Having problems with Displacement Map

there are “seams” of nothingness… apparently where the triangle lines of the geometry are located… what is happening?

Re: Having problems with Displacement Map

Hmm, is your object smoothed? If not I would do so, than it shouldn’t have the seams if I’m correct.

Cheers,
Roevens Johannes

Re: Having problems with Displacement Map

I smoothed it to 70%! :frowning:

Re: Having problems with Displacement Map

Auwch that’s really weird, I can not help you right now then, I’m testing the Mac OSX version and due to some reasons (which I can’t tell) I won’t be able to take a look at the model then…
I’m sorry for this, well maybe upload the file already, maybe someone’s gaining some interest to inspect the model then.

Cheers,
Roevens Johannes

EDIT:
I just found this in the ‘known bugs’ for Vray 1.5, I’m quite sure this might help you out!
“+ Curved, smooth Objects are sometimes rendered facetted. Explode and remake group or component to fix this.”

Hope that helped.

Cheers,
Roevens Johannes

Re: Having problems with Displacement Map

I sometimes get this effect on large areas of displaced grass. What I do to disguise the seams is to have another copy of the geometry directly underneath that doesnt have displacement (just a normal diffuse map). So when the geometry above displaces and opens up those seams you see the other map underneath that then ‘hides’ the seams effect. Hope you get what I mean.

Re: Having problems with Displacement Map

To my experience, displacement maps work on a grouped flat surface (i.e. a rectangle). I may be wrong, but I think you will have problems if your geometry is made of many shapes at different angles at the intersection of the seams. You may want to group each of them into simple flat areas and follow edonk’s instructions for hiding the seams. Also, please attach an image of your original geometry without the displacement maps. Good luck!

Re: Having problems with Displacement Map

Re: Having problems with Displacement Map

I would also like a sollution to this problem… I have the same problem.

Re: Having problems with Displacement Map

That’s what I thought.

Aceshigh, your geometry is a curved/organic shape and not a flat one, that’s why displacement maps have holes at the seams/intersection of each of your geometry. Well, that’s my thought but I may be wrong.

The only way is to hide the holes as previously mentioned.

Honestly, I only use displacement maps on a flat surface.

Could anyone more knowledgeable about displacement maps help here?

Thanks!

Re: Having problems with Displacement Map

but Teofas has done it

in this thread
http://forum.asgvis.com/index.php?topic=5225.0

I will follow his steps there… it seems there are some other parameters I should change, in the Options Window…

Re: Having problems with Displacement Map

humm…my bad, i guess it’s working depending on your parameters…seems like you might try different options and render till you get the result desired. I have not tried with grass/fur, but with stone and it did not work well unless my geomety is flat. Good luck! :slight_smile:

Re: Having problems with Displacement Map

Yes but Teofas smoothed his mesh, that’s the problem here, just enter the group, select the whole mesh, right click on it → Soften/Smoothen
and just push up the smoothbar quite a lot, then you’ll get a nice result, hope this helps. :wink:

Cheers,
Roevens Johannes

Re: Having problems with Displacement Map

Another problem with that is the scene runs out of memory if it is just one large smoothed piece of geometry, hence sometimes the surface needs to be broken down into smaller areas. Thats the problem Remon_V will be having.

Re: Having problems with Displacement Map

I’m pretty sure your displacement problems are caused by UV mapping. For displacement to work properly your texture has to map across the whole mesh so that the displaced geometry from the edge of one face tiles through to the displaced geometry of adjacent faces. If each of your faces has a unique UV setup, then the edge of every face is treated as a the edge of a mesh, so your displaced geometry won’t “join” up.

Unfortunately, as we all know, SU’s organic UV mapping tools are worthless (read: non-existant), so the only way to successfully UV map that duvet mesh would be in another prog like 3DS Max, Rhino, etc and the import it into SU.

Re: Having problems with Displacement Map

aces high can you share the model you are using, i want to test it.

Re: Having problems with Displacement Map

I did a quick test to recreate your problem and it’s almost certainly caused by bad UV mapping. The images below show identical geometry with identical textures and displacement settings, but the first has the grass texture mapped (by projection) across the whole mesh, while the second has the grass texture applied simply to faces as SU does by default. Unfortunately while the projected texture method in SU is fine for relatively flat meshes like landscapes, it is almost useless for complex undulating meshes like bed sheets, curtain etc as AFAIK the displacement won’t work properly where faces are perpendicular to the projected texture. You’ll need to do your UV mapping in another prog and import the mesh into SU.

Re: Having problems with Displacement Map

thnx for the test Jackson… I could try and map it in Blender, but I’m not very good at it.