WatermelonDS 0.8.0.rc2: Vulkan, Audio and Library Stability Update!

[SapphireRhodonite]

WatermelonDS 0.8.0.rc2 is here!!!

This release focuses on smoother high-resolution Vulkan performance, audio and graphics fixes reported by the community, and quality-of-life improvements for libraries, saves, and RetroAchievements.

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Vulkan performance improvements

Vulkan has received major performance and stability improvements in this release.

Repeated calculations and redundant reads were reduced, and rendering work is now grouped more efficiently. These improvements benefit different internal resolutions and are not exclusive to a single chipset or device family.

Tested results include:

Device / SoC	Internal Resolution	Result in tested sections
T820	6x	Close to 60 FPS in the tested sections of Spirit Tracks, Phantom Hourglass, and Dragon Ball Origins. Smoothness was also confirmed in user testing.
Snapdragon 865	8x	Close to 60 FPS. Spirit Tracks and the reviewed sections of Golden Sun now hold pacing better, with both technical and user validation.
Snapdragon 8 Gen 2	16x	Close to 60 FPS in the measured Spirit Tracks section, without DRS or frameskip.

These results depend on the game, scene, device, driver, and configuration. They are not a guarantee of 60 FPS across the full catalog.

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Game-specific Vulkan improvements

• Spirit Tracks and Golden Sun: reduced stutter in demanding tested scenes.
• Golden Sun: reduced waiting during startup and battles.
• Pokémon Black 2: smoother performance in heavy tested scenes.
• Pokémon Black 2: fixed a memory growth issue that could eventually close the game.
• Vulkan startup: graphical preparation is reused between sessions.
• Vulkan startup: loading is now shown while graphics are prepared, avoiding long black-screen waits after loading a ROM.
• Custom drivers: reduced stalls that were slowing performance with Turnip on tested devices.
• Graphics fidelity: improved dual-screen composition, fog effects, transparency, and scenes that combine 2D and 3D elements at high resolution.

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New options and usability improvements

DRS, Dynamic Internal Resolution

Vulkan now includes optional DRS, or dynamic internal resolution.

When enabled, Vulkan can temporarily lower the internal resolution in demanding scenes and raise it again when there is enough headroom, prioritizing smoother gameplay.

DRS is optional and disabled by default.

Vulkan frameskip

Vulkan now supports frameskip modes:

• Off
• Manual
• Auto

Frameskip allows the emulator to draw fewer frames when needed to help maintain game speed.

If DRS is enabled, frameskip is disabled. You choose one strategy or the other.

New internal resolutions

New internal resolution options are available:

• 12x
• 16x

These are available in both global settings and per-game settings.

On capable devices, this can reach up to 4096×3072 per DS screen.

Visible resolution indicator

• A new optional visible resolution indicator can show the internal resolution currently being used compared to the configured one.

Mute during fast-forward

• A new option allows audio to be muted while using fast-forward.

NDZ ROM support

• WatermelonDS can now open compatible ndz-studio ROM files from the library without extracting them manually.
• Older or unsupported variants now show the reason why they cannot be opened.

Custom driver controls

• Custom driver controls now only appear when an Adreno GPU is identified.
• Other GPUs continue using the system Vulkan driver.

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Fixed: audio and RetroAchievements

Source	Fixed issue
#142	Periodic RetroAchievements communication no longer causes the brief hitch that stopped emulation.
Sonic Rush and Spirit Tracks	Fixed audio slowdown and pitch changes in the reported scenarios.
Pokémon Black 2	Fixed in Black 2. Audio no longer accumulates delay when increasing internal resolution in the tested case.
scrcpy and DualCPY	Fixed crackling and audio cuts while capturing or streaming audio in the reproduced path.
Internal testing	Audio returns when increasing volume from zero, without needing to re-enter settings.
Internal testing	Large sets such as Black 2 with 419 achievements can now load. Oversized response failures now show an explanation.
#201	The missable achievements filter now recognizes both modern and legacy types when updating game data.

