embarrassed-shina-linux-proton

Embarrassed Shina-chan: Linux / Proton fix pack

Makes Embarrassed Shina-chan~ the Naked Wandering College Girl (Steam AppID 2326780, built with RPG Developer Bakin) run on Linux under Proton. Out of the box the game reaches a grey/white screen and then freezes. Even once it boots, the character sprites and all 2D menus are invisible. This pack applies a set of small, documented, reversible fixes to your own copy so the game boots, loads the full 3D map, and renders the characters, menus and UI.

The bugs are in this older Bakin engine build (kmyCore.dll ~5.4 MB, v1.1.0). Newer Bakin games run on the same Proton with no changes at all, since the engine fixed these issues upstream. This pack backports that behaviour into the older build.

What it does not do

It ships no game files: no kmyCore.dll, no bakinplayer.exe, no shaders. It only carries scripts and source that transform your installed copy, and it verifies the original bytes and hashes before touching anything. Every change is backed up and can be reverted with uninstall.sh.

Requirements

• A Linux Steam install of the game, run through Proton (tested on Proton Experimental / 11).
• gcc, patch, python3, od/dd (standard on any desktop Linux).
• The .NET SDK (dotnet), only to build the ~30-line IL patcher for fix 2. The first build fetches Mono.Cecil from NuGet, so it needs network access once.

Install

git clone <this-repo> && cd shina-linux-patch
./install.sh            # auto-detects the game, or pass its folder explicitly

Clone to a path without spaces or : (e.g. ~/shina-linux-patch). LD_PRELOAD cannot handle such paths and the installer refuses them.

Then, as the installer prints:

1. Steam -> the game -> Properties -> Launch Options:

   "/abs/path/to/launcher.installed.sh" %command%
   

2. Wayland only (keyboard focus): close the game fully, then

   bash patches/05-wayland-keyboard.sh "/path/to/.../Embarrassed Shina-chan~ ..."
   

Launch from Steam. Revert anytime: ./uninstall.sh "/path/to/...game folder".

The fixes

#	Symptom	Root cause	What the fix does	Layer
1	Grey screen, no models	scanPlugin reads the in-memory data.rbpack FS, which contains no .dlp asset loaders	1-byte retarget of one call so it uses the on-disk FS creator	kmyCore.dll (native)
2	(same) no .dlp found	Entry.initialize("", null) makes the native path derivation fail under Wine	IL rewrite: pass AppDomain.CurrentDomain.BaseDirectory instead of null	bakinplayer.exe (managed)
3	White screen, "Vertex Attribute Problem", freeze	Mesa cross-stage DCE marks vin_* vertex inputs inactive, so glGetAttribLocation returns -1	keep-alive term in the shader that references every input, scaled by a uniform Mesa can't fold to 0	game GLSL (text)
4a	Characters, menus and all 2D UI invisible	The engine sets up 2D-sprite/UI vertex attributes on the default VAO (0). Legal in an OpenGL compatibility profile, but Wine gives it a core profile where glVertexAttribPointer then fails with GL_INVALID_OPERATION and the driver rejects every default-VAO draw	LD_PRELOAD binds a real VAO whenever the game would use VAO 0	host GL (preload)
4b	Freeze right after the map loads	WASAPI init fails (SndError 923); a thread waits forever on an "audio ready" event	LD_PRELOAD caps INFINITE NtWaitForSingleObject at 10 s	Wine/ntdll (preload)
5	Mouse works, keyboard doesn't (Wayland)	Window uses ICCCM "Globally Active" input model; compositor withholds keyboard focus	Wine registry UseTakeFocus=N (passive model)	Wine registry

Fixes 4a and 4b, plus the IBL BRDF LUT lighting texture, live in one small LD_PRELOAD hook: patches/04-runtime-hook/bakin_minimal.c. Fix 4a is the one that makes the characters and menus appear.

Full technical write-up: docs/TECHNICAL.md.

