[SOLVED] Massive Performance Drop from 1.60 to 1.61 with Clustered Lighting


Switching from 1.60 to 1.61 causes a huge performance drop to a few frames a second. Happens in simple scenes with spot lights and Clustered Lighting enabled.

Directional Lights and disabled Clustered Lighting works fine.

Happens on Win11, Firefox and Chrome.
Also iOS/Safari seems to be affected


Thanks for your help.

  • Tom

I can confirm the same, here is a scene with all shadows disabled, just 1 directional light and a big number of point lights (50). The performance hit is massive indeed in 1.61:



@mvaligursky @yaustar any idea what is causing that?

Not yet, but I’m investigating.

Hi @TRT - I cannot reproduce a performance issue on your project - I tested in chrome on windows 10 and safari (apple chip) and that runs very fast.
Are your graphics drivers up to date?
How about this example? Is it slow for you? PlayCanvas Examples

I managed to reproduce this, it seems the Standard Material shader is running some complex operation on lit pixels, here is repro project:




The performance hit may not seem massive (~2ms higher), but if you have multiple materials in view affected by a clustered light (lots of pixels) then it becomes massive indeed.

Added a bug issue: Performance drop in v1.61 when using clustered lights · Issue #5086 · playcanvas/engine · GitHub

Maybe it can help.

Here and here

If I understand correctly before the commit we had 4 times less texture lookups + storing 1 light per 1 texel may be less cache-friendly.

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Having the same frame drop on my project. Difference is huge

we’ve just release 1.61.2 with the fix:

and will be promoting it to the Editor shortly as well.

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This is now released to the Editor (1.62.2)


I can confirm, performance is back with 1.61.2. Thanks a lot!

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