Considering jumping ship from HDRP to URP (LWRP). What's the difference now?

I've been using HDRP for maybe 8 months now, having migrated from the built-in renderer back in December. I made this decision mainly to start being able to use Shader Graph and the Visual Effects Graph. However, my project is being build for Desktop + PS4 + XBox1, not for mobile or other platforms. So at the time, I chose HDRP believing it was the best choice for those platforms.

However, it now seems that URP is really catching up in terms of visuals. From the 2019.3 beta blog post (https://blogs.unity3d.com/2019/08/27/unity-2019-3-beta-is-now-available/), it seems like URP will soon support all of the post processing effects I'm using in my game.

I'm not really pushing the envelope in terms of graphics, as I'm a solo-dev here generally building everything myself from scratch. You can get a good sense of my look and feel here:

Spoiler: Video

I'm going for realistic, but certainly not next-gen quality. My biggest concern is whether the game will run well for the most possible people, and it seems that HDRP's requirements limit the audience somewhat.

So I'm debating whether it will make sense for me to switch from HDRP to URP in the near future. But I was hoping to quantify the impact of this decision. I was hoping some people might have answers to some of the following, as it's not easy for me to determine this from the existing docs.


1) Are system requirements for URP lower than HDRP?

HDRP requires Shader Model 5.0 graphics card. Is this also the case with URP? In short, would using URP allow more people to play my game?

2) Should I expect better performance from URP than HDRP in general?

Assuming I'm not pushing HDRP to its limits, would you expect a given scene of similar quality to run faster in URP than HDRP?

3) What major features will I be missing out on with URP compared to HDRP?

It seems that Volumetric Lighting is only in HDRP, not in URP. Are there any other big features I won't be getting in URP? I don't plan on using raytracing, so no worries there, but I rely heavily on Realtime GI.

4) In short, what's the big difference between HDRP and URP these days? Why would you go with HDRP compared to URP?

5) Any horror stories migrating from HDRP to URP? I know HDRP uses a MaskMap instead of individual textures, which will mean a lot of migration changes. Any other major hiccups migrating from HDRP to URP?

Thanks.

 

There are tons of limitations with LWRP to consider:

• Maximum of 8 pixel lights EDIT: Apparently this is no longer true.
• No pre-computed dynamic global illumation (this has big influence on visuals)
• Reflection probes are sorted per objects and don't support blending
• Not sure on this one, but I think only the directional light can emit dynamic shadows
• No Motion Blur, no SSR, no Ambient Occlusion
• No volumetric fog
• No subsurface scattering
• No realtime area light
• No high-LUX HDR support
• No iridescence
• No double-sided transparent render (this maybe be done via Shader Graph)
• No built-in decals (this may be hand coded in LWRP)

...and much more.

The main advantages of LWRP is that it is fast and currently super stable. It is also closer to what we're used to in term of content creation inside Unity.

Still, in a realistic context, I'd certainly work with HDRP since there are features that I cannot live without, such as Dynamic GI, AO and volumetric fog.

EDIT: Of course some of these features can be hand coded into LWRP, but I don't think that this is the point here. Out of the box, HDRP is much more cutting edge in term of visual accuracy than LWRP, and that is why both pipelines exist.

 

Are you aware that Enlighten support is being removed from HDRP?

https://forum.unity.com/threads/enlighten-deprecation-and-replacement-solution.697778/

 

Of course, in 2023 for already-supported platforms, and replaced by something else in 2021.

 

Not sure where you are getting 2023 from? 2019 LTS and not touching 2020 versions of HDRP?

 

Thanks for breaking it down like that. I didn't even notice that Realtime GI wasn't supported in URP, which is definitely a dealbreaker. Thanks for pointing that out. HDRP it is.

It would be nice if Unity would author a comparison table for URP and HDRP, kind of like one of those tables that shows you what features are supported in each higher tier of a product, so that users could quickly view the differences between them. Basically one of these tables, but for HDRP and URP features: https://store.unity.com/compare-plans

 

All fairly wrong now, check latest blog for Universal, you get mot of the post effects, almost no light limits and the rest is available via shader graph.... so Universal is a big deal now, and a big improvement and a candidate for actually replacing ye olde built-in.



https://blogs.unity3d.com/2019/08/27/unity-2019-3-beta-is-now-available/

edit: I know technically it's right but it won't be going forward.

