Feature request: emissive materials/volumetric lights

[peter_spy]

The effect works as in other games, the room would look darker only because you'd be casting a shadow standing in a light shaft. Since the player shadow is off, this doesn't look that way, and it's not a problem.

[RPGista]

No, bikerdude is right, standing inside the light cone shouldnt make the entirety of the room appear brighter. You can see it clearly in one of the previous screenshots ( http://forums.thedarkmod.com/topic/19659-feature-request-emissive-materialsvolumetric-lights/page-3?do=findComment&comment=428009 ).

 

PS: This is becoming more and more impressive by the minute, duzenko. Great work.

Edited September 27, 2018 by RPGista

[peter_spy]

That's because so far just a shape defined by projection and spotlight cone, nothing else. It doesn't even use light color, and you're already jumping to real-life comparisons, dust particles and that kind of stuff. It's ridiculous.

[RPGista]

Nobody is "jumping" to anything, bikerdude just pointed out a visual glitch the same way you were pointing out others. Im sure duzenko is well aware of all the issues himself, but people are gonna try to help out and participate any way they can.

[peter_spy]

This not helping. How you seen how this effect works in other games? If you want this and decent performance, you won't get much more than that.

 

So far, the light volume needs to use the light color value and the falloff image (as either I'm doing something wrong, or the volume itself doesn't use it, only light does. Will check that later.) It already uses some depth-based alpha, similar to our fog particles, and maybe that will need tweaking to look beter, but that's it. And that's something to be taken care of later, when the basics is done. How hard is that to structure that in your brain, in order of necessity?

 

Otherwise, if you want a detailed volumetric lighting effect, go render yourself a static image in Vray or other offline renderer, because you wont get that and maintain 60 fps in all your scenes.

[peter_spy]

Yup, both light materials are projected until the end of the cone with the same intensity:

 

[Bikerdude]

personally Id be happy with the first effect as it like its cheaper on the pref hit. The only request id make is have the ability to dictate where the effect starts - as in so its not starting from a point, but where its further away and wider, which the mapper could then place at the surface of a window etc.

[peter_spy]

Duzenko, I added dev commentary so we don't get lost in what we have so far. I also added alphatest plane window to check whether lightshafts are working with shadow maps (but that's probably something for later).

 

https://we.tl/t-soCcfjBmz0

Edited September 28, 2018 by Judith

[peter_spy]

Duzenko, please ignore the version above, it turned out the projection was upside down This version is correct: https://we.tl/t-5qEFH0IInM

 

 

The only request id make is have the ability to dictate where the effect starts

 

You can already do that with "Use start/end" option in the light inspector window.

[duzenko]

You should control the start/end with the falloff texture (I know it does not work just yet)

[Bikerdude]

This will be a killer efx/SFX to have once you guys get it working.

[duzenko]

This will be a killer efx/SFX to have once you guys get it working.

Would you maybe revisit a couple of your released maps to make use of it?

 

The new test build:

• using the light color
• using the falloff texture
• added an optional volumetric intensity param

lights/glowtest/light_shaft
{
    volumetric 0.1
    {
        forceHighQuality
        map    lights/falloff_exp2
        colored
        zeroClamp
    }
}

• fixed what I suspect to break shadow maps on nVidia

 

https://drive.google.com/file/d/1dqR1zaOADwkWO9bRN0JlHZatL63mzbJK/view?usp=sharing

 

I'll be looking at the transparent shadow caster now.

[duzenko]

New build: shadow maps shader fixed to allow transparency

https://drive.google.com/file/d/1dqR1zaOADwkWO9bRN0JlHZatL63mzbJK/view?usp=sharing

 

[peter_spy]

I confirm the light color and intensity, it looks great. I still don't have transparency shadow maps, but that's something for another topic.

 

Volumetric intensity also works as intended, it's a good idea to have this kind of tweak. One other thing to improve would be to get rid of that banding in the light shaft itself:

 

But I guess this goes back to how poorly the engine handles gradient textures in general, and AFAIR, you're working on it too.

[Bikerdude]

Would you maybe revisit a couple of your released maps to make use of it?

I could do, The Gatehouse would be the first logical candidate and think of.

[duzenko]

One other thing to improve would be to get rid of that banding in the light shaft itself:

 

 

But I guess this goes back to how poorly the engine handles gradient textures in general, and AFAIR, you're working on it too.

For custom projection textures, can't do.

Only can work around the few standard textures I can break down to an algebra function with more or less precision (biground, exp, quadratic, etc)

[Bikerdude]

What the weird herringbone effect in the volume, it doesn't look natural imho..

[duzenko]

What the weird herringbone effect in the volume, it doesn't look natural imho..

Either

http://bugs.thedarkmod.com/view.php?id=4888

or the very correct projection shadow emulation - see the texture corner-to-corner rod. It would be casting that kind of shadow, depending on the view angle

[peter_spy]

That herringbone pattern kind of depends on how blurred the image is and what is its resolution. Higher res textures with sharp shapes will have this pattern more prominent.

 

I blurred the image so it looks like this now:

-->

 

And the result looks like this:

 

The banding is only visible only when you stick your nose into it.

Edited September 28, 2018 by Judith

[peter_spy]

I turned the projection texture light into a shadow caster (window frame is noshadows) and let AI in. It already looks pretty cool, even though the light shaft isn't occluded by geometry yet:

 

[duzenko]

What should be the next step?

[peter_spy]

IMO next thing is to make geometry occlude the light shaft. Maybe there should be a spawnarg similar to noshadows for this, so mappers can control it and disable it to improve performance.

[HMart]

What should be the next step?

 

Make a AI occlude the beam?

 

Make a way to give different densities to the beam, for example the beam is stronger next to the window and fainter has it goes farther away?

 

Make a material keyword to give it some animation or augment the shader so you have "moving particles" inside the beam to simulate moving dust?

 

I assume it can be binded to a moving light, i don't see why not, but if don't that could be also a next step.

 

Ability to have volumetrics of different shapes, we don't need to copy reality, this effect could be used to make some fantasy effects.

 

I can't think of anything else right now.

 

 

Btw imo this effect alone will help TDM reputation increase ten fold, when those saying TDM engine is old and lacks modern effects, see this, they will think UE4 my a** TDM engine is cool!!! ;P

Edited September 28, 2018 by HMart

[peter_spy]

Make a way to give different densities to the beam, for example the beam is stronger next to the window and fainter has it goes farther away?

 

You can already do that with falloff image and Use start/end option in light inspector.

 

Make a material keyword to give it some animation or augment the shader so you have "moving particles" inside the beam to simulate moving dust?

 

This can already be done separately via particle emitters.

 

I assume it can be binded to a moving light, i don't see why not, but if don't that could be also a next step.

 

It probably can already, but moving lights hurt performance like hell and should be avoided whenever possible.

 

Ability to have volumetrics of different shapes, we don't need to copy reality, this effect could be used to make some fantasy effects.

 

This should be possible when the light shaft will be colliding with geometry, so you can put it in omni light and make it shine through holes in an object.

 

All in all, this is performance heavy effect and should be used sparingly, for strong light sources like floodlights, or to simulate sunlight / moonlight, but definitely not for every light or every window.

[Bikerdude]

This is very cool.