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Bunnymark GL in Jai – 200k sprites at 200fps [video]

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Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#51

Post by gmueckl »

aappleby wrote: post #41

Very rough guesstimates: 200000 * 200 * 2 = 80M tris/sec 200000 * 200 * 32x32px = 40 gpix/sec (if no occlusion culling) Neither of those numbers are particularly huge for modern GPUs. I'd wager that a compute shader + mesh shader based version of this could hit 2M sprites at 200 fps, though at some point we'd have to argue about what counts as "cheating" - if I do a clustered occlusion query that results in my pipeli…

This demo program is obviously FPS limited in some other way - it's locked at 200fps from the start. The true limits are higher than what is shown.

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#52

Post by farzher »

aappleby wrote: post #41

Very rough guesstimates: 200000 * 200 * 2 = 80M tris/sec 200000 * 200 * 32x32px = 40 gpix/sec (if no occlusion culling) Neither of those numbers are particularly huge for modern GPUs. I'd wager that a compute shader + mesh shader based version of this could hit 2M sprites at 200 fps, though at some point we'd have to argue about what counts as "cheating" - if I do a clustered occlusion query that results in my pipeli…

writing 100% of the code on the gpu can render 10,000,000 triangles per frame at 60fps ... even in the web browser! (because there's no javascript running) https://www.youtube.com/watch?v=UNX4PR92BpI

but yes, that's cheating, since it's impractical to work with

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#53

Post by gmueckl »

HWR_14 wrote: post #42
iliketrains wrote: post #22

Earlier quoted context omitted.

Rendering only one large triangle can be faster than two. First one triangle needs less memory, less vertex processing, etc. Second, modern GPUs render pixels in groups of 2x2 up to 8x8 "tiles". If only one pixel from this group is part of a triangle, the entire group will be rendered. When two triangles form a quad, the entire area along the diagonal "seam" will be rendered twice. The smaller quads you have, the mor…

I disagree, with the exception of the case you link to where half the pixels are outside the viewport or maybe where a sufficient percentage are outside the viewport. > When two triangles form a quad, the entire area along the diagonal "seam" will be rendered twice This may be true, but I'm pretty sure that this is more than made up for by the additional pixels in the single triangle circumscribing the quad. In fact,…

It depends on the size of the sprites in this case. Small sprites will benefit from being drawn as single triangles.

These "shadow" pixel shader invocations are a very real pain when it comes to rendering highly detailed models. The hardware rasterization pipeline can't cope well with huge amounts of really tiny triangles. That's the reason why UE5 Nanite uses a software GPU rasterizer for the high geometry density sections of a model - it's faster! Large area primitives will be rendered normally AFAIK.

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#54

Post by farzher »

adamrezich wrote: post #9
farzher wrote: post #5

Earlier quoted context omitted.

it's a lot of fun! jai is my intro to systems programming. so i haven't tried this in C++ (actually i have tried a few times over the past few years but never successuflly). this is just a test of opengl, C++ should be the same exact performance considering my cpu usage is only 7% while gpu usage is 80%. but the process of writing it is infinitely better than C++, since i never got C++ to compile a hardware accelerat…

the official rendering modules are a bit all over the place atm... did you use Simp, Render, GL, or handle the rendering yourself?

just used raw GL calls from #import "GL". although i did #import "Simp" as well for Simp.Texture and Simp.Shader, which Simplified things quite a bit

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#55

Post by johnnyanmac »

farzher wrote: post #48
daenz wrote: post #27

It's been awhile since I've done game engine work, but is this impressive? The first thing that comes to mind is they're using instanced rendering. This allows the CPU to only deal with 1 sprite, while telling the GPU to render multiple instances of the sprite, and use a GPU buffer to find each sprite's transformation matrix. All the CPU has to do is update that mmap'ed buffer with new position information (or do som…

you're not missing anything, it's not impressive. i was just checking how fast computers are and sharing the results. my original title was "an optimized 2d game engine can render 200k sprites at 200fps" but the mods changed it to match my youtube title (which made it a lot more popular). and the fact it's written in jai isn't relevant, it's just what i happened to use

> and the fact it's written in jai isn't relevant

I figured it wasn't given that you were showcasing a GL project. But nonethees disappointing as someone curious as to whether or not the language helped in indirect ways with how you structured your project and if you feel you could scale it up to something closer to production ready. That did seem to be the goal of Jai when I last looked into its development some 4 years ago.

