paraLLEl N64 RDP – Android support and Intel iGPU improvements – What you should know (and what to expect)

Libretro Team
Ridge Racer 64 running on Parallel RDP on an Android phone (with RetroArch)
Ridge Racer 64 running on Parallel RDP on an Android phone (with RetroArch)

Themaister wrote an article a few days ago talking in-depth about all the work that has gone into ParaLLEl RDP since launch.

Two of the important things discussed in this article were:
* Intel iGPU performance
* Android support

What you might not have realized from reading the article is that with the right tweaks, you can already get ParaLLEl RDP to run reasonably well. As indicated in the article he wrote, Themaister will be looking at WSI Vulkan issues specifically related to RetroArch since there definitely do seem to be some issues that have to be resolved. In the meantime, we have to resort to some workarounds. Workarounds or not, they will do the job for now.

How to install and set it up

  • In RetroArch, go to Online Updater.
  • (If you have paraLLEl N64 already installed) – Select ‘Update Installed Cores’. This will update all the cores that you already installed.
  • (If you don’t have paraLLEl N64 installed already) – go to ‘Core Updater’, and select ‘Nintendo – Nintendo 64 (paraLLEl N64)’.
  • Now start up a game with this core.
    Go to the Quick Menu and go to ‘Options’. Scroll down the list until you reach ‘GFX Plugin’. Set this to ‘parallel’. Set ‘RSP plugin’ to ‘parallel’ as well.
  • For the changes to take effect, we now need to restart the core. You can either close the game or quit RetroArch and start the game up again.

Intel iGPU

What you should do for optimum performance right now:

  • For Intel iGPU, I have found that what makes the biggest difference by far (on Windows 10 at least) is to run it in windowed mode instead of fullscreen. Fullscreen mode will have horribly crippled performance by comparison.

Performance

Once you have done this, the performance will actually not be that far behind with a run-off-the-mill iGPU from say a 2080 Ti (in asynchronous mode). Sure, it’s still a bit slower by about ~30fps, but it’s no longer the massive gulf in performance it was before where even Angrylion was beating ParaLLEl RDP in the performance department.

With synchronous, the difference between say a 2080 Ti and an iGPU should be a bit more pronounced.

Hopefully in future RetroArch versions, it will no longer be necessary to have to resort to windowed mode for good performance with Intel iGPUs. For now, this workaround will do.

Android

What you should do for optimum performance right now:

  • Turn vsync off. Go to Settings -> Video -> Synchronization, and make sure that ‘Vertical Sync (Vsync)’ is disabled.

NOTE: It is imperative that you turn V-Sync off for now. If not, performance will be so badly crippled that even Angrylion will be faster by comparison. Fortunately, there will be no noticeable screen tearing even with Vsync disabled right now.

Performance

I tested ParaLLEl RDP on two devices:

  • Nvidia Shield TV (2015)
  • Samsung Galaxy S10 Plus (2019) [European Exynos model]

NOTE: The European model of the Galaxy S10 Plus used here has the Samsung Exynos SoC (System-On-A-Chip). Generally these perform worse than the US models of the Galaxy phones, which use a Qualcomm Snapdragon SoC instead. You should therefore expect significantly better performance on a US model.

Performance on Shield TV

Here are some rough performance figures for the Nvidia Shield TV –

Title Performance
Mortal Kombat Trilogy 87 to 94fps
Yoshi’s Story 99fps
Doom 64 90 to 117fps
Tetris 64 117fps
Starcraft 64 177fps

It’s hard to put an exact number on other games, but just from a solely gameplay-focused perspective, you can get a near-locked framerate with games like Legend of Zelda: Ocarina of Time and Super Mario 64 if you run the PAL versions (which limit the framerate to 50fps instead of 60fps with NTSC versions). There might still be the odd frame drop in certain graphics intensive scenes but nothing too serious.

Similarly, games like 1080 Snowboarding drop below fullspeed with the NTSC version, but running them with the PAL version is nearly a locked framerate in all but the most intensive scenes.

Performance on Samsung Galaxy S10 Plus

Performance on a high-end 2019 phone like the Galaxy S10 Plus can tend to be more variable, probably because of the aggressive dynamic throttling being done on phones. Sometimes performance would be a significant step above the Shield TV where it could run NTSC versions of games like Legend of Zelda: Ocarina of Time and Super Mario 64 at fullspeed with no problem (save for the very odd frame drop here and there in very rare scenes), and then at other times it would perform similarly to a Shield TV. Your mileage may vary there.

Conclusions

Overall, it’s clear that certain battles have to be won on the Vulkan side, especially when it comes down to having to disable vsync at all so far for acceptable performance.

