# LightmassReplace node not working with GPU Lightmass? **URL:** \ **Category:** Rendering\ **Tags:** building-lighting, gpu-lightmass, unreal-engine, Global-Illumination\ **Created:** [May 6, 2022, 6:40am UTC](https://forums.unrealengine.com/t/lightmassreplace-node-not-working-with-gpu-lightmass/550200 "2022-05-06T06:40:05Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Pantoth](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/pantoth/32/1194538_2.png) [@Pantoth](https://forums.unrealengine.com/u/Pantoth)\ **Post date:** [May 6, 2022, 6:40am UTC](https://forums.unrealengine.com/t/lightmassreplace-node-not-working-with-gpu-lightmass/550200/1 "2022-05-06T06:40:05Z")
Hi everyone! After switching from good old CPU Lightmass to GPU Lightmass (and some tinkering with Luoshuang’s GPU Lightmass) I’m at a point where I’m happy with the result. But what I discovered recently: The really great LightmassReplace material node doesn’t work like before (or even doesn’t work at all) with GPU Lightmass? ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/5/4/85476abb2d0ae62af0b766b4ce1bc68bba984e08.png) That node really helped getting better GI in dark(er) rooms - easy and fast. For now I’m switching materials before and after I bake the light, but are there any plans on adapting that node or maybe some additional node that works with GPULM? Thanks! ---
**Author:** ![Tomasz\_Klin](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Tomasz\_Klin](https://forums.unrealengine.com/u/Tomasz_Klin)\ **Post date:** [March 8, 2024, 8:28am UTC](https://forums.unrealengine.com/t/lightmassreplace-node-not-working-with-gpu-lightmass/550200/2 "2024-03-08T08:28:41Z")
Node RayTracingQualitySwitchReplace do what you need ![image](https://d3kjluh73b9h9o.cloudfront.net/original/4X/1/a/7/1a776166e772f2b6911db094b3b1ec327efc5b2b.png)