Does the PS4 gpu feature PRT?

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The gpu for 7790 and 7970 feature PRT. The Xbox One gpu has it. But does the PS4 gpu feature PRT?
 
The gpu for 7790 and 7970 feature PRT. The Xbox One gpu has it. But does the PS4 gpu feature PRT?



1. Does the PS4 expose the PRT nicely to devs in the form of specific API's or does the devs need to go to the HW to actually be able to use it.

2. Is the PS4s overall design optimized to deliver on PRT, its one thing having a GPU that supports PRT BUT another to have the latency/bandwidth etc across the entire system that can deliver a great PRT experience

XB1 clearly from \\build\ conference is optimized to deliver a great PRT experience for DEVS (api) and for end users (a system whos silicon is designed to deliver a great PRT experience)

ps. I am yet to see ANY good examples on PS4 that leverage PRT in any shape or form!
 
If Xbox One benefits disproportionately from PRT, it's only because it's so hamstrung by its memory architecture in the first place. There's no reason to doubt PRT is exposed in LibGCM. OpenGL has had a PRT extension far longer than DirectX, too, so I wouldn't be surprised if it's there in PSGL.

As for examples, I'm not sure what you expect. The benefits for PS4 will simply be bandwidth savings because the GPU won't be doing unneeded texture reads, reading only the parts actually being drawn.

The idea of design being "specifically optimized for PRT" is, frankly, an absurd idea to begin with. Even in Microsoft's own tech demos they had to contrive a weird constrained memory environment to show it off. The benefits are more about the game production side making it easier to implement things like megatextures with a ton of unique art.
 
...bandwidth savings because the GPU won't be doing unneeded texture reads, reading only the parts actually being drawn.
PRT, or virtual texturing in general, doesn't save any memory bandwidth. The GPU only accesses the memory areas (cache lines) that are sampled in the pixel shader. The extra data that might be (or not be) in memory isn't touched at all.

The main purpose of virtual texturing is to save memory. With it you can keep textures partially in memory (fine grained spatial and LOD locality), streaming only texels that are needed to render the current frame from HDD to memory. It can also be used to save processing cycles, for example by caching results of complex decaling or procedural texturing systems (process only the surface areas that are needed, and reuse the results for several frames).
 
PRT, or virtual texturing in general, doesn't save any memory bandwidth. The GPU only accesses the memory areas (cache lines) that are sampled in the pixel shader. The extra data that might be (or not be) in memory isn't touched at all.

The main purpose of virtual texturing is to save memory. With it you can keep textures partially in memory (fine grained spatial and LOD locality), streaming only texels that are needed to render the current frame from HDD to memory. It can also be used to save processing cycles, for example by caching results of complex decaling or procedural texturing systems (process only the surface areas that are needed, and reuse the results for several frames).

Hmm, that would also help with load times, from the other thread.
 
Folks need to STOP reusing these damn initialisms! I get halfway through this thread wondering what kind of idiotic thread this is talking about Pre-computed Radiance Transfer as some sort of "bullet-point" feature before I realize you're talking about virtual texturing... :devilish:
 
Folks need to STOP reusing these damn initialisms! I get halfway through this thread wondering what kind of idiotic thread this is talking about Pre-computed Radiance Transfer as some sort of "bullet-point" feature before I realize you're talking about virtual texturing... :devilish:

To be fair, I think the question was whether the PS4 GPU has hardware-level implementation of virtual texturing, and AMD calls that feature Partially-Resident Textures. If they were just discussing in the general sense, then I think virtual texturing should be used instead.
 
To be fair, I think the question was whether the PS4 GPU has hardware-level implementation of virtual texturing, and AMD calls that feature Partially-Resident Textures. If they were just discussing in the general sense, then I think virtual texturing should be used instead.

Then the answer is yes it is a part of GCN architecture, and will be exposed in the API.
 
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