that I want stones which touch each other, as they are so close together, without interseting. I wonder if there is some intelligent software (plug in) in modeler which places "stones" in a certain manner onto an object underground so that they are lying next to each other and not inside of themselves.

02-09-2009, 02:19 PM
have you got any ref of a riverbed like the one you are talking about that you could share?

Thomas M.
02-09-2009, 02:27 PM




02-09-2009, 02:36 PM
How about creating an array of simple, subdivided boxes as spheres, then using a procedural displacement with a large scale, enough to distort the rocks away from being spheres. That way, you won't have geometry intersecting.

It will require massive amounts of geometry, but would be childishly simple to set up.

Thomas M.
02-09-2009, 03:56 PM
What about HD instance. Does it have some intelligent algorithm to spread the small rocks?

02-09-2009, 04:27 PM
Not as far as I know, though you can ask it to make a certain amount of instances per metre and it will make a perfect grid. You can then jitter this grid of instances, but you'll get overlap then, though I've used it for gravel in flower beds and it's looked fine. The camera's not as close as you're likely to get though, though I'd be tempted to use something like HD Instance for the majority of the river bed, and perhaps hand place anything for close shots.

I've not had time to try this plugin in by Svenart on these forums, you can see the thread here, it may do what you're after?


02-09-2009, 08:59 PM
You could use a few particle generators, gravity and hypervoxels to generate this. No polygons or objects needed. I mean it needs some tweaking, but I think the concept might work.

Scene is attached

Thomas M.
02-09-2009, 09:35 PM
Cool guys! I'll check the HV a.s.a.p. and contacted Svenart. Maybe that a way. I wonder if exporting from Vue is an option and if Vue can generate something like this nicely.