what's happening here?

[mhaze]

I'm trying to emulate Dunes excellent work on rivers and have hit a major snag.  I'm trying to colour the river bed a different colour and as you can see it ain't lining up. The preview shows the ground shader lining up perfectly but the render preview and indeed the render don't line up. I've included the tgd so if anyone is inclined they can play too. Any help grateful received.  Mick

[dandelO]

Hi, Mhaze. Swap the order of 'displacement shader 01' and 'compute terrain'.

You'll likely need to recompute the entire terrain with the river displacement if you want to control slope and altitude later for other shaders.

* Funny, I'm doing the same project too! Here's mine, generally the same setup...

[mhaze]

Cherrs dandelo - I suspected it had something to do with the compute terrain.  You are definitely further on than me I've got a horrible water colour very grey unlike Dunes water, my next challenge is sorting that, teh I need to create a convincing terrain.  Should keep me happy for a while.  Thanks again Mick

PS just discovered any compute terrain in the node network and something doesn't line up! If I simply swop the order of the compute terrain and displacement shader the water does not line up!!!!!!

[dandelO]

Try this, didn't need to do much to line them up.

Switched a couple of connections and unplugged a couple too(the water shader and warp shader don't need any input nodes). Put a negative offset in 'water surface layer' to line the water up to the terrain, I used half the depth of the river's cut for that. Also added a colour adjust to the warped shape to feed the opacity channel with a solid edged river that will extend just beyond the banks.

You probably don't want the water to be displaced by the actual cut either so it's now just displaced by the terrain before the cut and is a bit more flat(ish, the terrain is a bit rough).

Lastly, I put the red guide layer after the 'ground' shader too(and unchecked the blending shader in the 'ground node), that way you'll have the entire ground covered by rock and you can use the following red layer as a base to build the riverbed on top of.
Each time you reseed your terrain or warp shader the river should fit automatically to the new shape.

Hope I haven't confused things too much, I've a tendency to do that.

[mhaze]

Thanks dandelo look forwad to learning from what you've done.

[dandelO]

Not a lot, you had it all already there, I just juggled a couple of bits around.

[Dune]

Nice to see that you're doing rivers, guys. I'm curious to see what you come up with.

[mhaze]

Hardest thing I've attempted Dune! dandelo I've got rid of the displacement shader and used the  ground surface shader for displacement that way I no longer need the offset.  Generally cleaned up the water now got proper transparency just need to fine tune it.  Then I need to work on the terrain.

[mhaze]

Just had a brainwave.  Don't need a water shader just a reflective shade plugged into a suface shader - solves so many problems!

[dandelO]

... Except transparency, it doesn't always work in the reflective shader. You could set up a surface layer with transparent water around the camera that fades out over distance to blend into the reflective shader, if you're close up to the water and need it, that is.

[mhaze]

I've just realised it won't work anyway it only colurs the surface you need a plane lake object to create the flat water.

[Dune]

Unless you can make the planet transparent where the river needs it. Just hang some fake ground surface on a plane under it. Easier (theoretically, but probably possible).

EDIT: just tried it, but the planet can't be made transparent locally. Pity. The outside area remains black, whatever you throw over it. Maybe something to add in the future?