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Fixed: graphics

Game	What changed
Rhythm Paradise / Rhythm Heaven	Restored the initial screen text and fixed hand and texture corruption when reaching the minigame through normal gameplay, without needing to reload a savestate.
Golden Sun: Dark Dawn	The sun now blends correctly with the background during the moving scene, without the black box.
Sonic Rush	Fixed the reproduced image vibration when accelerating and going through the ramp.
Super Princess Peach	Objects and blocks that Vulkan omitted are visible again.
Pokémon Black 2	Fixed the flash when entering and leaving buildings, and fixed the memory growth that could eventually close the game.
Spirit Tracks	Selector text and cursor are no longer hidden behind other elements.
Vulkan at native resolution	Fixed black screens and crossed content between screens in the identified cases.
Startup with custom driver	Fixed the crash attributed to startup with Turnip.

Additionally, Phantom Hourglass now has Link and Navi shadows restored in Vulkan.

This fixes that part of GitHub #94. The full issue remains open because it contains other cases.

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Fixed: library and saves

Source	BUG
GitHub #206 / Rewind	Larger thumbnails now show both full screens and use the available space better when selecting the moment to rewind to.
GitHub #128 / Per-game icons	Each game can now use the native icon, the RetroAchievements icon, or inherit the global setting.
GitHub #186 / Relaunching	Opening the same already-running ROM from a frontend now resumes gameplay without asking to reload it.
GitHub #173 / Box art	Regional box art is prioritized when the full ROM name matches the catalog.
GitHub #209 / Save import	Importing your own save through another path no longer empties the file.
ROMs with matching names	The selected game opens correctly even if another ROM has the same name and size.
Patreon and Discord	Scanning is much faster for libraries with thousands of games. Recoverable information is preserved, and per-game options are saved correctly with save directories based on file path.
Patreon	Files compatible with the available memory now load. Files that exceed memory limits show a reason. Removing them no longer leaves ghost entries.

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What to test

Please test and report feedback about:

• Vulkan performance at high internal resolutions
• DRS behavior
• Vulkan frameskip behavior
• 12x and 16x internal resolution options
• Audio stability
• RetroAchievements hitching or synchronization issues
• Large achievement sets
• Phantom Hourglass shadows in Vulkan
• Native-resolution Vulkan behavior
• Custom drivers on Adreno devices
• ROM scanning on large libraries
• Save importing
• 7z loading and removal
• Frontend relaunch behavior

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Reporting issues

When reporting issues, please include:

• Device model
• Android version
• GPU if known
• Game title
• Renderer used
• Internal resolution used
• Whether DRS was enabled
• Whether frameskip was enabled
• Whether shaders were enabled
• Whether RetroAchievements was enabled
• Whether a custom driver was used
• Steps to reproduce the issue
• Screenshots or video, if possible
• Logs, if available

Special Thanks

A special thank you to the people who helped test and improve this release:

• Devin on Discord for testing RetroAchievements over long play sessions and helping confirm that the periodic RA hitch was fixed.
• Yumi on Discord for testing audio capture software and helping confirm that captured and streamed audio behaves correctly.
• Jow on Discord for helping improve the audio system. You can find Jow on GitHub here: jojodogm-ctrl

Thank you for taking the time to test, report, and help validate these fixes.

Thank you for testing and supporting WatermelonDS.

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This discussion was created from the release WatermelonDS 0.8.0.rc2: Vulkan, Audio and Library Stability Update!.

[SapphireRhodonite]

Hope you guys like this update!

[OddAnpan]

Unfortunately YuGiOh World Championship 2007 hast now grafical glitches since this update

[SapphireRhodonite]

Unfortunately YuGiOh World Championship 2007 hast now grafical glitches since this update

can you share me your save file/ savestate and wich version is?, to fix it!

[OddAnpan]

How can I send you the Savegame?
This problems happen with vulkan. When I switch to OpenGL, it goes away. But Id like to use vulkan

[SapphireRhodonite]

You can attach it here!, please!

