Experimental support of parallax mapping in 2.13

[Arcturus]

One thing I wanted to test was .md5 meshes. Parallax mapping doesn't mesh very well with them, but if you crank it up to 11 you get something that looks like polished metal. Of course you can forget about proper texturing, but it reacts to light believably.

 

[MirceaKitsune]

It definitely bends weird in this case. But conceptually it's pretty good and doing its job best it can: Still impressive to see something like that in TDM!

[Arcturus]

UV seams are very visible. Other than that I think it's usable.

Here's the material:

textures/test/parallax_gold
{
	diffusemap	textures/test_parallax/parallax_gold	
	{
	blend specularmap
	map _white
	rgb 1
	}
	{
		blend parallaxmap
		map textures/test_parallax/parallax_gold_height
		min -1
		max 1
		//refineSteps 5
		//linearSteps 20
		//grazingAngle 0.3
		offsetExternalShadows 0
	}
}

I used two noise textures made in GIMP: https://drive.google.com/file/d/1O77ZcNIkYetGk_w_53JXgwpntwOyEkKJ/view?usp=sharing

Generally .md5 mesh will look like any other geometry as long as it's not deformed by animation:

[peter_spy]

It would be nice to see a performance comparison on that. A scene with typical materials vs. parallax versions. R_showprimitives, CPU and GPU utilisation increase, stuff like that

[Arcturus]

On 10/28/2024 at 4:06 PM, Arcturus said:

Generally .md5 mesh will look like any other geometry as long as it's not deformed by animation

I lied. Actually parallax mapping works fine with animated .md5 models.

There must be something else going on with the builder model, and now I wonder if it has something to do with this situation:

With lower specularmap values looks like it's a bit rougher.

Continued in this thread.

[Arcturus]

 

[nbohr1more]

This will be great for an acid trip \ hallucination based mission!

[MirceaKitsune]

At last: We have Mandrasola consumption implemented in TheDarkMod

[stgatilov]

On 10/28/2024 at 1:44 AM, Arcturus said:

One thing I wanted to test was .md5 meshes. Parallax mapping doesn't mesh very well with them, but if you crank it up to 11 you get something that looks like polished metal. Of course you can forget about proper texturing, but it reacts to light believably.

Could you please explain where is heightmap used on the builder model?
How does it look without heightmap/parallax?

[Arcturus]

@stgatilov Builder guard has a uv seam in the middle of the chest and the texture is mirrored, so that thew me off. I don't think it works well in cases like this, but as my later video shows parallax mapping generally works with animated md5 meshes. And just to be clear, I'm not saying we should put it on our characters, I was just experimenting. That video of the builder shows parallax mapping with extreme values, because I found it interesting.

[Wellingtoncrab]

All of the parallax materials shown off in the anniversary demo video (and more) are available in the dev build dev17234-10914. Just search for the suffix "_parallax"

 

[MirceaKitsune]

It still feels unbelievable that I'm seeing these in TheDarkMod, the detail is absolutely staggering

[datiswous]

How would you make the edges look good? Currently it looks weird where it stops on the edge.

I mean with the cobblestones.

Edited December 12, 2024 by datiswous

[HMart]

3 hours ago, datiswous said:

How would you make the edges look good? Currently it looks weird where it stops on the edge.

I mean with the cobblestones.

This is not real geometry tessellation this is cool but is a fake trick, a optical illusion, the surface is still flat, so it cannot do anything about the edges.

Parallax Occlusion Mapping (POM) is just a improved (and way more heavy) parallax mapping affect. 

Spoiler

Bellow another perhaps better video explanation for this stuff.

https://www.youtube.com/watch?v=cM7RjEtZGHw

 

Edited December 12, 2024 by HMart

[MirceaKitsune]

Just realized something: The new parallax effect would be a great way to get model-less building modules, for creators who'd rather try those over the model panels! They provide enough depth to realistically simulate bricks and beams and even windows, enough to look as good as sets like "models/darkmod/architecture/modules/exteriors/ext_timber01" and the others: You'd only need to create some extra geometry for corner pillars to hide the geometry edge effect in parallax, otherwise it should offer the needed depth to have detailed 3D building walls directly on brushes

[datiswous]

34 minutes ago, HMart said:

This is not real geometry tessellation this is cool but is a fake trick, a optical illusion, the surface is still flat, so it cannot do anything about the edges.

Yeah ok, but it still needs a solution, no? Otherwise it cannot be used.

I was thinking maybe you have to add a border to the texture.

