THIS PROJECT IS NOT RELATED TO SHADPS4. ALL QUESTIONS RELATED TO THIS PROJECT SHOULD BE SENT TO THE DISCORD SERVER https://discord.gg/KYZRKk9CB, NOT TO THE SHADPS4 SERVER.


# bbport — a native Linux port of Bloodborne

**English** · [Русский](README.ru.md)

bbport is the counterpart of Wine + DXVK for a single game: *Bloodborne* for PlayStation 4
(CUSA03173, game version 1.09) on an x86-64 Linux PC. The game's original executable runs
directly on the PC:

- **as in Wine**, the game's x86-64 code runs on the CPU directly, and a runtime written for
  this one game replaces the PS4 system libraries;
- **as in DXVK**, the game's graphics are translated to Vulkan — by a renderer derived from
  [shadPS4](https://github.com/shadps4-emu/shadPS4) and heavily extended for this game, including
  temporal upscaling with AMD FSR 3.1, FSR 4 and FSR 4.1.1;
- memory and the GPU's work follow the PC model on AMD GPUs by default (the new memory and
  translation model); NVIDIA and other GPUs keep the old memory model of 0.3 for now. The
  launcher's *Memory model* switches either way.

One step remains to the full Wine + DXVK model: the new model on NVIDIA as well, then removing the
old memory model (see below).

> **No game files are included.** You need your own dump of Bloodborne with update 1.09: any retail
> release (CUSA00900 in the US, CUSA03173 for the European Game of the Year edition, ...), as they
> share the same executable.
> This project is not affiliated with Sony Interactive Entertainment, FromSoftware or AMD.

**Status: experimental, playable.** The game boots, loads saves and plays (the Hunter's Dream
and several areas of Yharnam were played with it) with sound, gamepad and saving.
A full play-through has not been verified, and only one machine (Linux, AMD Radeon RX 7800 XT,
Mesa/RADV) has been tested thoroughly.

## Highlights

- **Native execution.** The eboot is converted offline into a flat memory image; PS4 libc and
  libSceFios2 are linked into it as native code. No CPU emulation and no per-instruction
  translation: the game code runs at full speed.
- **Two memory models** (launcher → *Mode → Memory and translation model*; *Auto*, the default,
  picks by GPU):
  - **The old memory model, as in 0.3 — the default on NVIDIA, Intel and others.** VRAM copies
    of the game's memory, writes tracked through page protection. With every fix made since 0.3
    (motion vectors and the upscaler, flicker with DoF on, a damaged shader cache).
  - **The new memory and translation model — the default on AMD.** The game's memory lives
    in system RAM and the GPU reads it where it is, as a PC game's buffers; data it reads often
    is kept in VRAM and given back when unused (textures after 20 s, buffers after 60 s). The
    layer's memory module tracks CPU writes to mirrored blocks to keep those copies coherent;
    it does not copy the whole GPU-visible memory. The PS4 command processor's work
    is translated into Vulkan commands rather than emulated on the CPU: memory writes
    (`WRITE_DATA`, DMA) are done by the GPU in command-stream order, and fences are written by the
    GPU itself at the end of the pipeline, at the same point of the stream as the PS4's command
    processor writes them. On AMD the game's memory is kept in a sparse buffer (the arena); on
    NVIDIA, Intel and others it goes through the layer's memory module: bound in place, VRAM
    copies as separate buffers, no sparse rebinding (NVIDIA's sparse binding froze the GPU for
    seconds); `BB_LAYER_MEMORY=1/0` chooses by hand. Tested on an RX 7800 XT. On NVIDIA it can be chosen by hand (*New*); testers' results differ by scene,
    some scenes are slower than with the old model, so it is not the default there yet. Not
    tested on Intel. Without the launcher: `BB_PC_MODEL=1/0` (unset: by GPU, as *Auto*).

  [Changes in 0.5](docs/CHANGES_0.5.md); the prereleases: [pre4](docs/CHANGES_0.5-pre4.md),
  [pre3](docs/CHANGES_0.5-pre3.md), [pre2](docs/CHANGES_0.5-pre2.md).