 

Try to fact check first

 

Which ones were wrong? Most on the list were somewhat accurate (altho I wouldn't promote enlighten support when it's not been great on HDRP and it's getting removed from the 2020+ releases), I see they added motion blur now (do they finally have motion vectors in URP?).

 

I said "fairly wrong" in context of original poster not having seen Universal and not seeing how far it's come. You can approximate pretty much everything now via the graph in Universal... The light limit on screen is way better too.

 

From that list, these are all correct

I would assume once the deferred render is added to URP it will get some of the more advanced Post Processing effects that uses compute shaders - https://github.com/Unity-Technologies/ScriptableRenderPipeline/commits/universal/deferred

 

Yeah, I was mainly comparing the featured listed in that blog post, and found that it nearly covered everything I was already using in HDRP, and figured maybe URP would be sufficient. I merely assumed Realtime GI was supported in URP, because I figured it was simply part of Unity (as it's in the built-in renderer). I probably would not have made this post at all if I'd realized beforehand that URP didn't support Realtime GI.

It makes me wonder now, though, whether Realtime GI is possibly coming to LWRP. There's this post (https://forum.unity.com/threads/lwrp-fully-dynamic-lighting-and-gi.611812/#post-4100209) from January stating that it's planned. So maybe some day.

Mainly my concern was whether I could have a wider end-user base for my game if I switched to URP, and whether a similar scene in URP would tend to run at a higher framerate than under HDRP. I'm having second thoughts now about whether my game really needs the bells and whistles of HDRP, given how far URP has come. But I guess until/unless Dyanmic Realtime GI support is added, that question will remain moot.

Anyway, thanks everyone for all the feedback and help so far.

 

Keep in mind that since then, they announced the deprecation of Enlighten.

Enlighten deprecation and replacement solution

So I think its more likely they will focus any URP realtime GI efforts on their new replacement GI system that will be under development in the year+ ahead.

I do think it is easy to speak of GI too generally and miss all sorts of detail though. I'm no expert, but I note that there are quite a lot of different GI sections and capabilities listed in the built in renderer-URP comparison matrix:

https://docs.unity3d.com/Packages/c...l/universalrp-builtin-feature-comparison.html

 

Thanks. Seems I also completely missed the upcoming deprecation of Enlighten. I'm reading through that thread now. I haven't yet determined conclusively from that thread whether a realtime GI solution will be in place for 2020.1, when Enlighten is removed from HDRP. Hopefully so... I'll be keeping an eye on that. Thanks for the heads up.

 

They are all fairly right, actually.

The 8-lights limit is the only one that is no longer true and thanks for pointing that out.

To the "Considering jumping ship from HDRP to URP (LWRP). What's the difference now?", the answer is that a lot of features are HDRP-exclusive. The average user cannot code SSR or decals into the universal pipeline. The same is true for realtime area lights, iridescence, subsurface scattering, volumetric fog and so on.

...another thing is realtime raytracing, which is currently only available with HDRP.

The bottom line is that if you are making a realistic game, and that visual accuracy is a big part of it, HDRP is a better option than the Universal Pipeline.

 

That's really the tough question to answer, for me anyway. The visual style of my game is realistic, but not hyper-realistic or photo-realistic. This is mainly due to the limitations of my expertise in modelling, and my lack of an artistic style. It's hard for me to judge whether the relatively simplicity of my visuals really necessitates the power of HDRP, or whether it would mostly look the same using URP. That's obviously not a question anyone but me can really answer, and it comes down to what kinds of effects I want to include.

I think it turns out my main concern is moot. This Steam Hardware survey page (https://store.steampowered.com/hwsurvey/videocard/) says that about 94% of users have a DX 11 or higher, which tells me that up to 94% of users can run HDRP games. (Maybe not at great framerates, but it's possible.) So that's probably comfort enough for me. I'll stay on HDRP for now, and not worry too much about the stragglers with DX 10 and under who won't be able to play my game.