We’d like to learn more from people who have a Samsung Galaxy S20 or a similar high end phone released in 2020. Even a Snapdragon version of the S10 Plus would produce better results than what we see here.

So, Low-Level N64 emulation, is it attainable on Android? Yes, with the proper Vulkan extensions, and provided you have a reasonably modern and fast high end phone. The Shield TV is also a decent mid-range performer considering its age. Far from every game runs at fullspeed yet but the potential is certainly there for this to be a real alternative to HLE based N64 emulation on Android as hardware grows more powerful over the years.

FAQ

Some specific issues should be addressed –

Game compatibility is significantly lower on Android right now

The mupen64plus-core part of ParaLLEl N64 is older than the one found in Mupen64plus next. While on PC this is not so much of an issue because of the generally mature (but slower) Hacktarux dynarec, on ARM platforms it is a different story since new_dynarec was in a premature state back then. Not only that, LLE RDP + RSP plugin compatibility with new_dynarec was not even a consideration back then. So some games might not work at all right now with Parallel RDP+RSP on Android.

ParaLLEl N64 will likely receive a mupen64plus-core update soon, and Mupen64Plus Next might also in the near future get ParaLLEl RDP + ParaLLEl RSP support. So this situation will sort itself out.

You get a display error showing ‘ERR’ on your Android device

The Vulkan driver for your GPU is likely missing these two Vulkan extensions, which ParaLLEl RDP requires.

VK_KHR_8bit_storage
VK_KHR_16bit_storage

(Intel iGPU) Performance is halved (or more) in fullscreen mode

Known issue, read above. These issues have been identified and it’s a matter of finding the appropriate solution for these issues.

Mupen64Plus Next 2.0 – 64DD Support, Angrylion and GlideN64 in one build, Parallel RSP support, and Android!

Libretro Team



What a massive release we have for you today! M4xw has been really delivering the goods now and we’re pleased to release Mupen64plusNext 2.0 today. This release would not be as significant as it is today without the combined efforts of LuigiBlood, Gillou, Fzurita and Themaister.

The latest version is now available on Android, Linux, Windows, and Libnx (Switch)! Updating to the latest core is as easy as starting RetroArch, going to Online Updater, and selecting ‘Update Installed Cores’. If you have not installed the core yet, instead go to Online Updater and select ‘Mupen64 Plus Next’ or ‘Mupen64 Plus Next GLES3’ from the list.

64DD support


Previously, only Parallel N64 had 64 Disk Drive support, courtesy of LuigiBlood. Work on it was left rather incomplete though.

Mupen64Plus Next now has a new implementation that LuigiBlood feels more comfortable with. Currently the way that you load 64DD content with Mupen64 Plus Next is completely different from how you do it on Parallel N64.

First, you need a BIOS file. Make sure the file ‘IPL.n64’ is located in your /Mupen64plus directory.

You can either use the subsystem for 64DD, or you can name the disk image the same as the ROM including extension.

If you need to load a specific cart with the Disk image, that would be: “homebrew.n64” and “homebrew.n64.ndd” then Load Content “homebrew.n64”.

Zelda 64: Dawn & Dusk - unofficial 64DD expansion game to OOT
Zelda 64: Dawn & Dusk – unofficial 64DD expansion game to OOT
64DD had an exclusive Sim City version, called Sim City 64
64DD had an exclusive Sim City version, called Sim City 64

Angrylion and GlideN64 in same build!

Previously, Mupen64Plus Next only had GLiden64 as an RDP graphics option, and only ParaLLel N64 had Angrylion.

Now, Mupen64Plus Next has both, and allows you to choose between them. To do so, go to Quick Menu -> Options, and change RDP Mode. Angrylion is a low-level software-rendered accurate renderer, while Gliden64 is a high-level emulation OpenGL renderer.

Angrylion is the most accurate the graphics are going to get with an N64 emulator – and it can be made relatively fast now thanks to the multithreading capabilities of Angrylion RDP Plus, as well as the Parallel RSP dynarec. You cannot internally change the resolution with Angrylion beyond what the N64 was capable of.

Gliden64 on the other hand takes a more pragmatic approach and emulates the RDP with a high-level approach. It is an OpenGL renderer. You can upscale the graphics, and there is a wide array of settings to tweak.

Most regular people will probably be satisfied by Gliden64 and HLE RSP, and indeed, for many platforms, that might be the only feasible way of attaining fullspeed. But Angrylion definitely fulfills a niche for those that want a more accurate portrayal of N64 graphics – and combined with an upscaling shader, it can still look remarkably good.

Parallel RSP support

Parallel RSP saw its first debut in ParaLLel N64, and now we have it backported to Mupen64Plus Next as well! Read our articles here and here for more information on Parallel RSP.

