I was wondering why the spawn rate in my particle system is so much lower than what should be spawning. The second half of particle counter in the viewport reflects the ‘desired’ amount of particles but the amount playing is a fraction of it (typically 1/4).
i.e. With a lifetime set to 1 second, and the Spawn Rate (Dist Float Constant) = 10, the counter still only reads 3/12. This includes using a GPU TypeData.
I can jack up the spawn rate but it still only remains a fraction of the desired amount. I’m afraid to live with this for fear that when it’s played on someone else’s system the particle rate will lurch into an undesirable amount.
In case it’s relevant, when the Detail Mode is set to ‘High’ all the particles disappear in both the sub editor and the main editor viewports. It’s currently set to Medium and the Low setting doesn’t seem to have any effect on this issue.
Hmm, Id need to see some settings, can you make me a screenshot of the required/spawn/lifetime nodes as well as what is being spawned (if its not nda) the more shots, the merrier.
Worst case, just upload a few to imgur or something and link the album
I am asking this because it can be many things.
It can be a very short lifetime, resulting in only a few purrrtyicles alive at a time.
It could be LOD’s, which a lot of people seem to accidentally press.
But it could also be a weird spawn rate and spawn amount.
so… the more I see, the easier it is for me to explain whats going on
I was able to eek out a higher percentage by adjusting the Engine Scalability Settings. By default everything was set to Medium so I lowered unnecessary settings and elevated the effects to Epic. This brought the percentage up a little, but not nearly enough for proper authoring.
Overall this adjustment improved the amount of particles being drawn but it still never renders the full amount. Here are some examples of what happens when the lifetime is adjusted:
Adjusting ‘Effects’ within the Engine Scalability Settings to Medium causes the drawn particles to drop significantly. You can see in the following image by how much. BTW, lifetime was returned to the amount in the first image but nothing else was changed:
I’m thinking my computer is most likely at fault. It has tons of memory and a decent pack of processors but I’m getting a warning about my GPU driver when booting the editor. Due to the image limit per comment I’ll have to follow this issue with a proceeding comment.
I’m also going to run some tests with different texture types and see how that affects these issues. Hopefully I’ll find a work-around.
Okay, to follow up on my previous comment there are definitely some issues with the GPU when booting the editor:
I’ve yet to unearth what these issues are, but obviously this might be causing the issues occurring with the particles.
Here’s the GPU when the editor is opened but not in focus:
The following is what happens when I put the editor in focus without any particles in the level. Restoring the particles doesn’t effect this percentage:
However, the frame rate skyrockets without particles in the level when but as soon as particles are present the frame rate tanks:
I’m not sure if the amount of Memory is correct. It seems low to me, so I wonder if there’s a way to get more for UE while dropping how much the GPU is being taxed?
I’ve tried several ways of updating the drive (local install attempts as well), but nothing works. I always get this result:
Computer specs:
Windows 7 64-bit (SP1) bootcamped on a 2009 MacPro Tower
Well… first off.
UE4 is mainly dx11, it does work with dx 9/10 cards, but the results will be sub-par, and in some cases might mess up results. So that could (with capital could) be one of the issues at hand.
As for the distribution, try setting it to 10-15, which is even low for current day spawning rates. (for stuff with low lifetimes) You can also set it to constant instead of float uniform.
But as someone who is lucky enough to always run ue4 on a high end computer its only a guess for me what could result in low spawn counts on lower end rigs.
might wanna wait untill someone with a lower end rig/experience with lower end rigs/epic dev replies.
So I went to the Nvidia site and looked into the specs of my Quadro. It states the GPU is a Dx11 card. I also verified that Dx11 loaded on my workstation.
Okay, well that settles that. Dx10 it is. I’ve noticed particle systems using complicated materials exhibits spawning difficulties. When creating smoke with a simple material, the percentage is much higher, but the flames has a heavy material. It appears my computer just can’t handle materials with a lot of calculations in it. Bummer.
Distribution/spawn rate was raised. The accompanying image is the third one down in my first response with pics … which also includes a couple of other pics of the requested spawn rate in various configs. Increasing the spawn rate from .4/.6 to 5/5 increased the total particles being drawn but it didn’t affect the overall percentage that I’m trying to remedy. I’m certain you’re correct in regards to my card is most likely the main suspect.
Following are pics of the both the Required and the Spawn Modules in their entirety. Hope this is what you’re requesting to examine:
I believe I can shed some light on this subject a bit more. So we have determined your GPU is the Mac version of the Nvidia Quadro FX 4800 which is a DX10 Compatible card. This also means you are using the SM4 shader model. The default for DX11 uses the SM5 shader model which is the current most up to date model used in the engine.
As you have pointed out for yourself, I believe your issue here is the hardware you are running. Direct3D version 10 is directly equivalent to all OpenGL 3.x versions. Direct3D version 11 is similarly equivalent to all OpenGL 4.x versions. In our Hardware and Software Specs documentation we recommend an OpenGL 4.1 compatible graphics card. This is because compatibility for earlier versions cannot be guaranteed to work as they are a bit older and are becoming less supported. I do not normally suggest upgrading a users machine/hardware unless I believe it to be the issue, and in your case, this has the potential to cause issues across your projects that you create.
With all of that said, I would set your distribution to a constant uniform so there are less variables on Spawn Rate. Then take a look at your Project Settings > Rendering > Frame Rate, and see if you are using any frame rate smoothing or have a min and max frame rate set. This could be essentially limiting the rate of your spawning particle system.
Let me know if you have further questions or need additional assistance.
Hi Andrew,
Thanks for explaining this. I’m not the most savvy person with these kind of issues so it’s helpful to gain a little insight whenever it comes my way.
Anyway I was hoping to find a replacement GPU, but according to this list [Mac computers that use OpenCL and OpenGL graphics - Apple Support] it appears my MacPro isn’t compatible with any of the 4.1 compliant GPUs. At least that’s what I’m assuming. Of course the very next gen of MacPro Towers are
I’m going to head down to the Apple Store—oohhh lordy kick me in the head—and see if they have any recommendations. My main question will be whether or not a compatible 4.1 GPU exists (i.e. Apple ATI Radeon 5770). I hope so since it would a lot le$$ than getting a new computer