[OddAnpan]

Yu-Gi-Oh! - World Championship 2007 (Europe) (En,Ja,Fr,De,Es,It).sav.zip

[OddAnpan]

The problem is in every game against any opponent. Renderer is vulkan, resolution 6x. Turnip T30. App version is the latest. Before everything was allright. The latest version broke the game for me

[SapphireRhodonite]

Thanks! I will fix this for the next release (rc3), which already fixes a lot of rendering bugs.

[SapphireRhodonite]

have tried one battle but no luck on what is wrong, can you help me uploading a screenshot of bug in vulkan and how it should look on opengl please!

[OddAnpan]

I tried uploading the file but 10 MB is to small. The problem happens If you attack the enemy. Then the cards disappear

[SapphireRhodonite]

Fixed for rc3!

[Nycepter]

On heart gold I am still getting extreme stuttering on vulkan, so far specifically when moving up and down inside houses. Open Gl is fine but has the black lines. Standard driver and no shader, have tried multiple resolutions with the standard being 4, tried signing out of retroachievements, disabling frameskip, enabling dynamic resolution. AYN thor.

[SapphireRhodonite]

Thanks!!, this si the issues that normally I dont catch because there are a lot of games and things to test, really thanks, next release will be preatty soon with all thes fixes!

[Nycepter]

Awesome! I will try to report any others that I may find, I dont play many DS games but want to now that I have my Thor lol. The app is great to use and other than that one thing so far is awesome, you are doing phenomenal work! :D

[lim2222]

All of my roms fail to load,it say all my roms was corrupted,i am sure they're good because they all run by others DS emulator.

[lim2222]

don't bother, fixed by clearing app cache.

[carlosmsalado]

Cross-reference for this RC: issue #220 — auto-load of savestates never works in 0.8.0.rc2

Not a duplicate report, just a pointer, since it is reproducible on the same class of device and the fix looks like a single constant.

→ #220 — Auto-load state is always rejected in 0.8.0.rc2: wrapper validates with SAVESTATE_MINOR = 0 while the pinned core writes minor 1

Short version:

• The core pinned by both rc2 and Develop (melonDS-android-lib@8111a2dd) writes savestates with MAJOR 13 / MINOR 1 (src/Savestate.h:27-28), and its own loader accepts minor <= 1.
• The wrapper, EmulatorViewModel.kt on Develop (checked today), still defines SAVESTATE_MINOR = 0 (line 228); isSavestateHeaderValid() (2394) requires minor <= SAVESTATE_MINOR (2419-2420) and is reached from the quick-slot auto-load path (2371).
• Net effect: the state the build itself has just written is always rejected by its own auto-load guard → "Auto-load state is invalid and was skipped", and the game boots from scratch. Manual load of the very same .ml0 from the pause menu works, so the file is fine.
• 12-byte headers read from the device: rc2 state 4d 45 4c 4e 0d 00 01 00 88 84 2d 01 (minor 1, length = exact file size) vs a 0.7.0 control 4d 45 4c 4e 0d 00 00 00 78 84 2d 01 (minor 0, accepted by the same guard).
• Device: AYN Thor (AYN_Thor), Android 13, 0.8.0.rc2 / versionCode 40, Adreno 740, standard driver, shaders off, RetroAchievements on; auto_save_state_on_exit=true + auto_load_state_on_launch=true.
• Nothing of yours is at risk here: .sav saves are written normally — only the resume point is lost.

Happy to repost the full detail in this thread if Discussions is the preferred triage channel for the RC.

[SapphireRhodonite]

Fixed for rc3

[HJMBgit84]

Super Mario 64 DS Graphic issues video attached

Adreno 650 with custom driver and native driver Snapdragon 865 on Vulkan.

Mario.DS.64-20260928-175102-1790639432968.mp4

[SapphireRhodonite]

Fixed for rc3!