Parallel RSP is a Low-Level RSP plugin that serves as a replacement for Cxd4. You can use it in combination with Gliden64 and/or Angrylion. With Angrylion you are pretty much required to use either Parallel RSP or Cxd4 as your RSP plugin, HLE RSP won’t work. Cxd4 is an interpreter RSP plugin while Parallel RSP is a dynarec RSP plugin. Parallel RSP should be noticeably faster across the board than Cxd4.

You might see better performance with Mupen64plus Next and Angrylion/Parallel RSP vs. ParaLLEl N4, because Mupen64Plus Next uses the New_dynarec CPU core. ParaLLEl N64 instead uses the Hacktarux dynarec CPU core, which can be a tad bit slower.

NOTE: You can also use Parallel RSP in combination with Gliden64. While HLE RSP has made significant strides in emulating the vast majority of known RSP microcodes, there might still be some microcodes that have either not been reversed at all or were not accurately reversed. In this case, an LLE RSP plugin is always an option, and Parallel RSP ought to be the faster one of the two options.

Angrylion + Parallel RSP on Android – approaching fullspeed on high end phones?

50fps with Super Mario 64 on a Galaxy S10+ - RetroArch Mupen64Plus - Angrylion - Parallel RSP
50fps with Super Mario 64 on a Galaxy S10+ – RetroArch Mupen64Plus – Angrylion – Parallel RSP

Angrylion is now available as an option for both Parallel N64 and Mupen64plus Next on Android.

Mupen64plus Next definitely has a performance advantage over Parallel N64 when it comes to Angrylion. Tests have shown that the first area in Mario 64 gets about 50-51fps on a Samsung Galaxy S10+ American Snapdragon version and 40/45fps on a Samsung Galaxy S10+ European Exynos version.

Will the next generation of phones be capable of pulling off Angrylion at fullspeed? It’s certainly a tantalizing prospect!

NOTE: There might be several ways you have to ‘nudge’ your Android device to get the best performance out of Angrylion/Parallel RSP. Some things you can try:

– Enable ‘Sustained Performance Mode’. If you find it helps with the framerate, leave it on. If not, disable it.
– Enable ‘Disable Expansion Pak’. It might result in a small performance boost for games that don’t support the Expansion Pak.
– Go to Quick Menu -> Options. VI Overlay can have an additional performance impact on the framerate. ‘Filtered’ is the most demanding option while ‘Unfiltered’ should be fastest.
– Go to Quick Menu -> Options. ‘(AL) Multi threading)’ is set to ‘all threads’ by default, but in case for whatever reason the software does not make the right core determination, you might want to set the amount of cores manually here. Base this number on the amount of CPU cores that your Android device has.

Angrylion + Cxd4
Performance results – LG G8X and Samsung Galaxy S10+ (Snapdragon)

Angrylion + Parallel RSP
Performance results – LG G8X and Samsung Galaxy S10+ (Snapdragon)

HLE RSP improvements – HVQM support

The HVQM RSP microcode has now been implemented for HLE RSP (thanks to the combined efforts of CrashOveride and Gillou). In the past, the FMVs for Pokemon Puzzle League would only show up if you used Angrylion and an LLE RSP plugin. Now the graphics glitches in Pokemon Puzzle League and Yakouchuu II should be gone! This means that you can now use the GlideN64 renderer for these games as well.

Difference between ParaLLel N64 and Mupen64Plus Next

Available plugins Mupen64Plus Next: Gliden64, Angrylion

Available plugins Parallel N64: Glide64, Parallel RDP, Rice, GLN64, Angrylion

In Mupen64Plus Next’s favor – it is based on a much more recent mupen64plus-core version than Parallel N64, and thus has benefited from years of fixes and architectural improvements. It also uses the New_dynarec CPU core on Windows/Linux/Mac. It is a bit faster than the Hacktarux dynarec from Parallel N64.

There are also currently some disadvantages. The sound is currently crackly with some games like Doom 64 and Quake 64. There are currently some experiments being explored to deal with these issues.

64DD support right now is implemented completely differently in both cores.

Changelog

  • 64DD support (works through the subsystem menu)
  • Angrylion and GlideN64 are now inside the same build – you can switch inbetween them
  • HLE and LLE RSP support – with LLE your choices are between cxd4 [Interpreter] and Parallel RSP [Lightning/Lightrec dynarec]
  • Parallel RSP support for the first time in Mupen64 Plus Next
  • Available on Android with all of the above!
  • The latest HLE RSP improvements – HVQM support – Pokemon Puzzle League FMV support works now with HLE RDP renderers like GlideN64
  • Mitigation for SPECIAL_INT on downcounter flip – fixes freezes in Legend of Zelda: Majora’s Mask
  • Killer Instinct Gold now works with Angrylion + LLE RSP