How to review it

Everything is source or plain text:

• Fix 1, patches/01-kmycore-diskfs.sh: verifies the full 5-byte call instruction (e8 58 92 fd ff) plus a hash check, then changes one byte (0x58 to 0xB8).
• Fix 2, patches/02-pluginpath/Program.cs: the Mono.Cecil IL rewrite, ~30 lines.
• Fix 3, patches/03-shader-vin-keepalive.patch: a unified diff of the shader include.
• Fixes 4a/4b, patches/04-runtime-hook/bakin_minimal.c: the VAO fix is ensure_vao() plus the glVertexAttribPointer / glEnableVertexAttribArray / glBindVertexArray wrappers; the audio fix is the NtWaitForSingleObject splice; plus the IBL LUT drop.
• Fix 5, patches/05-wayland-keyboard.sh: a single registry value.

How the VAO bug was found

Every observable GL state on the character's draw was identical to the visible 3D models: same program, framebuffer, thread, depth/blend/stencil/cull, viewport, even the attached textures. Still, nothing rendered. The break was found by calling glGetError immediately after the character's draw (it returned GL_INVALID_OPERATION) and then installing a glDebugMessageCallback, which reported the exact reason: glVertexAttribPointer(no array object bound). When a draw is invisible despite matching a visible one in every state you can read, the draw itself may be getting rejected; check glGetError on that draw and turn on GL debug output.

Known limitations

A few street props (bus, Traffic light, Swing_ch1, ParkClock_ch1, ...) log a non-fatal "Vertex Attribute Problem" during map load and may show wrong or missing texture mapping. The game runs at full speed and everything else, including characters and UI, renders fine.

Applying this to other Bakin games

Some of these fixes carry over to other games built on the same old Bakin engine (the OpenGL build, kmyCore.dll around 5.4 MB). Others are tied to this one game's files.

Newer Bakin games don't need any of this. They ship kmyDX12.dll and render with DirectX 12 through vkd3d, which avoids the OpenGL bugs. The game 貢げ！女神様, on a newer build, runs on Proton with no patches at all.

What carries over unchanged:

• The VAO fix, which is the main one. It's a plain LD_PRELOAD hook that binds a real VAO whenever the game uses the default VAO 0, and it never references this game. Load it into any old-Bakin OpenGL game under Wine or Proton and it should bring back the invisible characters, menus and UI. Any old OpenGL Windows game that assumes the default VAO in a Compatibility profile hits the same bug and takes the same fix.
• The audio wait cap and the Wayland UseTakeFocus registry value. Both act on Wine, not on the game.

What's tied to this build:

• Fix 1 (the one-byte kmyCore.dll edit) and Fix 2 (the bakinplayer.exe IL rewrite) are pinned to one kmyCore.dll (md5 68590231...). The same build patches the same way, a different version has different offsets. The scripts check the exact bytes and stop if they don't match, so running them on the wrong build does nothing bad. It just refuses.
• Fix 3 (the shader keep-alive) only applies if the game ships the same v2_vpcommon.cgh.
• The audio hook's ntdll offset (0x5b530) follows the Proton build, not the game.

To try it on another old-Bakin game:

1. Start with the hook by itself (VAO fix and audio cap). Change the hardcoded APPID=2326780 in install.sh to the new game's ID so @TMPBASE@ resolves to its prefix, then set the launcher as that game's launch options. This is usually enough to get the characters and menus back.
2. If the game also opens to a grey, empty scene, you also need fixes 1 and 2, with their offsets re-derived from that game's kmyCore.dll.
3. Fix 3 is only worth doing if the log fills with "Vertex Attribute Problem".

None of this is guaranteed on a build nobody has tested, but the VAO fix is general enough to be the first thing to reach for.

Legal

This exists for interoperability: making a legally purchased game run on Linux. No copyrighted game content is redistributed; the tools operate on your own files. The bundled ibl_brdf_lut.bmp is a standard precomputed BRDF lookup table (the Karis split-sum function), not game content. bakin_minimal.c and the scripts are MIT-licensed (see LICENSE). "RPG Developer Bakin" and the game are trademarks of their respective owners.