  Unused textures are freed in both modes, so VRAM no longer grows with every area visited.
- **Unlocked frame rate.** Community patches (`patches/Bloodborne.xml`) make the simulation
  use the real frame time; ~90 FPS at 4K with FSR 4 Balanced on an RX 7800 XT, ~150 FPS at
  1440p with FSR 4 Quality. Also 30/60/90 FPS modes.
- **Temporal upscaling built for this game.** Bloodborne has no velocity buffer, so bbport
  computes motion vectors itself: camera motion from depth and the scene matrices, and object
  motion (characters, cloth, weapons) from the vertex positions of the previous frame. The
  scene is jittered sub-pixel (Halton) and rendered at a reduced resolution; the upscaler fills
  the output (720p for the Steam Deck, 1080p, 1440p or 2160p) and the UI is drawn natively at the output resolution.
  - **FSR 3.1** (FireBurn/FSR-Vulkan).
  - **FSR 4 (INT8, model v07)** on GPUs exposing the required Vulkan shader features —
    RDNA2/3 included (see Requirements).
  - **FSR 4.1.1**: AMD's 4.1.1 DLL is recorded once under vkd3d-proton and its passes are
    replayed natively on Vulkan; the output is **bit-exact** with the DLL. Two variants, as in
    the DLL: INT8 on any GPU with the required shader features, and FP8 matrices on RDNA4 (RX
    9000; picked automatically). The assets are built on your machine from one DLL of your own
    (4.1.x): the launcher's *FSR 4.1.1 from your own AMD DLL → Choose DLL…* button (2–5 minutes,
    twice that on RDNA4; needs a recent Proton), or `tools/fsr4cap`.
  - Faster than AMD's own shaders on RDNA3: the final passes of FSR 4 and 4.1.1 were rewritten
    to store through workgroup memory (3.5× and 2.3× faster, bit-exact); FSR 4 costs ~4 ms at
    4K on an RX 7800 XT instead of ~6 ms.
- **Multi-threaded GPU command processing.** The PS4 command stream is decoded on one thread
  and draws are bound and recorded on another (two-stage pipeline), with a Vulkan recording
  thread and helper threads for memory copies. Early on the single GPU thread capped the game
  at ~26 FPS; now it runs at 90–150 FPS depending on resolution and scene.
- **Settings inside the game's own menu:** *System → Display / Effects* (after *Screen/Sound*),
  built and drawn by the game itself — output resolution, upscaler, preset, sharpness, FPS
  counter, model detail and the game's effects, in the game's language.
- **Overlay menu** (Insert or L3+R3), styled like the game's dialogs: everything above plus the
  advanced settings, with gamepad, keyboard and mouse.
- **GTK4 launcher** and an **AppImage** for the Steam Deck.

## How it differs from shadPS4

| | shadPS4 | bbport |
|---|---|---|
| Scope | General PS4 emulator, many games | One game: Bloodborne v1.09 |
| Loading | Its own ELF loader and kernel emulation at run time | The eboot is converted offline (`scripts/`) into an image with PS4 libc/Fios2 linked in; a C loader maps it and jumps into the game (loader and runtime: ~5k lines) |
| Memory | The GPU's view of PS4 memory is kept in VRAM copies, synchronized through page-protection write tracking | By default the same model (as in 0.3); in the *New memory and translation model* mode: the game's memory in system RAM, used by the GPU in place, frequently read data in VRAM, freed when unused |
| Command processor | Emulated: memory writes, DMA and fences are done by the CPU while decoding | By default the same; in the new mode translated into Vulkan commands that the GPU runs in stream order, fences written after the work has really finished |
| System libraries | Broad HLE of the PS4 OS | A small runtime (`src/runtime_*.c`) that implements exactly what Bloodborne calls: memory, threads, sync, files, audio (incl. ATRAC9), pad, saves, AppContent |
| GPU | shadPS4 video core and shader recompiler | The same core (vendored, GPL) with ~200 marked changes (`bbport:`) plus new modules: two-stage draw pipeline, render-state and texture-set memoization, render-scale proxies, motion vectors, FSR 3.1/4/4.1.1, frame capture and GPU profiler |
| GPU thread | One thread processes the whole command stream (the bottleneck in Bloodborne) | Decode and draw recording run on separate threads; the work scales with the hardware threads (Steam Deck included) |
| Upscaling | — | Temporal (FSR 3.1, FSR 4, FSR 4.1.1) with the game's own motion vectors and jitter |
| Game patches | Patch files applied by the emulator | The same community patches, compiled at start (`scripts/patches.py`); render resolution, effects and FPS from the launcher |

Without shadPS4 there would be no bbport: its renderer and shader recompiler are the base of
the graphics side.

