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Xbox Dev Demonstrates NVIDIA GeForce RTX 2080 Ti & Xbox Series X Mesh Shaders Performance With DirectX 12 Ultimate API

Ozriel

Member


STALKER 2 looks great, its just when i saw the faces, its not like it couldnt be done on previous gen. Not down playing this game, it looks great.

these are zoomed out Scenes. Check out that rooftop scene at the end of the trailer
 

Riky

My little VRR pleasure pearl goes vrrrooommm.
That was pure speculation by Alex on resetera. Words left out: "my hunch", "without saying positviely for certain".

"
In 2017, to accommodate developers’ increasing appetite for migrating geometry work to compute shaders, AMD introduced a more programmable geometry pipeline stage in their Vega GPU that ran a new type of shader called a primitive shader. According to AMD corporate fellow Mike Mantor, primitive shaders have “the same access that a compute shader has to coordinate how you bring work into the shader.” Mantor said that primitive shaders would give developers access to all the data they need to effectively process geometry, as well.

Primitive shaders led to task shaders, and that led to mesh shaders."

"
Mesh shaders will expand the capabilities and performance of the geometry pipeline. Mesh shaders incorporate the features of Vertex and Geometry shaders into a single shader stage through batch processing of primitives and vertices data before the rasterizer. The shaders are also capable of amplifying and culling geometry."

"The mesh shader outputs triangles that go to the rasterizer. It’s just a set of threads and it’s up to the developer how they work. With a mesh shader, you program in a group with many threads working together in cooperation rather than locally. When finished, it outputs a small index triangle list. All threads do individual things and vertex data remains unchanged."

Not just Alex, how much difference it will make is unclear though, maybe not much. I think SFS is a far bigger deal.
 

Topher

Gold Member
"
In 2017, to accommodate developers’ increasing appetite for migrating geometry work to compute shaders, AMD introduced a more programmable geometry pipeline stage in their Vega GPU that ran a new type of shader called a primitive shader. According to AMD corporate fellow Mike Mantor, primitive shaders have “the same access that a compute shader has to coordinate how you bring work into the shader.” Mantor said that primitive shaders would give developers access to all the data they need to effectively process geometry, as well.

Primitive shaders led to task shaders, and that led to mesh shaders."

"
Mesh shaders will expand the capabilities and performance of the geometry pipeline. Mesh shaders incorporate the features of Vertex and Geometry shaders into a single shader stage through batch processing of primitives and vertices data before the rasterizer. The shaders are also capable of amplifying and culling geometry."

"The mesh shader outputs triangles that go to the rasterizer. It’s just a set of threads and it’s up to the developer how they work. With a mesh shader, you program in a group with many threads working together in cooperation rather than locally. When finished, it outputs a small index triangle list. All threads do individual things and vertex data remains unchanged."

Not just Alex, how much difference it will make is unclear though, maybe not much. I think SFS is a far bigger deal.

Ok? That talks about mesh shaders generally. What part of that says: "Series X | S has a more complete programmable front end (Mesh Shaders / VRS / SFS) than the old PS5 primitive shaders"?

And here is the link to that information:


It also says:

"Epic developed a mesh shader demo for the PS5 called “Nanite virtualized micropolygon geometry”. It generates 20 million triangles."
 
??? Introduction to Mesh Shaders (OpenGL and Vulkan) | Geeks3D
Mesh Shaders are not a DX12U only feature. DX12U just has it in it so hardware that supports it, can be used.


Your own words: "At least get educated on the matter before speaking."
why didn't you inform yourself before you write such FUD. Primitive Shaders were a concept before they evolved into mesh shaders. That doesn't make a vega GPU capable of executing mesh shaders (other than with some software tricks but really slow).
Yes, you can convert almost anything to be run on older GPUs, as the shaders are more or less mini-processors than can execute many things. But that would be really, really slow.
The differences between some customizations Sony and MS did are, that Sonys customizations already play a role right now. To have advantages from something like Mesh Shaders, the game/engine must be developed with this feature in mind. It is much harder to "just" use it with todays games and get something out of it.
Good lord you guys call anything FUD these days.

Perhaps check your reading comprehension.

I never said Vega was capable of Mesh Shaders, but that the hardware changes nessercy for Mesh and Primitive Shaders has been present in AMD GPU’s since Vega. No AMD white paper has suggest otherwise up to and including RDNA 2.

The rest of what you are saying is just conjecture and my original point still stands.
 

Riky

My little VRR pleasure pearl goes vrrrooommm.
Ok? That talks about mesh shaders generally. What part of that says: "Series X | S has a more complete programmable front end (Mesh Shaders / VRS / SFS) than the old PS5 primitive shaders"?

