Ground, ground, ground, ... and ground again

[anicg]

How do you go about ground, not large scale terrains. Imagine you are in front of a beautiful landscape, and you look down at your feet, the ground you are standing on, how would you do that in Houdini? do I have to go to Substance designer?

 

[davpe]

I would go to Megascans library.

[anicg]

How does it fit in the scene? If I understand correctly I would use a grid, and apply Megascans using the bridge (don't know how yet, but I guess that's how it's done). Now I have a grid, with lovely ground, but it's a grid, displaced, it's still a grid. HOw does that fit with the terrain, heightfield, the scene? How does the grid merge with the rest of the environment?

[davpe]

well you can do whatever you want to the grid. it can have any geometry detail. then you just apply megascans textures on top of it.

as for how to merge it with the rest of your environment, it's a very broad question that is beyond the scope of a forum post, I'm afraid. there is dozen of ways how to approach such a task and it largely depends on what are you working with and what are you trying to achieve exactly.

 

 

 

 

[anicg]

Apologies. my last question was a bit vague indeed. Let me refine it: That image I attached in the beginning, a guy looking at a landscape. So there is the grid and the heightfield. I'll attach it again. How do I merge them nicely.

Edited December 11, 2019 by anicg

[konstantin magnus]

Hi Mani,

a common way to increase surface details on terrains is to use displacement maps on regular quad meshes. 

Texture haven and HDRI haven are good places for getting free texture sets without registration:

• https://texturehaven.com/
• https://hdrihaven.com/

 

terrain_tex.hipnc

[anicg]

Great, thanks a lot, this has really helped. Just a question: from this angle we don't see much of the repetition, as the camera moves up, the repetition is blatantly obvious, how do you deal with repetition (even seamless) in the texture map?

[konstantin magnus]

There are various ways to avoid / reduce tiling:

• using procedural shaders
• blending various textures
• texture bombing

[anicg]

On 12/14/2019 at 8:22 PM, konstantin magnus said:

There are various ways to avoid / reduce tiling:

• using procedural shaders
• blending various textures
• texture bombing

If you can shade a bit of light on these techniques I'll be grateful.

- using procedural shaders: do you mean like create a shader without any image whatsoever? I was hoping to make use of the realism of images (Texturehaven, megascans...).

- blending various textures: I've tried blending various textures but the problem is the new blended texture becomes repetitive, it's the 0 to 1 UV space that get repeated. If I use uvtransform and scale it up, by default I'm repeating the 0 to 1 uv space, and my texture is assigned to that 0 to 1 uv space, so whatever I blend (unless I'm doing it wrong) will be repeated. Is there a way to make the blended texture appear on the second repetition and not on the first for example?

- texture bombing: what is this? is it legal?

 

[asmartkid]

41 minutes ago, anicg said:

If you can shade a bit of light on these techniques I'll be grateful.

- using procedural shaders: do you mean like create a shader without any image whatsoever? I was hoping to make use of the realism of images (Texturehaven, megascans...).

- blending various textures: I've tried blending various textures but the problem is the new blended texture becomes repetitive, it's the 0 to 1 UV space that get repeated. If I use uvtransform and scale it up, by default I'm repeating the 0 to 1 uv space, and my texture is assigned to that 0 to 1 uv space, so whatever I blend (unless I'm doing it wrong) will be repeated. Is there a way to make the blended texture appear on the second repetition and not on the first for example?

- texture bombing: what is this? is it legal?

 

- procedural shaders: yeah, that's what he meant. In my short experience in these topics, I have approached the issue with the second option:

- blending textures/materials: I currently having some successful results blending different materials along the terrain using diverse types of noises as masks, this way removes part of the repetition. The more different materials you add to the mix, the better the results. Also, scatter random objects along the terrain (even if they are little rocks) helps a lot on the realism of the results.

- regarding texture bombing, I have not tried yet but in the future will do without a doubt.

Hope it helps as a starting point!

 

EDIT: forgot to mention, using the different masks you can get from a Houdini terrain (using the slope, the erosion features, etc.) as the base for the different blends of materials is a good idea. But I'm sure more experienced Houdini users over here will discover more interesting techniques!

