can't get displacement on vertical wall...again.

[chrisS@422]

Nothing works for me.  I've searched and read all posts on the subject, just more confused as they're all different. Richard showed me a way, Franck showed me a different way, I think I've got the two confused and have created a mixed bastard monster using both techniques. either I'm setting it up wrong or forgetting something, I can never get displacement on near vertical geometry.
this is how I think it should work, PLEASE tell me if I'm wrong.

1. compute normal below main wall displacement
2. surface shader, set to vertical displace
3. PF (also set to vertical displace) into child of Surface Shader, with distribution shader connected to the blending shader
4?? compute terrain after steps 1-3?

please help before I start killing computers with axes!

[cyphyr]

Hang on I got an axe here somewhere
Displacement on near vertical surfaces is problematic.
You'll need Horizontal Displacement not vertical and try different settings in your compute terrain. In the sample attached I've upped it to 50 but this will depend on your scene.
Good luck
Richard

[Tangled-Universe]

I'm not sure if a painted shader will do any good if you only computed normals before it.

My guess, in general, would be to use a compute terrain with a very small patch size and perhaps use smoothing too.

After that you should be able to use a normal PF or redirect shader to displace the virtually vertical walls.

[chrisS@422]

Cheers guys!

Rich, thanks for the scene! I tried it but it only seems to work for Heightfield displacement for me? I'm running an image sequence through an image shader/projected cam, I dont know if thats the case but it seems to be true for this scene anyway

Tangled universe that worked perfectly!! the problem was using a compute normal instead of terrain, and changing the patch size. (ta rich as well ) I thought it was the other way round? so confusing this vertical displacment milarky, yet another completely different setup lol

thank you again guys!!

C

[Dune]

Martin is right. I used that method in this thread: http://forums.planetside.co.uk/index.php?topic=13113.30

It's a mask, but I think it should be possible with some blue functions to get some sort of stairs, or a series of simple shapes added up or something. Then you indeed raise it with a displacement shader. But the trick is to get the computed terrain to think it's a flat area, hence you set compute terrain to smooth terrain. You can mask this area out if you need unsmoothed terrain afterwards, for instance for displacement intersection+smoothing. You may also have to set the patch size to something very small, like 0.1-1. Then add the fake stones in a surface layer, masked out by a slightly larger mask, or by height.