What i am curious about, is how they made all those curved glowing screens in the demo (i guess that part was an emissive material), and how they were connected to Megalights. Because... emissive materials seem to have no relation to Megalights, and Arealights are not visible. Did they use the Emissive materials just for the visibility, and enhanced their light effects via an additional Arealight with the same texture for better lighting than what Lumen would give from this emissive material alone?
MegaLights (what a silly name 🙄) are closer to Raytraced Shadows (as they are). It's basically the same method, but alle lights get rendered / sampled in one pass (with other "magic") so the rendering ist much more efficient. If you're interested, look up some talks about RTXDI (I am very shure, it's the same thing / merge of the UE5-NvRTX Branch of this feature). Didn't know about the Postprocessing Controls, that's much more convenient :) Thanks
Having looked at the source for both RTXDI and UE 5.5, MegaLights are not the same. Direct lighting and similar solutions aren't incredibly new, there are many other examples of this. They're just popular, so you've heard of them. Go turn over some more rocks, read some whitepapers, etc.
Lumen is real-time global illumination. It replaces the baked GI workflow however it requires more powerful gpus. Games that need to support older machines will have to stick with baked GI which runs faster. Megalights replaces static and movable lights which become expensive to render the more you have them. Megalights solves this performance penalty limitation where it allows you to place as many lights as you need in a scene with shadows enabled. Haven't tested it but it should run well even on low end hardware
@@bushgreen260 No, static and moveable lights represent artificial lights like light bulb, street lamp or flash light i.e. point lights, spot lights and area lights. This also includes the sun light. Let me explain what Lumen does using this example: Say you have an environment setup with a sky box and sun light. When you create a closed room with an open window, the light coming in can't properly illuminate the interior of the room in a natural way. You'll have one spot that is well lit while the rest of the room is dark. That's because no light is bouncing inside the room. You could compensate by increasing the intensity of the sun t to make room appear brighter, but that would make outside unrealistically too bright. The correct solution was to bake global illumination which will calculate light rays entering the room and bouncing onto the floor, walls and ceiling and thus creating a more realistic lit room by the environment outside. Lumen is an alternative to baking in that it calculates the bounce light and shadows in real time. Hence with Lumen enabled, you get realistic looking room interiors and caves with real time global illumination without doing GI baking.
@@bushgreen260lumen only affects movable and stationary lights. static lights are pre baked and are the cheapest. if your scene doesnt have a moving sun, baking the directional light would be a good idea performance wise and it would look better than lumen. but do keep in mind, every time you move a single object or add any objects, you'll have to rebake the lighting to fix artifacts. thats why people like lumen alot, its waay less work than handling static lighting. but it comes at the cost of ALOT of performance. reducing the number of potential buyers for your game. Days gone is a game that uses baked lighting with a dynamic sky in a smart way without using lumen, as a result it looks amazing and runs amazing. this performance only matters in case of games. if you're making a product showcase or archviz it doesn't really matter
Megalights are ok, but hardware raytracing tanks my perrfomance by 35%, though my scene is already Lumen optimized, and I have some weird shadow artefacts with megalights
I'm not sure if you are getting less definition in shadows with Megalights. It looks like you are getting soft shadows (we saw them clearly on Epic Games demo) that may be even better but i can't tell just from this video. Some branches from the tree are very thin and i'm not sure that in real life you would have such a hard shadow cast on the rock with Megalights off.
It needs more looking into for sure, I agree can't base it off of that one light. I saw similar with larger statue in this scene but needs more research
@@MrKams1i have done some more researches. Megalights is blurrier but i guess it could be a very good compromise i would like too see how it react to transparency and reflections too.
how well does it perform without hardware raytracing? And does it replace the need for virtual shadow maps? Id love to see if an old school dx12 card like gtx 980 can use them.