Thanks again for all the information and help in this thread.

 

Just the fact that Unity samples (ex) run beautifully on PS4 is a good pointer that it is being developed with scaling to lower end hardware in mind. Our game comes out in a couple of years, and PS4 hardware at this point will be comparable to the median laptop.

But I have to say that HDRP is quite harder to develop on than built in or URP. There are some extra steps in the making of all assets and scenes compositions. As it is our second game and that we have decent funding, it is acceptable, but it is something to think about.

If that is true then I'd start with URP, if I were you.

 

Maybe. Certain features of HDRP need the right art assets to get the most out of, but others dont. Depending on the desired style, there could still be some HDRP lighting system, post-processing effect, volumetric fog, or shader feature that really makes a good difference.

 

what is this URP post effect?? atmospheric scattering? volumetric? i can't see this fx on URP postpro effects? [2019.3 URP] how to do that?

thanks.

 

As this was a central part of this discussion - please note that the "light limit per object" hasn't increased at all. It's still 4 (and supposed to go to 8 for non-mobile targets). Only the "light limit per scene" has increased, which is only relevant in giant scenes where at most 4 lights shine on the same thing at the same time.

 

To be clear, 7.11 (which isnt finished/formally released yet) changelog:

https://github.com/Unity-Technologi...unity.render-pipelines.universal/CHANGELOG.md

 

Most likely these are a bunch of stretched planes / faked god rays.

There is no built in volumetric fog in LWRP.

 

so, what about this??



fake info on Unity blog??? :]

 

I never said you couldn't have post processing in the Universal Render Pipeline, I said these:

• No Motion Blur, no SSR, no Ambient Occlusion
• No volumetric fog

Bloom, tonemapping, anti aliasing, depth of field and so on work under the URP.

 

When volumetric fog is ported to URP I will upgrade from default, its such a nice feature that can make a game stand out.

 

Why?
Always ask why. What does RTGI bring to YOUR table?
How is that different from non dynamic GI?

in my opinion, Realtime GI is certainly an overhyped feature. So much so that Unity deems it pretty much irrelevant and marked is as deprecated. I know there will be many to come to its support. Opinions, opinions, but I would still like to see how it makes a significant difference to a project before calling it a 'dealmaker'

 

If these were your concerns I would think they are unfounded. DX10 support is the least you should care about. Not even Microsoft cares about DX10

 

For me, Realtime GI adds a level of realism that just isn't there without it. In my game, there's a lot of moving lighting, such as swinging lamps, and other light that moves from place to place. Realtime GI just makes that effect much more alive. Here's a little video I made a while back showing the difference.

It might not be super obvious from the video, but to me it's very noticeable in-game. It feels like the difference between playing a modern game, and one from 15 years ago.

Anyway, it's fair to question these things, but for the aesthetic I'm going for, Realtime GI is pretty important.

 

Can I get some help on this one? For point lights I get "Realtime shadows for point lights are not supported. Either disable shadows or set the light mode to baked." There's no longer an option to change the rendering mode to deferred in the URP settings. The same result occurs for spot lights, but without a warning.

 

Deffered is not yet supported in URP, so you won't get these shadows unless you bake them.

 

Point light shadows are "in research" at the moment (see https://github.com/Unity-Technologi...on~/universalrp-builtin-feature-comparison.md)

However if you could use spotlights (with a wider angle perhaps) then these would actually be higher performance than a point light shadow (which is actually 6 shadows to render if not dual paraboloid shadow mapping!)

So for now use spotlight to emulate a point light.

 

It’s all so confusing, can we please get a side by side comparison table Unity.

With info on what to be added

 

https://docs.unity3d.com/Packages/c...l/universalrp-builtin-feature-comparison.html

 

THANK YOU

 

There are ways you can achieve what you showed differently. If you think it is GI that does that for you, It is possible that you misunderstand it. You can achieve exactly what you showed with increased baked GI intensity and a cheap soft light.

