iPad 2

[Ailuros]

Better than nothing yes, but not really worth the hussle.

No one enables AF in iPad 2 games because SGX doesn't have AF; place the blame squarely on IMG. Adreno does have it, or at least it did and I assume they didn't drop it. I don't know if anyone else does.

ULP GF/T2 does.

Of course just because we're talking about AA and down-sampling and what have you doesn't mean we don't care about AF, but I have a hard time considering it a more important feature.. AF tends to only effect a small part of the screen and that depends largely on what kind of scene. AA also improves image quality. And MSAA doesn't waste any fill-rate or bandwidth on SGX and similar tilers, mostly just spends depth-fill. I don't know how it compares with AF in terms of die size but it seems like with AF you'd need more if you have it on every TMU (maybe you could separate it so there's just some shared AF unit sitting out there when it's needed - maybe this is how it's done?)

Depends on the scene IMHO entirely. If you should be moving indoors with walls in close range, it might not be worth it. The wider the viewable range in front of the player the more it becomes a necessity.

I don't know if its supported in hw or not on SGX and what the performance penalty could be, yet in my mind if you're going to go for a very high resolution on a relatively small screen estate something like AF takes priority for my taste than MSAA. Ideally of course I'd like to have both, yet if there should be any dilemma I'd be looking for AF first. With a very high ppi polygon edge/intersection aliasing obviously isn't going to get eliminated, but the jaggies still tend to get smaller.

How expensive is it really to implement adaptive AF in TMUs (honest question)?

 

[Rys]

All SGX cores can do AF, although to varying degrees. On DX9-level cores it's up to 16x, adaptive. Enabling it depends on the vendor and the software platform, and at least on some combinations of platform/API that can be problematic for non-technical reasons.

 

[tangey]

the GLview app for iphone/ipad gives some info on the capabilities of the graphics core.

Interestingly it suggests the "bus speed" on an ipad2 is 250Mhz, whether that translates to the speed of the sgx543MP2, i don't know, but the equivalent figure on the iphone4 is 100Mhz, so I think its highly likely.

In relation to AF, the benchmark facility of the above utility has options to set AF to 0,1 or2 (I think the ipad2 has the same settings, I don't have it with me).

Turning on all the options to max (fog,transparency,multisampling,AF) and running the Iron fist scene test on both ipad2 and iphone4 shows the wide difference in performance between the two.

Some combinations of settings give gles1.1 a big speed advantage over 2.0.

 

[ltcommander.data]

All SGX cores can do AF, although to varying degrees. On DX9-level cores it's up to 16x, adaptive. Enabling it depends on the vendor and the software platform, and at least on some combinations of platform/API that can be problematic for non-technical reasons.

Does the SGX543MP2 count as a DX9-level part since I believe it is SGX535 and SGX544MP which are marketed as DX9 compliant parts? Ie. has the Apple A5 actually regressed over the Apple A4 in this area?

Interestingly it suggests the "bus speed" on an ipad2 is 250Mhz, whether that translates to the speed of the sgx543MP2, i don't know, but the equivalent figure on the iphone4 is 100Mhz, so I think its highly likely.

Doesn't the iPhone 3GS also report a bus speed of 100MHz? I thought the SGX535 in the iPhone 4 was felt to be faster than the one in the iPhone 3GS, so if that bus speed is accurate there are presumably multipliers involved. I believe the original iPad also reports a bus speed for 100MHz at least in Geekbench.

 

[Rys]

Does the SGX543MP2 count as a DX9-level part since I believe it is SGX535 and SGX544MP which are marketed as DX9 compliant parts? Ie. has the Apple A5 actually regressed over the Apple A4 in this area?.

543 has a lower maximum level of AF than 535, but that hasn't been a problem on iOS due to the levels exposed.

 

[warmi]

Some combinations of settings give gles1.1 a big speed advantage over 2.0.

Interesting given that GLES 1.x is emulated with 2.0 shaders on iOS devices

 

[Lazy8s]

To the best that I could figure, the SGX parts ending in a zero, one, or three are OpenGL ES 2 focused cores with the potential for basic DirectX 9 compliance, while those ending in a four or five are capable of compliance with at least full DirectX 9 extended (and the 545 with DirectX 10.1, of course.)

Also, 150 MHz for the 3GS's GPU, 200 MHz for the iPhone 4's, and 250 MHz for the iPads 1 and 2's to the best that I could figure.

 

[Ollo]

Doesn't the iPhone 3GS also report a bus speed of 100MHz? I thought the SGX535 in the iPhone 4 was felt to be faster than the one in the iPhone 3GS, so if that bus speed is accurate there are presumably multipliers involved ...

Yes, 100 MHz bus frequecy for 3GS in GLview.

 

[tangey]

MOLLY AND POPPY!

Hmmm.. when did poppy get added in ?

 

[Lazy8s]

The Dreamcast's chip was nicknamed Holly; maybe Molly is a codename for the 16-core Rogue @ 1 GHz (160 Gtex/s effective fill!) that PS4 will obviously be using and Poppy is... uh... something else?

 

[tangey]

The Dreamcast's chip was nicknamed Holly; maybe Molly is a codename for the 16-core Rogue @ 1 GHz (160 Gtex/s effective fill!) that PS4 will obviously be using and Poppy is... uh... something else?

I've been assuming Molly was the PS vita, and Poppy was the PS4....obvious really !

 

[cjo]

Heh, no IMG references there Molly and Poppy are Rys' bundles of cute-evil-furriness.

 

[Squilliam]

Heh, no IMG references there Molly and Poppy are Rys' bundles of cute-evil-furriness.

So all this time they've been kitty cats?

 

[Rys]

Damn you, cjo! I was waiting for them to show up on investor message boards as Rogue codenames

 

[Arun]

Damn you, cjo! I was waiting for them to show up on investor message boards as Rogue codenames

Wait, so you did NOT name your cats after Imaginations codenames? I am deeply disappointed in you!

 

[cjo]

I never mentioned cats or kittens. In other totally unrelated news, Rys absolutely isn't working on a furry cute skynet in his spare time.

 

[Ailuros]

*leaves post blank and points to his signature*

 

[Squilliam]

*ponders signature for a second*

Does threatening cats get us any closer to real information on next generation handheld graphics technology?

 

[Simon F]

Does threatening cats get us any closer to real information on next generation handheld graphics technology?

No. What it might get you is a tetanus injection after having a claw or a canine driven through your finger.