Hi less GPU time is better, it equates to higher frame rate. The correlation is approximately 16.66ms to 60fps. For the number of lights used we can see better performance and lower ms for mega lights. Hopefully someone can use the profiler more accurately to test thousands of lights, over a longer time period 😂
@@MrKams1 Yea, that's exactly what (sort of) shocked me. Because I thought Megalights would be more costly in terms of GPU power. since, every (Mega) light sources can now cast shadows. How come it less demanding (mind-blown.gif) 🤯
@@LibertyKyo It is less demending because when you activate MegaLights, the renderer uses a completely different method to compute light compared the the one that has been used in other rendered in the past. That new light rendering method has been developed to allow better light computation performance so you can now add more light than before for the same GPU time cost or increase the number of lights. Now I don't know how this new light thing work under the hood but it is probably very clever, like Nanite and Lumen.
![[MV] A leap of faith...ความเชื่อใจครั้งสุดท้าย (From "Petrichor the series")](http://i.ytimg.com/vi/U1piZH2CNXA/mqdefault.jpg)
Megalights is pure gold, and in some cases the lighting is way better.
This might just be better than nanite in terms of performance gain and artistical freedom
yes , nanite is cool but i don't depend on it for my scenes , but im really limited by the Numbers of movable lights however
What i am curious about, is how they made all those curved glowing screens in the demo (i guess that part was an emissive material), and how they were connected to Megalights. Because... emissive materials seem to have no relation to Megalights, and Arealights are not visible. Did they use the Emissive materials just for the visibility, and enhanced their light effects via an additional Arealight with the same texture for better lighting than what Lumen would give from this emissive material alone?
Thanks for checking it out
Awesome. FPS in the editor can sometimes be way off from a compiled exe. Also hitting F11 and seeing FPS at fullscreen would be worth seeing too.
Thanks for this, promising stuff
MegaLights (what a silly name 🙄) are closer to Raytraced Shadows (as they are). It's basically the same method, but alle lights get rendered / sampled in one pass (with other "magic") so the rendering ist much more efficient. If you're interested, look up some talks about RTXDI (I am very shure, it's the same thing / merge of the UE5-NvRTX Branch of this feature).
Didn't know about the Postprocessing Controls, that's much more convenient :) Thanks
Having looked at the source for both RTXDI and UE 5.5, MegaLights are not the same. Direct lighting and similar solutions aren't incredibly new, there are many other examples of this. They're just popular, so you've heard of them. Go turn over some more rocks, read some whitepapers, etc.
@@Derjyn You seem to be right. Epic didn't merge this as is. The performance and look are very similar, from my testing.
Worked for me aswell without hardware raytracing
*What's the difference between lumen and megalights?*
*Do you need to use lumen if you use megalights or is using only megalights enough?*
Lumen is real-time global illumination. It replaces the baked GI workflow however it requires more powerful gpus. Games that need to support older machines will have to stick with baked GI which runs faster.
Megalights replaces static and movable lights which become expensive to render the more you have them. Megalights solves this performance penalty limitation where it allows you to place as many lights as you need in a scene with shadows enabled. Haven't tested it but it should run well even on low end hardware
@@myxsys so before megalights was lumen handling the static and moveable lights aswell?
@@bushgreen260 No, static and moveable lights represent artificial lights like light bulb, street lamp or flash light i.e. point lights, spot lights and area lights. This also includes the sun light.
Let me explain what Lumen does using this example:
Say you have an environment setup with a sky box and sun light. When you create a closed room with an open window, the light coming in can't properly illuminate the interior of the room in a natural way. You'll have one spot that is well lit while the rest of the room is dark. That's because no light is bouncing inside the room.
You could compensate by increasing the intensity of the sun t to make room appear brighter, but that would make outside unrealistically too bright.
The correct solution was to bake global illumination which will calculate light rays entering the room and bouncing onto the floor, walls and ceiling and thus creating a more realistic lit room by the environment outside.
Lumen is an alternative to baking in that it calculates the bounce light and shadows in real time. Hence with Lumen enabled, you get realistic looking room interiors and caves with real time global illumination without doing GI baking.