And here is the link to that information:


It also says:

"Epic developed a mesh shader demo for the PS5 called “Nanite virtualized micropolygon geometry”. It generates 20 million triangles."

It clearly states that Primitive and Mesh Shaders are not identical as one lead to the other, Alex obviously didn't just make up his theory, he's obviously heard it from a developer like everything else they say. Then there is the joint statement at the RDNA2 reveal that says the same thing.
 

Topher

Gold Member
It clearly states that Primitive and Mesh Shaders are not identical as one lead to the other, Alex obviously didn't just make up his theory, he's obviously heard it from a developer like everything else they say. Then there is the joint statement at the RDNA2 reveal that says the same thing.

So what point are you making? That primitive and mesh are not the same thing? Ok? That it?
 
Thanks for taking time to reply. So you think "Full programmatic control" statement of the presentation simply means primitive or mesh shader implemention just like XSX/XSS one, nothing distinctive or beyond that right?

From the die analyses there doesn't seem to be anything substantially different between the PS5 RDNA2 and the PC/XS RDNA2 GPUs other than the ROPs, whereas the PS5 uses the older, less area-efficient but with higher pixel fillrate throughput block from RDNA1 GPUs. That means the shader processors, command processors, geometry processors, etc. are probably all the same.

That said, it doesn't look to me like the PS5's triangle culling accelerators are better than all the other RDNA2 GPUs out there, in the hardware. That said, software APIs can make worlds of difference in how often and effectively these capabilities can be used. It could be that Sony invested more man-months into the API features that let developers use hardware accelerated culling, whereas Microsoft invested more in other areas such as ML reconstruction for example.



??? Introduction to Mesh Shaders (OpenGL and Vulkan) | Geeks3D
Mesh Shaders are not a DX12U only feature. DX12U just has it in it so hardware that supports it, can be used.
The point was API nomenclatures != hardware capability.
OpenGL and Vulkan also share the "Vertex Shader" name, but they don't share the "Pixel Shader" name. It doesn't mean the Fragment Shaders are any worse than the Pixel Shaders if they are both based off the same Shader Model.



I never said Vega was capable of Mesh Shaders, but that the hardware changes nessercy for Mesh and Primitive Shaders has been present in AMD GPU’s since Vega. No AMD white paper has suggest otherwise up to and including RDNA 2.
From AMD's own documentation it looks like the Vega's Primitive Shaders and RDNA2's Primitive / Mesh Shaders have the same capabilities, but for the feature to be usable by devs, they had to increase performance quite a bit.
 

Allandor

Member
Good lord you guys call anything FUD these days.

Perhaps check your reading comprehension.

I never said Vega was capable of Mesh Shaders, but that the hardware changes nessercy for Mesh and Primitive Shaders has been present in AMD GPU’s since Vega. No AMD white paper has suggest otherwise up to and including RDNA 2.

The rest of what you are saying is just conjecture and my original point still stands.
You wrote
"The hardware necessary for Mesh and Primitive Shader support has been present in all AMD GPU’s since Vega"
Which would mean that Vega would already support mesh shaders in hardware, which is just not true.

Yes you can do almost anything with these small processors but to speak of hardware support is imprecise (at least) and really Missleasing.
 
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You wrote
"The hardware necessary for Mesh and Primitive Shader support has been present in all AMD GPU’s since Vega"
Which would mean that Vega would already support mesh shaders in hardware, which is just not true.

Yes you can do almost anything with these small processors but to speak of hardware support is imprecise (at least) and really Missleasing.

So I did a little more digging.

Saying that any GPU in recent years can run Mesh Shaders but just “slower” lacks a lot of context.

AMD’s Vega introduced the hardware changes necessary in the geometry engines to accommodate Mesh/Primitive Shaders. This was by allowing the graphics pipeline to access compute shader functionality.

RDNA 1 then unified the geometry engines from Vega to increase performance for polygon throughput and there’s been zero changes upto and including RDNA 2 (So PS5 and Series X as well).

So yes in theory Vega can run Mesh Shaders at a hardware level and the performance will depend on the compute capabilities of the GPU itself, but API and driver support maybe not.

I recommend going through LevithanGamer2 threads (who specialises in gaming and hardware architecture).



To say Primitive Shaders are inferior to Mesh Shaders is mIsleading, the raw performance gains are the same, to say that PS5 can’t support Mesh Shaders (as posters on here have claimed) is also flat out wrong, the only reason they wouldn’t support is if Sony decided not to add any API support.
 
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