Current state of Snapdragon-based CPUs in PPSSPP

[Henrik]

Good to hear that! Can you tell us which games slow down the most from enabling simulate block transfers?

[stodag]

no doubt its been asked but what is simulate block transfer.. and whet does it do?

[solarmystic]

@stodag

I'd leave the technical explanation to the experts (like Henrik and [Unknown]), but from what I gather, it's a much more robust and lighter replacement for the Read Framebuffer to Memory modes that were used to accurately emulate certain effects/functionality in various games.

Examples include:-

1. Minimap and Save Screenshot functionality in Ys Seven.

2. Photo mode in Soul Calibur.

3. The Sun effects in Burnout Legends.

4. Menu transparency and Save screenshot functionality in Trails in the Sky.

And so on. More importantly, it only activates on a per game basis and will not cause any global performance hit in games that do not require it, unlike the Read Framebuffer to Memory modes which killed performance in every game.

[[Unknown]]

Actually, Danganronpa uses a specific hack now, rather than simulate block transfer.

For a technical, but still simple explanation, block transfers are when a game copies a chunk of memory. It happens that when it wants to show a save picture, or create a minimap, most games make a copy / block transfer. Before, these block transfers were not "connected" to OpenGL - now they are.

So when a game copies from memory that on the PSP contains rendered graphics, this downloads the data from OpenGL and copies it.

"Read framebuffers to memory" downloaded all data for all graphics all the time. Whether the game did a block transfer or not.

It also crashed a lot, because it didn't know how big the framebuffers really were sometimes. The block transfer comes with a very important piece of information: size. This allows the block transfers to be a fairly safe alternative to "read framebuffers to memory" as well.

Even more importantly, "simulate block transfers" *uploads* to OpenGL and also transfers between rendered graphics. We had rudimentary support for this before (for videos), but the new functionality is much better. This fixed effects in games that had simply never worked before regardless of configuration.

However, uploading and downloading from OpenGL does come at a cost. So disabling it will give the best speed. But as long as the game is not actually using it, having it on won't hurt speed at all - and when it is using it, it'll fix graphical effects that would be broken with it off (but I do know of a couple games which do block transfers for no good reason every frame - just in case you might open a menu; so if you never open the menu, these games won't be visually better but will be a bit slower.)

-[Unknown]

[stodag]

ok thx, I did look for the explanation in settings explained but ccouldnt find any so thats why I asked here seeing you was on the subject.. thx again.

[bomberman46]

(06-14-2014 07:16 AM)Henrik Wrote:  Good to hear that! Can you tell us which games slow down the most from enabling simulate block transfers?

Most games seem to make no difference in speed. In fact, I think more games are less 'broken' (for lack of better word) which means compatibility is better.

For example, Photo Kano was practically broken because the photo function didn't work before. I just tried it again and the game crashed now when it was unchecked. Having it checked, the game made the photo function within the game work and get past the story parts that couldn't previously before.

One game that really took a big dive in speed is Fate Extra, but this was with a previous build from the one I'm using now (I believe v0.9.8-1020-g48d4c4c was the previous one). I noticed with it checked, right from the beginning the graphic for the text part have a background now instead of a solid black background. The new build that I'm using (v0.9.8-1164-g6a89658) is back to black background even with it checked and the speed more or less the same whether it's checked or not. So the graphic doesn't work like before, but the speed is improved I guess?

Anyway, I'll test more games since the compatibility is making a quite an improvement these days. Sorry for the long fat message.

[GamerzHell9137]

How are the games working right now on Snapdragons?
I thought to get a phone for normal usage but it would be cool to know if it can run PSP games or not.
LG D320 L70 or LG Optimus L9 II were in my mind cause they were somewhat cheap and looking good for me.

[theENTER]

On my s4 mini(1.7 dual core andreno 305) runs most games 25-30(30 is max for me) fps and speed is 90-100%(=most games are enjoyable thank to the speed) how is s4 quad core and note 3??

[Nyco30]

Hello everyone. This is my first day and message on this forum.
I DLed PPSSPP yesterday (0.9.8) on my brand new 1+1 (Snapdragon 801 / 3Gb RAM), thinking that hell yeah, let's kick some asses with this beast on PSP games. I did not put any build ATM.
Well, the result is quite disappointing, lagging way too much even if I tweak the settings.
Sorry, I'm pure noob when it comes to this. Anyone can tell me what build I should use and how to install it on the device? I DLed this one ppsspp-v0.9.8-1633-g06f058d-android but I'm not sure it is the right one, neither where to put it.

Thanks a million for your help,and kudos to the admins!!!

[EDIT] already read noob guides. Improved the speed indeed, but really not enough. FFVII Crisis Core still at 15-20 FPS with all suggestions made...Can't believe it cannot do more than that.
Tried also to put the last build to work (launch it through my device) but states that another version already exist with another signature...What should I do?

[theENTER]

Thats strange...my phone galaxy s4 mini is far weaker than yours but while playing crisis core, im around 30(thats max for me) thus almost full speed most times....but did you enable fast memory option, change cpu clock speed and other setting of the emulator(pls Dont enable multithread option!! It will cause big problem!)??


somewhere in forum, there is thread that will help you but the forum doesnt allow me to post click able link...sorry

[tiktakt0w]

Enabling Multi threading doesn't necessarily mean that your game will lag (this applies to all of the settings in ppsspp). You must see if a game will perform better with it or not.

[Nyco30]

Maybe with latest build I could make it work? How can I apply latest build on the ppsspp apk? (in relation with my last edit from previous post)
On another note, Dissidia works almost fine. 17 FPS is still playable, but not that enjoyable...

[theENTER]

If i remember correctly, ppsspp has problem on andreno devices with full HD screens like s4 and note 3, but not qHD screen as my s4 mini since it runs almost 100% speed with seldom fps drop(though never tried GoW or Tekken)

thus i guess ppsspp works better on devices with minor screen resolution....for now

[tiktakt0w]

Not really. It's just that the adreno 320/330 has pretty much f***ed up drivers and qualcomm CPU's (specifically snapdragon s4 and up) have poor NEON performance.

[georaldc]

Just got my oneplus (snap801) and did a very quick test with Tekken 6 and so far, the game runs around 10fps faster than my Nvidia Shield. Seeing all the snapdragon complaints, am I supposed to expect even better performance than that? Or are both snapdragon and tegra devices experiencing performance issues?