 

I'm happy to be shown wrong on this, but I don't see how the same effect could be achieved without Realtime GI. The specific attraction of Realtime GI is that the light bounces outside of the direct influence of the light. For example, using a spotlight without Realtime GI, the only pixels that will receive any light from the light as it moves are those within the cone of the light. But with Realtime GI enabled, the light will bounce and hit other nearby walls, the ceiling, etc, in a much more realistic way.

But, it's entirely possible I don't know the best way to set up simple baked lighting to achieve a similar effect. Do you know of a video or something that demonstrates the the light bouncing effect that doesn't use Realtime GI?

In either case, it's probably moot given another feature of my game: The lights are often turning on and off, and on many cases, flickering on and off as the power blinks out periodically. Sometimes the lights completely go out, and it's pitch black for a moment. I don't know of any way that baked lighting can handle that sort of thing. So, this along probably keeps me using Realtime GI, even if I didn't prefer the visual appearance of the bounced light.

 

Of course not, otherwise you would have implemented it.

 

Why don't you show us, Soleron, instead of just saying it's possible without evidence? I really want to see you do this so I can learn from your example. If it IS possible to get those effects without realtime pre-computed GI, and you have some secret knowledge, we'd all benefit from it. I really want to see evidence of this so I am make my game even better. Can you provide that evidence?

 

For bounce, some games have done the soft fill light thing. HDRP even supports adjusting lights to remove the hard point for a fill light effect. The developers of HDRP explained it could be used for a fake GI effect on these very forums, if you care to search.

This is achieved by placing soft lights near walls you'd expect bounce, then linking that to the main light. It's more labour intensive but is what games do to save perf. It generally looks just as good but you pay the price of having to manage this extra authoring work.

While soleron was a bit abrasive in their reply, it's no less correct for a large amount of games, and is a possible approach suggested by one of the authors of HDRP.

Currently, URP doesn't have a soft fill light option, but for me, I can just use shadergraph to add an attenuated non specular light cheaply to a shader for things like this. If i was smarter I'd probably look at a form of spherical harmonics, but I don't have time for the authoring that would surround it.

Just a bit of additional info I've collected over time.

 

ngl it looks like you just made the scene brighter

 

All I know is there is no way I can get this from URP only HDRP,

 

I have been playing with HDRP and URP (VR). I can say that here is HUGE difference in lighting. I really, really want to use HDRP but unfortunately, at least in my case, I can't justify the awesomeness of HDRP because of the massive performance drop. URP on the other hand is insanely more performant and looks OK too (definitely better than the standard, soon to be legacy). Performance requirement for HDRP (again from my little tests) seem to nearly doubled.

I really wish for these HDRP lights though, this is the single most reason why I want HDRP. See the screenshots. I only spent few minutes on both of these, but HDRP is far superior in quality. URP seems dull in comparison, also real-time point lights in URP does not support shadows. If anyone have some tips to getting URP lights (e.g. point lights with a glow) at least closer to HDRP please do let me know.

GTX 1080
URP: about 6-8m/s
HDRP: about 15m/s






Edit: Both of the pics you see here are without post processing. I have come to learn that URP does look pretty good when you apply some Post Processing effects -something to think about.

 

Man that HDRP does looks nice , I’m in the same boat. I can’t get HDRP running at a decent frame rate Currently I have the attitude that my inexperience with HDRP is most likely the root of my performance issue

 

With URP, not having point light real-time shadows is a bummer too. I really wish there was something in between instead of all or nothing. I have tried to use HDRP with low settings, even with everything turned down/off I get poor performance compared to URP. I feel like for outdoor, brighter scenes URP is great. But indoor scenes that tends to be darker, URP just looks ugly.

I guess the good news is it's not impossible or even that difficult (I don't mean time, I mean what you need to do) to switch to HDRP when it is bit more stable.

 

It seems you have been at this (URP) far longer than I have. Do you happen to have any other insights/info or guides that you know of to getting URP somewhat closer to HDRP? I can't seem to get the colors/surfaces to pop or make it look more a live (the best I can describe) as with HDRP. Thanks!

 

I can't count the number of times one of your posts have helped me over last several years.Thank you!!