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#56

Post by farzher »

johnnyanmac wrote: post #55
farzher wrote: post #48

Earlier quoted context omitted.

you're not missing anything, it's not impressive. i was just checking how fast computers are and sharing the results. my original title was "an optimized 2d game engine can render 200k sprites at 200fps" but the mods changed it to match my youtube title (which made it a lot more popular). and the fact it's written in jai isn't relevant, it's just what i happened to use

> and the fact it's written in jai isn't relevant I figured it wasn't given that you were showcasing a GL project. But nonethees disappointing as someone curious as to whether or not the language helped in indirect ways with how you structured your project and if you feel you could scale it up to something closer to production ready. That did seem to be the goal of Jai when I last looked into its development some 4 y…

jai's irrelevant to the performance here, but it's very relevant to how easy this was to make. i'm not a systems programmer. i've tried writing hardware accelerated things like this in C++ but have failed to get anything to compile for years. the only reason i was able to get this working is because of jai. this is my first time successfully using openGL directly, outside of someone else's game engine

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#57

Post by bob1029 »

farzher wrote: post #49
bob1029 wrote: post #10

Earlier quoted context omitted.

> We need more of this approach. 1000% agree. I recently took it upon myself to see just how far I can push modern hardware with some very tight constraints. I've been playing around with a 100% custom 3D rasterizer which purely operates on the CPU. For reasonable scenes ( single thread. On a 5950x, I was able to support over 10 clients simultaneously without any issues. The GPU in my workstation is just moving the f…

> One fun thing I discovered is just how low latency a pure CPU rasterizer can be compared to a full CPU-GPU pipeline i'm definitely going to have to test that! always trying to minimize input delay

I think it can reduce input delay enough to change streaming gaming economics, but the current state of cloud economy makes it difficult to scale in practice.

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#58

Post by 2pEXgD0fZ5cF »

KapKap55 wrote: post #35
DantesKite wrote: post #11

Earlier quoted context omitted.

I thought Jai wasn't released yet. Are you a beta user or did he release it already?

It isn't released. That said, from people I know, it seems like you can just ask nicely and show some interest and he'll let you try it out.

That only applies if you are a known name (probably being known among his fans works too), or have somebody in his circle vouch for you. Regular people don't get in.

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#59

Post by gpderetta »

bob1029 wrote: post #10
xaedes wrote: post #6

Nice demo! We need more of this approach. You really can achieve amazing stuff with just plain e.g. OpenGL optimized for your rendering needs. With todays GPU acceleration capabilities we could have town-building games with huge map resolutions and millions of entities. Instead its mostly only used to make fancy graphics. Actually I am currently trying to build something like that [1]. A big big world with hundreds o…

> We need more of this approach. 1000% agree. I recently took it upon myself to see just how far I can push modern hardware with some very tight constraints. I've been playing around with a 100% custom 3D rasterizer which purely operates on the CPU. For reasonable scenes ( single thread. On a 5950x, I was able to support over 10 clients simultaneously without any issues. The GPU in my workstation is just moving the f…

Did you consider using an existing software rasterizer, like Mesa llvmpipe? Or part of the challenge was writing one yourself (nothing wrong with that)?

Re: Bunnymark GL in Jai – 200k sprites at 200fps [video]

#60

Post by jcelerier »

aappleby wrote: post #41

Very rough guesstimates: 200000 * 200 * 2 = 80M tris/sec 200000 * 200 * 32x32px = 40 gpix/sec (if no occlusion culling) Neither of those numbers are particularly huge for modern GPUs. I'd wager that a compute shader + mesh shader based version of this could hit 2M sprites at 200 fps, though at some point we'd have to argue about what counts as "cheating" - if I do a clustered occlusion query that results in my pipeli…

I've been able to reach 5M particles at 60 fps on a very naive (as a GPU noob) implementation that uses Qt's RHI, which has some unnecessary copying and safeties, with compute + vertex + fragment.
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