Epic's GPUlightmass

[virtualHC]

Is the new GPU Lightmass not working properly with runtime virtual textures? I'm using RVTs in my materials for blending assets to the ground, and in full raytraced movable lighting mode, both the lighting and blending looks great, but when using static lightning and baking it with the new GPU Lightmass, the lighting doesn't blend and seams appear at the intersection. See the screenshots below. The rock's geometry is intersecting and extending below the ground.

Raytraced:



GPU Lightmass:

[enoes]

Is the new GPU Lightmass not working properly with runtime virtual textures? I'm using RVTs in my materials for blending assets to the ground, and in full raytraced movable lighting mode, both the lighting and blending looks great, but when using static lightning and baking it with the new GPU Lightmass, the lighting doesn't blend and seams appear at the intersection. See the screenshots below. The rock's geometry is intersecting and extending below the ground.

Raytraced:



GPU Lightmass:

Change the lightmap res. Try again and share the results please.

[virtualHC]

Change the lightmap res. Try again and share the results please.

Lightmap resolution was already set a bit on the high side, at least according to the Lightmap Density visualization (which by the way, I have to switch my project to DX11 for that visualization to work, otherwise it crashes the engine). I increased it further so most of it is well in the red, and re-baked. This is what I got:

[enoes]

Lightmap resolution was already set a bit on the high side, at least according to the Lightmap Density visualization (which by the way, I have to switch my project to DX11 for that visualization to work, otherwise it crashes the engine). I increased it further so most of it is well in the red, and re-baked. This is what I got:

This is red previous is red maybe change and use the low res lightmap

[motorsep]

virtualHC Are you using denoiser? Try disabling it.

[virtualHC]

virtualHC Are you using denoiser? Try disabling it.

Same results, just noisier:

[Arkiras]

Does it work with CPU lightmass if you disable lightmap virtual textures?

I'd read in the RVT thread that RVT doesn't work with streaming virtual textures. That in mind... I don't know, maybe it is related to the fact that GPU lightmass requires streaming virtual textures for lightmaps to be enabled.

[virtualHC]

Does it work with CPU lightmass if you disable lightmap virtual textures?

I'd read in the RVT thread that RVT doesn't work with streaming virtual textures. That in mind... I don't know, maybe it is related to the fact that GPU lightmass requires streaming virtual textures for lightmaps to be enabled.

I haven't tried with CPU Lightmass, although I did attempt once but aborted it since it was taking too long (will try again at lower quality). RVT are working fine in the same project with dynamic and raytraced light. Texture streaming is off in my project but I will give it a try with virtual texture lightmaps disabled (which is optional for GPU Lightmass).

[Arkiras]

RVT are working fine in the same project with dynamic and raytraced light.

Not really relevant as raytraced/dynamic lights do not store their lighting information in lightmaps.

Texture streaming is off in my project

Texture streaming is not the same as streaming virtual textures.

[virtualHC]

Not really relevant as raytraced/dynamic lights do not store their lighting information in lightmaps.

Texture streaming is not the same as streaming virtual textures.

Ah! Quite confusing. I get it after reading the documentation ( https://docs.unrealengine.com/en-US/...ing/index.html ). I was bringing up the fact that they render correctly in realtime in case RVTs had anything to do with texture streaming. Not sure if it's any relevant but turning off Virtual Texture Lightmaps didn't fix the problem.

[motorsep]

Seeing no fixes/updates trickling down to 4.26 / master branch of UE4 after 4.26 release, I think it's safe to say GPU Lightmass is called "done" internally for 4.26 and we might not see anything new/fixed up until UE5. I hope I am wrong, but that's the feeling I get.

[virtualHC]

Seeing no fixes/updates trickling down to 4.26 / master branch of UE4 after 4.26 release, I think it's safe to say GPU Lightmass is called "done" internally for 4.26 and we might not see anything new/fixed up until UE5. I hope I am wrong, but that's the feeling I get.

Very likely there will be a 4.27 and possibly 4.28 version before 5 stable, so there's still a chance for updates.

[Miguel1900]

Hi all,

I have been working on a Lighting Lab scene, trying to test all (or a lot, at least), of lighting capabilities and major situations, to find best practices within a collaborative work. It has been setup for a good quality result, not super-high World Settings, nor not super-high dense lightmaps. I will be sharing it soon, after some more test, and you could make your own tests and/or to complete the scene (or create a new one) to make it more complete and more compromising for certain situations. This way, we will be able to spot weak lighting calculations, and it could be even useful (maybe, I hope), for the Epic's GPU lighting Team, trying to solve those certain issues.


DOWNLOAD the scene (would be great if you could search for errors, too): https://www.dropbox.com/s/dfzf8fhlet...g_lab.zip?dl=0


On attached images, at left, 'Old GPU Lighmass'. At right, new built-in 'Epic's GPU Lightmass:
- Some black seams over the distance (even if pixel streaming is disabled).
- Huge noise over the walls (even with and without denoiser enabled).
- Quite more slow. Over doubled the time, for this two comparison scenarios.
- Not BSP compatible.
- More noticiable seams between modular pieces joints.
- Sometimes, after building, it still says Lighting needs to be rebuilt.
- Sometimes, lighting can pass through 10cm walls and illuminate other walls behind.
- Problems with two sided materials.
- Not working with translucent lighting transmitance.
- Some big squared spots, of different sizes, even at 8192 (maybe because I had Denoiser disabled? But it 'should' be probably better, anyway)


IC, FB, without Denoise:


The same, with Denoise:


No IC, no FB, with Denoise:


Maxed out quality (on a 2080 Ti) 3mins, vs 27mins...:


Best regards!

[Miguel1900]

Duplicated, sorry.

[enoes]

Hi all,

I have been working on a Lighting Lab scene, trying to test all (or a lot, at least), of lighting capabilities and major situations, to find best practices within a collaborative work. It has been setup for a good quality result, not super-high World Settings, nor not super-high dense lightmaps. I will be sharing it soon, after some more test, and you could make your own tests and/or to complete the scene (or create a new one) to make it more complete and more compromising for certain situations. This way, we will be able to spot weak lighting calculations, and it could be even useful (maybe, I hope), for the Epic's GPU lighting Team, trying to solve those certain issues.



On attached images, at left, 'Old GPU Lighmass'. At right, new built-in 'Epic's GPU Lightmass:
- Some black seams over the distance (even if pixel streaming is disabled).
- Huge noise over the walls (even with and without denoiser enabled).
- Quite more slow. Over doubled the time, for this two comparison scenarios.
- Not BSP compatible.
- More noticiable seams between modular pieces joints.
- Sometimes, after building, it still says Lighting needs to be rebuilt.
- Sometimes, lighting can pass through 10cm walls and illuminate other walls behind.
- Problems with two sided materials.
- Not working with translucent lighting transmitance.
- Some big squared spots, of different sizes, even at 8192 (maybe because I had Denoiser disabled? But it 'should' be probably better, anyway)


IC, FB, without Denoise:


The same, with Denoise:


No IC, no FB, with Denoise:

Maxed out quality (on a 2080 Ti) 3mins, vs 27mins...:


Best regards!

picture is not work !