[zoukai333]

Device model:iQOO Neo11 (Snapdragon 8 Elite, Adreno 830)
Android version:
Android 16 (SDK 36)

Problem:
When playing Pokemon Black 2 / White 2 (NDS ROM, Chinese translation), large solid-color blocks appear on the screen, replacing water surfaces, ground textures, or overlapping geometry. The size and position of the solid-color blocks perfectly match the affected water/ground areas.

Steps to reproduce (if applicable):

Launch Pokemon Black 2 / White 2.
Use the Vulkan renderer.
Walk to areas with complex depth layers, such as water surfaces near Virbank Complex or areas where the player character is occluded by buildings/bridges.
The solid-color blocks appear.
Additional troubleshooting details:

In Vulkan mode, this issue occurs regardless of the internal resolution multiplier.
Importing a custom driver (Turnip_Gen8_V37.zip from StevenMXZ) alleviates the issue but does not completely eliminate it.
There is no such issue in OpenGL mode, but the performance is extremely poor.
I have only tested this on my iQOO Neo11.
Before changing the driver:
Image Image - After changing the driver (Turnip driver alleviates the issue): Image Image - After setting the internal resolution to native (the issue still occurs): Image Note:*I do not speak English; this report is presented via AI translation.

[SapphireRhodonite]

can you sent me a savefile please or two where the error is present please!

[zoukai333]

water2_2.zip
Of course, here is a save file from when I returned to Virbank Complex, along with some log files. I'm not entirely sure if they are useful, but hopefully they can help.

During this time, I have been playing the game using melonDS-Android v2.0.1 in OpenGL mode. I found that the errors are far more extensive than just the color blocks, including but not limited to: Pokémon texture errors, rendering errors in certain areas, and failed rendering when receiving medals or using Fly.

Notably, none of these issues occur when I play using melonDS-Android v2.0.1 in OpenGL mode (though performance is poor). I will also try my best to send you screenshots of these errors.
v37_Turnip_v26.3.0-R6.zip
v37_Turnip_Gen8_V37_patch.zip
v37_Turnip_Gen8_V37.zip
Also, here are the custom drivers I have tried.

I tried different versions from the EmuHub app, including Turnip_Gen8_V37.zip, Turnip_Gen8_V37_patch.zip, and Turnip_v26.3.0-R6.zip. Using the custom driver alleviated the color block issue to some extent, but did not completely eliminate it. I hope these files can help you identify if this is a driver compatibility issue.

[SapphireRhodonite]

Fixed for rc3!

[Mrbombastichunk]

Hola amigos, me encanto esta actualización, soy nuevo en esta comunidad así que hay demasidas cosas que desconozco pero como pidieron que probaremos vulkan a mi me paso esto. Cuando la aplicación rota de vertical a horizontal, el renderizado Vulkan a veces no actualiza correctamente el tamaño del búfer de la pantalla (framebuffer swapchain), provocando que la imagen 3D o 2D se estire o se deforme como si siguiera en resolución vertical esto no sucede en render por Software ni en OpenGL mi teléfono es un Realme 11 pro+ 5g
Estas son sus especificaciones
• Pantalla: AMOLED curva de 6.7 pulgadas con resolución FHD+ (2412 x 1080 píxeles), tasa de refresco de 120 Hz, muestreo táctil de 360 Hz y brillo pico de 950 nits.

• Procesador (SoC): MediaTek Dimensity 7050 (6 nm) de 8 núcleos hasta 2.6 GHz con GPU Mali-G68.

• Memoria RAM: 8 GB o 12 GB (con opción de RAM dinámica virtual).

• Almacenamiento interno: 256 GB o 512 GB (no ampliable por microSD).

La solución que encontre fue poner el teléfono en horizontal antes de iniciar el juego 😅 😁

Record_2026-10-10-08-37-32_10eda5aaefef6c2543c2f269885755e1.3.mp4

[SapphireRhodonite]

Fixed for rc3!