@@bushgreen260lumen only affects movable and stationary lights. static lights are pre baked and are the cheapest.
if your scene doesnt have a moving sun, baking the directional light would be a good idea performance wise and it would look better than lumen. but do keep in mind, every time you move a single object or add any objects, you'll have to rebake the lighting to fix artifacts. thats why people like lumen alot, its waay less work than handling static lighting. but it comes at the cost of ALOT of performance. reducing the number of potential buyers for your game. Days gone is a game that uses baked lighting with a dynamic sky in a smart way without using lumen, as a result it looks amazing and runs amazing.
this performance only matters in case of games. if you're making a product showcase or archviz it doesn't really matter
@@bushgreen260 Lumen handles indirect lighting, megalights handles direct lighting and shadows. They can be used together or separately.
Megalights are ok, but hardware raytracing tanks my perrfomance by 35%, though my scene is already Lumen optimized, and I have some weird shadow artefacts with megalights
I'd like to know what kind of amazing technology it's using here?
is megalights dependant on temporal AA? (TAA/TSR). is it noisy without using them
have you tried megalights with grooms?
I'm not sure if you are getting less definition in shadows with Megalights. It looks like you are getting soft shadows (we saw them clearly on Epic Games demo) that may be even better but i can't tell just from this video.
Some branches from the tree are very thin and i'm not sure that in real life you would have such a hard shadow cast on the rock with Megalights off.
It needs more looking into for sure, I agree can't base it off of that one light. I saw similar with larger statue in this scene but needs more research
@@MrKams1i have done some more researches. Megalights is blurrier but i guess it could be a very good compromise i would like too see how it react to transparency and reflections too.
@@Daburademo Could it be that hardware ray tracing is not enabled in the project settings?
You'll see more of a performance difference when you get into the hundreds or more of lights.
how well does it perform without hardware raytracing? And does it replace the need for virtual shadow maps? Id love to see if an old school dx12 card like gtx 980 can use them.
It requires hardware raytracing, it can and probably should replace all shadows (doesn't support directional lights yet, so need those with VSM).
@@ZacDonald ive seen a youtuber claim eh disabled hardware ray tracing and it still worked. Is this something you have tested?
I'm not really convinced about all this new stuff.. Why not finish what they have started?
@@dotcom4389 they just put more stuff and doesn't improve things like the water etc. Partition..
please post your system specs
@@hellohogo rtx 4080 i7'13700
7:18 why is that using Megalights uses less amount of GPU time? I don't get it
Hi less GPU time is better, it equates to higher frame rate. The correlation is approximately 16.66ms to 60fps. For the number of lights used we can see better performance and lower ms for mega lights. Hopefully someone can use the profiler more accurately to test thousands of lights, over a longer time period 😂
@@MrKams1 Yea, that's exactly what (sort of) shocked me. Because I thought Megalights would be more costly in terms of GPU power. since, every (Mega) light sources can now cast shadows. How come it less demanding (mind-blown.gif) 🤯
@@MrKams1 Annnnnd, 1.22ms vs. 3.81ms. That's just a third of the amount of GPU time costs compare to normal/"casual" lights. WTF!?
@@MrKams1 Yea, would also like to see what hundreds (if not thousands) of Megalight sources be like 😂
@@LibertyKyo It is less demending because when you activate MegaLights, the renderer uses a completely different method to compute light compared the the one that has been used in other rendered in the past. That new light rendering method has been developed to allow better light computation performance so you can now add more light than before for the same GPU time cost or increase the number of lights. Now I don't know how this new light thing work under the hood but it is probably very clever, like Nanite and Lumen.
Basically is just more close to Pathtracing in real time 🤷♂🤷♂🤔🤔🤔🤔
you can already have Path Tracing in real time. Games such as Cyberpunk 2077, Alan Wake 2 and Black Myth Wukong already support it.