Hey guys - I'm relatively new to Godot and I hope someone could help me:
I added a few light points to my 2D game, and now it's very laggy.
After checking the visual profiler, it seems Godot doesn't use my GPU at all, only my CPU.
Is there a way to setup Godot to use my GPU as well?
Thanks a lot 
I'm using Godot 4.0.3
Running on Macbook Pro, i7, 16GB RAM, Nvidia GeForce 750M
Hi,
try starting godot with console and load your project. On startup there should be some informations on the used graphics adapter. Maybe this sheds some light on the issue.
Does apple even support nvidia gpus on the metal api? I thought apple had a huge falling out with nvidia over their flip chip packaging quality problems aaaaaages ago and have been on less than amenable terms ever since.
klaas Thanks for your help 
I tried to use Console but there are so many messages and I don't know what any of them means.
Could you tell me what to look for?
Megalomaniak
I'm using a late-2013 Macbook Pro. The graphics card works pretty well on most games I tried to play on it.
So yeah, Apple ditched Nvidia long ago, but my Mac still uses it well on anything except Godot and I can't figure out WHY.
Try this in the command shell to start godot ... this should print more debug. Look out for something like metal, vulkan, gpu or alike. There should be something right after you loaded your project.
/Applications/Godot.app/Contents/MacOS/Godot --verbose
750M is very old. On Windows there are Vulkan drivers, but I don't think on Mac (well Mac doesn't even support Vulkan). Godot uses MoltenVK, which converts Vulkan calls to Metal. But Metal is much newer than your device, and also Apple stopped supporting Nvidia. You can see this article to where to look if Metal is working on your OS. https://support.apple.com/en-us/HT208898
TheLotanos Godot and I can't figure out WHY.
Because godot 4.x is using vulkan and IIRC the mac version would rely on MoltenVK which translates vulkan to metal.
You might be able to run Godot 4.0 on your GPU and force it to use OpenGL, but performance might not be as good as with Metal nor will it have all the 3D features/capabilities: https://godotengine.org/article/status-of-opengl-renderer/#using-the-opengl-renderer
TwistedTwigleg I think it does run OpenGL - this is the message I get when I run the game:
TheLotanos OK, so it's running the compatibility renderer which is indeed openGL but 2 things: 1. the godot 4.x openGL 'compatibility' renderer is still work in progress as far as I'm aware. 2. what's the state of apples OpenGL drivers for your device? OpenGL has been deprecated for years by apple and unlike other platforms it isn't the HW vendor that develops the drivers but apple themselves.
Megalomaniak
A few things - first of all, I really appreciate your help and kindness. thank you!
Second thing - I'm VERY new to this, so most of the terms for mention are foreign to me and I can't understand what it means or what I'm supposed to do from here. If you could try to explain in simple terms what I need to do and/or if there's anything to do but to buy a PC - that would be great.
Third thing - I tried to use "Forward+" and the good news are - Godot switched from OpenGL to Vulkan and started using my GPU!
Bad news - the game is just as laggy 
I guess that Mac users are not able to use any lighting in their projects? What should I do?
It may be that the machine is just too old. It's from 2013 and was a mid-range laptop chip back then.
You can try Godot 3.5 with the GLES2 renderer, it's much faster on older hardware. Otherwise you might have to buy a new machine.
One thing that could be contributing to the lag could be screen resolution. Macs, even older ones, have pretty high resolution screens (often over 2K) and this can be difficult for the GPUs on the machines.
If you lower your screen resolution a bit, you might be able to improve performance some if the GPU is struggling to render. This page has some instruction on how to change it, but the steps may vary based on MacOS version (I just grabbed the first Google result): https://www.digitaltrends.com/computing/how-to-change-mac-screen-resolution/
TheLotanos If you could try to explain in simple terms what I need to do and/or if there's anything to do but to buy a PC - that would be great.
If you can afford a hardware upgrade it's probably worthwhile, whether a newer apple product if you prefer them or a 'PC'(technically macs are that too). But if you can't afford that right now, perhaps as an alternative you can give godot 3 a try. Bonus, there's many many more tutorials to be found for it. No guarantee that it'll work better for you tho.
TwistedTwigleg If you lower your screen resolution a bit, you might be able to improve performance some if the GPU is struggling to render.
There is a viewport property for quarter resolution(think it was called half resolution but halves per axis so effectively quarter res). In the viewports top-left drop-down menu.
Megalomaniak Thank you so much! That was very helpful
TheLotanos
I think godot is not made for mac users and also I hate to say that the apple software is my least favorite one. I think you might need to use godot 3 for lighting until godot fixes the problem.
Try going to project settings, search for gpu and under common, turn on GPU
I have the same issue. But only when i Choose "Compatibility" renderer, not with "Forward+"
and "Mobile" renderer. I don't know for sure if this is an error or by intent, the GPUParticles3D still work in Compatibility mode but when debug i found out that it use CPU...