Edited December 16, 2019 by asmartkid

[anicg]

1 hour ago, asmartkid said:

- blending textures/materials: I currently having some successful results blending different materials along the terrain using diverse types of noises as masks, this way removes part of the repetition. The more different materials you add to the mix, the better the results. Also, scatter random objects along the terrain (even if they are little rocks) helps a lot on the realism of the results.

I'm missing something here: blending textures/materials happens in the uv space, right? seriously, is it right? because the screenshots below show clearly that whatever is mixed happens in that uv space. Now, if I increase the uv to 5 times, whatever is mixed is increased 5 times, so basically it is as if I have done absolutely nothing.

I have a simple material white, a second in red, mixed using a circle. Yes, I can use any mask I want, fine, but it will be inside that uv space.

I must be doing something wrong.

[anicg]

This is what I mean, 2 materials mixed using a circle as mask, the whole thing is being repeated, as if I have done nothing (or hopefully I'm doing something wrong)

I'm talking about a grid or heightfield converted to polygon which then gets a uvtexture node added, that will be used as the ground in the foreground.

I know how to texture terrains using erosion masks, but that's not what I'm talking about. It's just that grid/heightfield to which I apply texturehaven/megascans textures in the foregraound to sell realism.

Edited December 16, 2019 by anicg

[flcc]

Usualy in other renderer (i'm really not a mantra expert) you set texture tilling at texture level.
That's to say your terrain is in uvspace 0 1 and then you apply diferrent tilling scale to your different textures.
Or you can use multiples uv sets, and/or mix the two technique.
I'm sure it can be done in mantra but a real Mantra expert is needed here !

And by the way, there is a Texture Bombing asset (and some explanations) for mantra here.

[vinyvince]

In addition to methods lists by @Konstantin, similar to tex boming is  Stochastic Height Blending/Procedural-stochastic-texturing.

It is a really effective way to kill tiling on landscape, organic , natural asset, you could find implementation in Unity and Unreal

It mirrors, rotates, offset and blend textures seamlessly.

________________________________________________________________

Vincent Thomas   (VFX and Art since 1998)
Senior Env artist & Lighting & MattePainter & Creative Concepts
 http://fr.linkedin.com/in/vincentthomas

[davpe]

i think, if you want to do something custom (not using pre-made textures) the good way to accomplish this is to build as many shapes and details as possible on SOP level (faster tweaking and more straightforward). then use computed geometry maps to drive finer details in the material network. This general approach typically works great. If you need lower res geometry for rendering you can always bake everything into textures (but Houdini and Mantra typically deals fine with heavy geometry).

Some time back I did this thing as a practice. The tank is textured with Substance painter but the ground and other stuff are modelled and textured procedurally. 

I know this is relatively simple looking ground texture, and things get more complicated most of the times, but the approach would be very similar. Only more layers. If you can't push it far enough procedurally you can always pepper it a bit with scanned details.

[flcc]

 

On 19/06/2020 at 8:46 PM, vinyvince said:

In addition to methods lists by @Konstantin, similar to tex boming is  Stochastic Height Blending/Procedural-stochastic-texturing.

Indeed this technique is very interesting.
On the unity's shader author page here you can find a detailled descripton and the glsl code.
I tried to run it in "shadertoy" and it's a semi-success.
The definition of the elements used for the color space changes are done in the application.

it would be really cool to adapt this for houdni. Or to redshift as soon as osl is available.
So I took a quick look at the possibility to play with a glsl shader for houdini, but it looks like glsl it's only for viewport visualisation. Is that right ?

Edited June 22, 2020 by flcc

[vinyvince]

On 22/06/2020 at 1:00 AM, davpe said:

i think, if you want to do something custom (not using pre-made textures) the good way to accomplish this is to build as many shapes and details as possible on SOP level (faster tweaking and more straightforward). then use computed geometry maps to drive finer details in the material network. This general approach typically works great. If you need lower res geometry for rendering you can always bake everything into textures (but Houdini and Mantra typically deals fine with heavy geometry).