Edited December 12, 2024 by datiswous

[Wellingtoncrab]

3 hours ago, datiswous said:

How would you make the edges look good? Currently it looks weird where it stops on the edge.

I mean with the cobblestones.

There are a number of ways a the parallax effect might look "weird" on edges as it is just an illusion. There is the perspective distortion on edges, the fact the effect just doesn't work at glancing angles, the displacement not tiling perfectly across edges, being able to see "past" the edge into the parallax itself, etc.

This is why in the brief window this was a popular technique in games, you would often see it on something like a portion of brick wall that was surrounded in beams. Or in more modern example in Deus Ex: MD it used on cobblestones where you always have curbs to flank it.

Just like any "trick" you need to use it in a way that plays to it's strengths and hides it weaknesses.

1 minute ago, datiswous said:

Yeah ok, but it still needs a solution, no? Otherwise it cannot be used.

I was thinking maybe you have to add a border to the texture.

Did you consider adding a border with geometry, such as a curb?

[HMart]

1 hour ago, datiswous said:

Yeah ok, but it still needs a solution, no? Otherwise it cannot be used.

I was thinking maybe you have to add a border to the texture.

It has solutions, the easy ones are those the others talked about.

[Arcturus]

You can do something like this:

I would argue parallax effect doesn't look that terrible on round corners anyway:

 

[MirceaKitsune]

Yes: A round patch should mitigate the effect of parallax being constrained to real geometry. Just make sure the material coordinates are perfectly aligned. For buildings my advice would be to have a pillar brush jutting out in corners.

Which reminds me of my question earlier, still curious to hear answers: Can we have material based building modules with parallax, as an alternative to the building module meshes? The new building modules are great but I'm definitely running into my fair share of issues with them: Having depth-based beams and panels for both building exteriors and interiors could look really amazing!

[peter_spy]

Probably not.

In case you didn't notice, game industry played with POM for a short while, and then mostly ditched it, because it's too performance-heavy. POM uses either path or raytracing, and it needs quite a few steps to make the shapes look good and not like a jelly or something. It requires quite a bit of optimisation to reduce tracing steps to be mostly nearby the player and nowhere else.

Besides, as GPUs went more and more powerful, and hi-poly to low-poly model workflows were already in use, it was much much cheaper to just add more geo to existing models and use LOD.

[stgatilov]

On 12/13/2024 at 9:54 AM, peter_spy said:

Besides, as GPUs went more and more powerful, and hi-poly to low-poly model workflows were already in use, it was much much cheaper to just add more geo to existing models and use LOD.

I'm not sure this is true.
Even with per-pixel raytracing, POM seems to be faster than throwing more polygons.

Perhaps you want to test it yourself?
It would really interesting to see competition between parallax maps and high-poly + normals maps (perhaps tessellation shaders also?)

But it is indeed easier to just throw more polygons at the problem, no need to dance around the quality issues.
Today's "cutting edge" approach is to use shitload of polygons with auto-generated LODs and hope that GPU does not die rendering it (UE5 Nanite).

[peter_spy]

4 hours ago, stgatilov said:

I'm not sure this is true.
Even with per-pixel raytracing, POM seems to be faster than throwing more polygons.

Perhaps you want to test it yourself?

Is it with modern RTX cards or with older hardware? I have no idea whether my RTX 3060 is a good candidate, but I assume these RT cores don't work automatically with POM. But yeah, I have a game-ready example with these cobblestones:

Normalmaps only:

Full geometry:

I also have more optimised variants of these.

Is parallax shader in the latest dev version, or can I download it separately?

[stgatilov]

2 hours ago, peter_spy said:

Is it with modern RTX cards or with older hardware? I have no idea whether my RTX 3060 is a good candidate, but I assume these RT cores don't work automatically with POM.

Raytracing is special API, it has to be used explicitly. And it does not even exist in OpenGL.

Quote

Is parallax shader in the latest dev version, or can I download it separately?

It is in the latest dev version, but it is not something that magically works for all existing shaders.
You need to find a material with parallax stage, or create a custom one.
The latest dev build contains many parallax materials made by @Wellingtoncrab.

[Wellingtoncrab]

6 hours ago, stgatilov said:

But it is indeed easier to just throw more polygons at the problem, no need to dance around the quality issues.

More polys/geometry usually isn’t easier in the context of this game, where making content which runs at all is about producing clean sealing geometry and portalization.

For all its faults an illusion like POM, which derives detail while retaining minimally complex sealing geometry seems well suited to that and the workflow of most mappers.

Maybe hardware tessellation could achieve something similar with less of the drawbacks, but I am pretty happy with this so far.