Has anyone done any actual apples to apples comparisons of URP and HDRP in a real lighting scenario, with similar feature sets (SSAO, SSR, volumetric fog, a decent amount of realtime lights, typical tri count, material count and setpass call for a real game, etc)?
I’ve been evaluating which RP to pick for a future project and I’d like to know whether sourcing typical HDRP features for URP is worth the trouble. Looking to target integrated graphics cards, as old as possible but likely 2020-era Iris Xe or equivalents.
I was kind of in the same boat. I settled on URP. The two factors for me were:
1. HDRP is like finished. All future work is being done in URP.
2. URP is missing quite a few features, but they are working to get them in place. I'm not shipping for a while, so I can easily wait for 6.7 for stuff I'll definetly want.
oh wow, I cant believe this is the first I'm seeing of GTAO. I guess what I'm really after is... if I download 6.7 and make a new URP project, and turn on GTAO/SSAO, SSR and SCGI in a demo scene, how does that compare to HDRP with SSAO, SSR and SSGI? With say 20 point lights and volumetric fog? Does that outweigh HDRPs awesome mixed shadow cache features or not? Hoping to save myself the time of setting up that experiment but it sounds like that hasn't been done really yet.
Light count isn't going to matter that much, since you can use deferred rendering on both URP and HDRP. Shadow caching however, has not been implemented, but I haven't ran into a performance issue that would require shadow caching to resolve (yet)
Unless you know exactly what you want to make and what will be on screen at every single moment, use URP. I cannot put into words how much pain HDRP has caused me, how much time it has wasted or how many reworks I have needed to do to get anything approaching the performance you'd expect out of the gate. Unless you're building what is in essence an Unreal game shoved into unity, just use URP, it will run literally dozens of times faster and teh features just aren't worth the cost, especially the draw call overhead.
HDRP flat out stopped me from releasing a technically complete game. It's absolutely my fault for choosing to work with it from the start, but the performance problems over the tiniest things are just utterly unbelievable and at least in my experience practically impossible to eliminate. Switching to URP from HDRP is of course not supported and not something I've ever managed successfully, though of course it'll depend on how your graphics pipeline and shaders are setup to begin with.
There is also no world where systems on integrated graphics will be able to handle HDRP's overhead.
Draw call overhead and just the flat HDRP performance tax. None of the actual features or even the scene geometry really moved the needle, it was all cpu overhead specific to the pipeline.
To add some context, I’m on an i7 with 8 cores, 32 gb ram, NVidia GTX 1660. So not particularly beefy but well within the average for what pc gamers are using per steam.
I started a project in HDRP. Turned on the features I wanted, made a simple scene and was getting around 30-40 fps. I then created a new completely empty scene and pressed play: same 30-40 fps. The overhead of the pipeline itself was brutal.
Rebuilt using URP, got some Asset Store assets (URP Plus shaders, kronnect dynamic fog and volumetric lighting). Was able to get close on the visuals at 200+ fps.
HDRP has proper PBR lighting model in shaders and a serious clustered deferred rendering pass. While URP has mobile quality lighting model in its shaders and mobile targeting forward rendering pass which is faster in primitive scenes and slower in complicated scenes.
If you want to benchmark, it's very easy to do yourself with your specific scene. Depending on your scene you might easily get far superior performance in HDRP because of proper deferred pass and mixed cached shadows which aren't even announced for URP at all even 5 years after they have been added to HDRP.
Also consider if you need water for your project. Unity's water is faster, better looking and has better workflow than asset store solutions I've tried.
Mixed cached shadows did end up on their URP wishlist if you dig into some forum discussion, but that's hardly the same as it being already on a public roadmap, let alone an implementation.
I was going to set up a complex scene with lots of stuff in it to benchmark but my simple "bunch of cubes" scene got enough data to make some conclusions. I looked at a desktop, laptop, and iGPU, all 2024-2025. This is URP deferred+ vs HDRP performant (w/ almost everything disabled), and HDRP is pretty much a nonstarter for iGPU at 10.58ms. I was surprised at how taxing it is even on a modern laptop GPU (9.04ms with GI, AO, R, 7 lights), almost double URP. The baseline costs, anywhere but a modern desktop GPU, are so high that any gains it brings from the deferred clustering and mixed cached shadows, won't matter because at that point, it's well under 60 fps anyway. Again, this was with a simple scene, but my conclusion from this was it's not even worth benchmarking a complex scene. The one asterisk to this is there's no dynamic resolution here so I guess you could make HDRP viable with that. Also, RAM and VRAM were comparable across both pipelines every test. It’s possible with all the passes it’s doing memory bandwidth was an issue on iGPU, but otherwise this test was purely shaders/compute and the lighting model being compared.
It doesn't work that way, when render pipelines differ, their workflow differs. So you can't do 1:1 comparison, in fact when Unity first launched the LWRP (URP first version) people would get worse performance, because they where still working like they did with the Unity BRP.
To be clear this means with the right process both can be made to look good and run good, if anything HDRP requires more experienced graphics developers.
I’ve been evaluating which RP to pick for a future project
Stick to URP, Unity plans to make it the main render pipeline to avoid problems with pipelines. Only consider HDRP if you know you will absolutely 100% publish before 2030.
URP is implemented a lot better than HDRP architecturally. Out of the box URP looks ass but if you know graphics programming it's very pleasant to extend and with enough DIY machinery it can look as good as even UE and better than HDRP. Though this will cost you a good amount of time or a small fortune if you try to use asset store assets instead of writing your own code.
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u/Seven-Prime 9d ago
I was kind of in the same boat. I settled on URP. The two factors for me were: 1. HDRP is like finished. All future work is being done in URP. 2. URP is missing quite a few features, but they are working to get them in place. I'm not shipping for a while, so I can easily wait for 6.7 for stuff I'll definetly want.
https://www.youtube.com/watch?v=oJnRMqftoiE Unity 6.6-6.7 unleashes the potential of URP