longdi
Banned
I've stressed this point forever. Mark Cerny, from the moment he became more publicly prominent amongst playstation gamers and gamers in general, has always shared a wealth of information about any and every major Playstation hardware feature, right down to the ACEs and important communication lanes inside PS4 if he found it important. It's improbable to think the PS5 would possess such major headline next-gen graphics features in its GPU, yet get zero mention from its lead architect.
The SONY MADE THEIR OWN EVERYTHING stuff is ridiculous. We know what Sony made themselves, Mark Cerny told us. He said it was Sony's idea to implement the GPU cache scrubbers and if we saw it in a future GPU then that would be a sign that their collaboration with AMD proved useful for the PC space also, they built their own custom SSD/flash controller and I/O complex with additional task specific hardware inside and their custom hardware decompression unit.
When it comes to GPU features, Mark Cerny actually prepares people watching his deep dive by stressing that new features cost transistors, and they wanted to strike a balance between adding new features while ensuring that developers would not be forced to use those new features, to keep things optional.
One of the first things Mark Cerny stresses that's an advantage of the Geometry Engine is as follows
abort processing of a vertex if all geometry that uses it is off-screen.
Brings handling of triangles and other primitives under full programmatic control
remove back faced or off-screen vertices and triangles,
More complex usage involving primitive shaders allows synthesizing geometry on the fly as it's being rendered
smoothly varying level of detail, addition of procedural detail to close up objects and improvements to particle effects and other visual special effects
Check page six of the Vega Whitepaper as it brings up the next gen geometry engine.
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Important, I am not saying the PS5 has the exact same geometry performance as Vega, because even in the RDNA whitepaper it makes clear that changes were made that significantly improves the geometry performance of RDNA, which means the Geometry Engine from PS5 will not perform the exact same way it does in Vega. In RDNA 1st gen, for example, the cull rate for triangles was more than doubled over Vega.
Features can, and often, undergo improvements or enhancements, which I'm positive are present in PS5, so ignore the more than 17 primitives per clock Vega number as it's sure to be notably larger on PS5, but the core geometry engine primitive shaders functionality that was finally fixed for RDNA 1st gen (it didn't work in Vega) is highly likely one and the same in PS5 with the benefit of obvious benefit of additional architectural enhancements that come with the PS5.
What Mark Cerny described the PS5's geometry engine to be capable of is more or less all present and accounted for in the AMD Vega whitepaper description of the Geometry Engine and primitive shaders. Just because it's a feature first introduced (though never used) for Vega shouldn't be taken as me having a go at the PS5. That doesn't make it "OLD" by any stroke of the imagination. No console or PC title that I'm aware of has ever utilized primitive shaders. And obviously I know of none that utilize the seemingly more advanced Mesh Shaders, which carries the potential to completely replace the fixed function tesselation unit in GPUs.
Nice sussing. Makes sense when you add in MS take on waiting for rDNA2 feature sets.
ps5 primitive shaders and foveated rendering would work well enough in the hands of direct manual access.
But it seems like mesh shaders and vrs are revisions to make things better/easier for developers.