Optimize LOD & Improve FPS in Unreal Engine 5 UE5

greetings gentlemen and ladies uh in today's video we are going to learn a little bit about what i learned about yesterday and that is a setting lod levels for optimizing fps and performance my fps is not very good here but it's better than it was and it could be dramatically better if you want to really tinker around with it i just kind of wanted to create a workflow for now using these qixel mega scan trees which are just beautiful but also very high detail in their original form so here's a little bit into lods and how they work and how to how to deal with them how to how to adjust them let's see i'm going to open up my black older tree different than the black adder which is mr bean or something like that black adder is that what i'm thinking i don't know anyway here's here's lods here's lods in a nutshell so right now what i've done in order to sort of shortcut my workflow and just get a reasonable lod that i can actually move this used to be 6f fps now i'm like 20 or whatever right but this used to be extremely extremely uh sluggish so what i've just done right here over over in the minimum lod is set the minimum lod to 2. all right so minimum so lod 2 if you take a look at your lod picker you can choose which lod you want to work on and that's what the lod picker is all about so lod 0 shows right up here in the in in the top left corner of the screen how many triangles the model is at lod zero lod zero means no reduction it is full full uh detail full detail on your model um and basically as you cycle through lod zeros the highest lod six in my case would be the lowest detail and you can you can adjust how you want these to perform now they do automatically have um a built-in sort of distance auto compute lod distances that is a thing that you can do but unfortunately unfortunately that is not always the most optimized option all right so let me show you really quickly uh what i'm going to do here i'm just going to actually set that back to lod 0 and you can see right now i've got 423 000 triangles in the model as i back up a bit further if i actually switch to lod auto you can see the lod in the top left corner of the screen is actually based the the resolution of the model that you're looking at is based upon the current screen size it's not distance that it's based on but it's based on current screen size so right now it's got 120 percent size 1.2 here's a 90 percent size here as we get back to 50 size of my screen uh you can see the lod automatically switches to one which reduces the triangles down to 200 and 11 000. as i back up even further now we're at uh screen size 20 give or take 22 triangles have been reduced down again to 105 000. so uh that that is you know basically how auto lod is supposed to work and what auto lod or what lod settings basically do is they allow the model to be shown with fewer and fewer basically triangles right now so right now this is like very high detail right but if i switch this over to let's say minimum lod one now you can see i've got two hundred and eleven thousand triangles there's not much difference there you couldn't really see what happened too much right so the led zero led one not much difference there because lod doesn't affect textures as far as i can as far as i can tell it only affects the number of geometry like the number of triangles or polygons in the model so you can adjust this and try to find what works best for you here's lod 2 which actually reduces the model count in this case i think by uh down to 25 polygons and you can see that's still basically pretty good there's a little bit of weirdness here and there but for the most part that's pretty pretty good not too bad right there i've got a little bit of a weird triangle situation happening but probably for the most part that's not even going to be noticed and certainly it's not going to be noticed at this distance right so what you are going to want to do for for creating a sort of crude workflow the easiest way to do that without without totally optimizing and i'll talk about that in just a second but the easiest way to create a crude workflow is to figure out a good minimum lod and basically cap out what this model will lod or the minimum what the what the highest resolution lod will be so if i need more performance i might want to drop the the minimum lod down to three and then it will never show higher resolution higher lod than three doesn't matter what the auto lod will still work as you distance out will it oh no sorry i'm set to what am i set to well i think it's i'm pretty sure it still works as you distance out maybe i just need to go further yeah there we go lod four uh now where's where's my tree i lost my tree okay we'll be right back hang on a sec i went too far okay so the auto lod will still work but the cap for the lod will be set to whatever the minimum lod is now if you really want to get into optimization like i say this is your your quick and dirty work workflow option right here you can just set the cap lod and that way your game will actually run so i've got my cap right now i think set to lod 2 and my game actually runs although the fps is not great i might might even want to set that cap down a little bit lower to be more functional but anyway so now here's the other here's the other option you have if you want to configure what lod shows uh depending on basically distance how big that that that mesh is on your screen you can do that and what you need to do is first untick here where it says auto compute lod distances all right so now you'll have the option where is it somewhere around here looking for looking for no not there we're looking for the reduction settings here we go under lod0 so what you're going to want to do is all of your lods from your lod picker right now we're looking at lod auto so let's take a look at lod 0 which is your top top resolution one uh and then of course let's say for example lod lod1 right so if we want to change currently lod1 is set to a reduction of 50 right so the normal number of triangles in here is about 422 thousand right now the lod-1 is set to 50 triangles if i change this down to 10 oops if i change this down to 10 and i was actually looking at lod-1 oh yeah led is below the minimum of three so i think i actually need to uh i think this is because i've got different lods that are set lower and higher so let me actually just uh let me just say here so lod auto i'm sorry lod 0 ah lod 0 oh right because so actually i'm just going to put that back up to its maximum just for the sake of taking a look here lod 0 nope sorry lod 0 custom advanced where where were we things jump around there we go close that all right so lod0 here we have lod0 now we have lod1 which i have currently at 35 triangles there's 50 uh what are we currently looking at we're looking at lod1 yeah we're looking at lod1 so reducing the number of triangles here should why is that why is that not working come on game uh oh maybe i just need to click apply changes that's probably what i'm not doing probably and that's the thing when you click apply changes now um this i think has a bit of loading time so we might might be staring at the screen for a second at least on my setup for some reason this seems to take quite a long time to do so i'll pause the video here and we'll come back once that's set okay we're back and there we go there's the there's the triangle reduction at 35 is now 148 that applied changes just takes ages on my my computer i don't know why it takes so long took about two or three minutes um to to set anyway that is a look at how to configure uh your various lod levels for various distances and then basically what you would do is you would go through all of your different lods and figure out what size you want them to be what here's here sorry i missed one part here's the screen size right for lod 2 screen size that it needs to be so and you can figure out what your current screen size is up here right so right now it's 1.1 so 0.2 would be right around 0.27 would be right around here so once the player got to that distance that screen size 0.27 then we would then we would swap over to lod 2 which would reduce the triangles by 25 percent in this case or 225 percent of the base model log0 um yeah and that's that's basically it in a nutshell you go through all your lods that you want to do and you uh set what distance you want them to be you can see how far you are away over here and then you set the reduction of triangles you want at that distance and you basically apply and continue um my question is do you need to click apply every single time you make a change or can you apply everything all at once i don't know i'm not sure i've just figured this out the other day that's why i'm making a video so i don't forget or when i do forget rather i'll be able to come back yeah okay it looks like you can set all of your distances at once and then you can apply all those changes okay hope you guys have enjoyed this video and future me i hope this was helpful for when i forget all right

Channel: Werewolven

Views: 30,578

Keywords: game development, game dev diary, indie game, developer diary, indie game development, game dev log, unreal engine

Id: AxSOPid9ES8

Length: 10min 6sec (606 seconds)

Published: Thu Apr 14 2022