Canyon Wall Displacement (Collaborative Challenge)

[WAS]

I've been working for maybe... oh... several years. Trying to make natural looking canyon walls. I've got some approaches that turn out looking alright, but very "fake" or cartoony almost.



Maybe someone can explain how to setup a start, or look at my start and advise?

[Upon Infinity]

Have you tried working from the preset?  Most of the people who know canyons and other complex procedures on this forum are pretty dodgy when giving out details on techniques.

[Hetzen]

Most of the people who know canyons and other complex procedures on this forum are pretty dodgy when giving out details on techniques.

Not sure that's fair. What WASasquatch is looking for is something we've all been trying to achieve. I think the discussion and development would go further if we all understood the problem better. Lets have a real life image we can all look at and work out how to work out further.

I guess the provided scene gives the base shape in the first three nodes. I want to see what detail he's looking for TG to provide in reference pictures.

[AP]

Here are reference images that can help.

https://duckduckgo.com/?q=canyon+walls&iax=1&ia=images

I met some success with a distant canyon from a bird's eye view but close up is a whole other challenge. It looks like you have the general shape started well. Having the correct colors is the easy part. Maybe we can stretch some function nodes and i was looking for a function to use for that but with no success yet. I may already have some ideas in that area. That layered chiseled and deep cracked mix that is so hard to duplicate. And lastly of course eroding the entire structure correctly.

[WAS]

Here are reference images that can help.

This looks like a good one to start with

I think the discussion and development would go further if we all understood the problem better. Lets have a real life image we can all look at and work out how to work out further.

I think Hetzen is right, we seemed to go quite far, really fast with the eject topics, far more has been learned and discussed then in the past years.

Users that would like to join in and help solve these issues for the world of TG users sounds like a great idea to me.

From what I planned in the blue nodes, you can see I have some pretty "decent" channels that I mixed with a voronoi billows (for buldges). My theory was that it would pan out like cracks and ridges in lateral displacement. In practice though, it seems the translation to displacement isn't exactly as pictured and coming off a lot softer and rounded. It also isn't taking on the form I'd hoped for which means the angles I have based on X/Z are not going to work I don't think.

The reason I have new interest is viewing the beautiful pieces of René like this canyon wall which is just stunning (must be part of Terragen Galleries) https://www.facebook.com/photo.php?fbid=934437656638635&set=gm.915201408605883&type=3&theater

[AP]

That one photograph looks to be a good one to work off of.

René's canyon wall is very nice. His coloring represents the region fairly well. Erosion is needed otherwise the canyon lacks any type of geomorphology other then the main feature itself. Fluvial and weathering effects are needed on the smaller scales.

I found way to flatten certain smaller scale noises in varying alternative methods and stretch them out so i will post some ideas soon. The sheer rock is caused by weathering called exfoliation. Sheets of the exposed rock slip away and fall due to cracks or joints within the rock. This is what i mean...

[AP]

By the way Dune's square rock tests as good to browse over also.

[WAS]

Erosion is needed otherwise the canyon lacks any type of geomorphology other then the main feature itself. Fluvial and weathering effects are needed on the smaller scales.

That's actually a good point. I've made a bit more head-way and rebuilt my function. I'll post it up in a minute after I try to do a bit with Daniil's Erosion Shader. Not sure how will it will work AFTER the strata, but I'll try.

The big thing I have discovered is "Lateral Only" is based on the inner most displacement points of the slope. So you displacement you add with appear more smooth as it's blending with the outer displacement of the slope which extends PASSED the displacement you are adding.

To solve this you use "Lateral Normalized" which uses the displacement surface of the slope from what I gathered. This just all being my explanations of what's happening with these settings for the Displacement Function.

I found way to flatten certain smaller scale noises in varying alternative methods and stretch them out so i will post some ideas soon.

I look forward too it. Thanks for all the help Chris.

As a note: Due to Render Times, I think Erosion should be something we look at towards the end. I'm on almost 20 minutes of a test render with erosion masked. Actually looks "decent" for the erosion effect. Could be smaller scale though.

Finally finished at 40 minutes.

[Oshyan]

There are docs for the displacement methods here...
http://planetside.co.uk/wiki/index.php?title=Default_Shader_-_Displacement_Tab

- Oshyan

[AP]

Erosion should always be a last resort until you know you are satisfied with the overall terrain. Those adjustments can take enough time as it is. Not a problem helping out in this. This to is quite a challenge so why not be up for it.   

Thank you Oshyan for the link. It always helps to refresh the memory every now and then.

[WAS]

Here is what we have going on now. Looking a lot better.

There are docs for the displacement methods here...
http://planetside.co.uk/wiki/index.php?title=Default_Shader_-_Displacement_Tab

- Oshyan

Thanks for the link Oshyan. Not sure why, but there was definitely a lot more detail present on Lateral Normal.

So with this it seems there needs to be yet another, larger scaled displacement layer to create even more varied jetted areas and compressed areas with detail. Lateral like cliff hangs. Also needs possible another, even smaller scale crack setup.

Also there are some rough spots that need some polishing. I'm not sure where they are coming from though...

[AP]

Certain a lot closer in certain areas. Here in red is what i see and green still needs to be achieved, at least from what can be seen so far. A mix of more flat, some softer corners and wider strata.

I am currently rendering a very crude example of sharp scarped cliffs. There are several ways of doing what i have in mind so as crude as it may be, there are still man ideas left to explore.

[WAS]

Certain a lot closer in certain areas. Here in red is what i see and green still needs to be achieved, at least from what can be seen so far. A mix of more flat, some softer corners and wider strata.

I am currently rendering a very crude example of sharp scarped cliffs. There are several ways of doing what i have in mind so as crude as it may be, there are still man ideas left to explore.

Good eye, what I think can be done is a surface layer, using the base cracks as a input, and child layers as a new function setup for the new desired target look. Masked with a PF at high smallest scale settings and high colour contrast settings to give us are varied setup like seen in the image. Also maybe limited to a altitude as shown above where it seems to be common to lower altitudes. However that I'm not sure how to do besides a simple Displacement Shader to Scaler and Colour Adjust 0 - 1000 to create a height mask from displacement.

I tried something similar but I broke the original setup somehow and can't track down what I did wrong. Too late. I'll re-download this and try again in the morning. Maybe you can give it a shot.

May need to also use a Surface Layer as a Displacement Shader alternative to limit the displacement more to the walls and not the plateau buildup where it seems to go a bit crazy.

[Dune]

You're getting pretty close. I've had a quick play with your initial file and changed some stuff. Nowhere near, but it'll give you some additional lines of thought 

[mhaze]

My smooth voronoi cracks file - which is free from the NWDA store might help here.