Some time back I did this thing as a practice. The tank is textured with Substance painter but the ground and other stuff are modelled and textured procedurally. 

I know this is relatively simple looking ground texture, and things get more complicated most of the times, but the approach would be very similar. Only more layers. If you can't push it far enough procedurally you can always pepper it a bit with scanned details.

It looking god David!

Yes, we agree here , only Houdini doesn't have something like Eeeve, and if you render in Arnold/redshift the viewport interaction and feedback is not be especially brillant,  you are blind excepted doing an IPR, aven even so if i want to see the result in one click at a specific mark on my shader, it's doesn t look like possible excepted if i plug everything manually (in maya you could , make your lookdev's work smoother..)

If you look how artist could work on an env in Unreal, like in this video from Andrew and Dice from 4 years ago, if if you love Houdini like i do, you might recognize there are some area here of improvement. Which the Labsù teams slowly but surely are trying to fill... Well at least that's impression...

There are other realtime technique which are interesting like Object Blending with Dither Fade, Pixel Depth Offset and Distance when you want to blend obj to ground or whatever.

Question... If i generated a surface between 2 other surfaces (similar to the now present "dirt skirt" from the Lab tool)  Do you know how this blending surface could "raycast" the shading from the different surfaces it wants to seamlessly blend?

 

 

 

Edited June 26, 2020 by vinyvince

[davpe]

On 6/26/2020 at 8:18 PM, vinyvince said:

It looking god David!

Yes, we agree here , only Houdini doesn't have something like Eeeve, and if you render in Arnold/redshift the viewport interaction and feedback is not be especially brillant,  you are blind excepted doing an IPR, aven even so if i want to see the result in one click at a specific mark on my shader, it's doesn t look like possible excepted if i plug everything manually (in maya you could , make your lookdev's work smoother..)

If you look how artist could work on an env in Unreal, like in this video from Andrew and Dice from 4 years ago, if if you love Houdini like i do, you might recognize there are some area here of improvement. Which the Labsù teams slowly but surely are trying to fill... Well at least that's impression...

There are other realtime technique which are interesting like Object Blending with Dither Fade, Pixel Depth Offset and Distance when you want to blend obj to ground or whatever.

Yes, Unreal and Eevee are realtime engines and it's main feature is speed. Both also come with some painful limitations steming from it's realtime nature, which prevents it to be used as a reliable film production tools (so far). 

But isn't this thread about how to make a detailed ground to match the plate, in Houdini? Discussing rendering capabilities of UE doesn't seem to be relevant to the original question. 

On 6/26/2020 at 8:18 PM, vinyvince said:

Question... If i generated a surface between 2 other surfaces (similar to the now present "dirt skirt" from the Lab tool)  Do you know how this blending surface could "raycast" the shading from the different surfaces it wants to seamlessly blend?

I don't know exactly what you mean, I guess that's a workflow specific to realtime rendereres. Seamless blending is typically achieved by making the cg extension look as close to the real thing, and then by compositing  

[vinyvince]

I have worked on a little less than 30 feature films over 20 years so yeah i know what you mean and i donùt know if i didn t express myself clean enough but my question and feedback had actually nothing to do with the render engine.

If you still think both the vfx technique used in film and games have nothing to learn from each other, i believe you should may be take some time to think again

[davpe]

2 minutes ago, vinyvince said:

I have worked on a little less than 30 feature films over 20 years so yeah i know what you mean and i donùt know if i didn t express myself clean enough but my question and feedback had actually nothing to do with the render engine.

If you still think both the vfx technique used in film and games have nothing to learn from each other, i believe you should may be take some time to think again

ok i don't wish to fight and i certainly don't think vfx and games don't have anything to learn  from each other. quite opposite actually. 

i just did not understand how your comment relates to the original question, which was how to do this stuff in houdini. i posted an example with a short description how i did it. 

your reaction was UE and Eevee is more interactive than Houdini. i guess everybody can agree on that but what is your point, i don't know