### Wine + DXVK for one game

- **CPU.** The PS4 CPU is x86-64, so the game's code runs directly on the PC's CPU, with no
  emulation and no instruction translation.
- **System libraries.** As Wine replaces the Windows API, the bbport runtime (`src/runtime_*.c`)
  implements exactly the PS4 OS functions Bloodborne calls: memory, threads, files, audio, pad,
  saves.
- **Memory.** In the new mode, as in a PC game: the game's data in system RAM, VRAM used the way
  a PC game uses it. The mode is still experimental.
- **Graphics.** The PS4 GPU's command stream (PM4) is a recording of the game's graphics API
  calls: it is written by 99 functions of the statically linked libGnm, so decoding the stream
  and translating the calls themselves come to the same thing. GCN shaders are translated to
  SPIR-V. In the new mode the command processor's work (memory writes, DMA, fences) is
  translated into Vulkan commands as well; fences are written by the GPU itself. Resource
  descriptors (textures, buffers) are read by the translator on the CPU, as DXVK reads resource
  bindings: a PS4 texture has to be converted from the PS4 tiling into a Vulkan image before the
  draw runs, so the CPU must know its descriptor beforehand — translation, not emulation. The
  descriptor tables (the constant engine's dumps) are read only by the translator, so the CPU
  performs them. The game's occlusion queries (~60 a frame) are
  Vulkan occlusion queries; predication, `COPY_DATA` and `COND_EXEC` are translated too (check:
  `BB_PM4_SELFTEST=1`). Details:
  [docs/EMULATION_REMOVAL_PLAN.ru.md](docs/EMULATION_REMOVAL_PLAN.ru.md), "Шаг 4" (Russian).

"Port" here means a build for this one game, not a rewrite of its source code, which the project
neither has nor includes.

## Requirements

- Linux x86-64, a Vulkan 1.3 GPU. Tested: AMD RX 7800 XT with Mesa 26 (RADV).
  The *New memory and translation model* mode is not tested on NVIDIA yet.
  FSR 4 / 4.1.1 require shader Float16, Int8/Int16, integer dot products, linear compute
  derivatives and extended storage image formats; FSR 4.1.1 additionally requires
  `VK_VALVE_shader_mixed_float_dot_product`. Unsupported choices fall back to FSR 3.1
  before the first frame and are disabled in the in-game menu.
- Your decrypted game dump: the `CUSA03173` folder (eboot.bin, sce_module, ...), version 1.09.
  A dumped update is a separate folder: copy it over the base game, replacing files. The base
  game alone (1.00) crashes at start (guest offset 0x20348b8); the launcher and `run.sh` check
  the executable and say what is missing (`BB_SKIP_GAME_CHECK=1` skips the check). The other
  retail releases (the US `CUSA00900`, the Asian `CUSA03023`, ...) run the same 1.09 executable. Some dumps ship it
  with Lance McDonald's 60 fps patch baked in, which crashes when the gestures menu opens: the
  check asks for a clean eboot.bin then (bbport has its own 60 fps).
- To build: GCC, CMake, Ninja, Python 3, glslang, SDL3, Vulkan headers and the libraries in
  `shell.nix`. With [Nix](https://nixos.org) everything comes from `shell.nix` automatically.

## Build and run

```bash
git clone --recursive https://github.com/deadinside28/bloodborne_pc.git bbport && cd bbport
bash build.sh                        # builds out/bb-probe and out/gpu/libbbgpu.so
BB_GAME_DIR=/path/to/CUSA03173 bash run.sh
```

or the launcher (pick the game folder, settings, *Start*):

```bash
bash launcher/bb-launcher.sh         # launcher/install-desktop.sh adds it to the app menu
```

By default the game folder is expected next to the repository (`../CUSA03173`). Saves and the
shader cache go to `user/` (the launcher lets you choose another folder); settings to
`bbport.ini`. A gamepad is used through SDL3 (the launcher's *Controls → Controller* picks one
when several are connected; `BB_GAMEPAD=<GUID or part of the name>`). The keyboard works too,
also next to a connected gamepad (the Steam Deck always has one); both are remapped in the
launcher (*Controls*). The character name is typed on the keyboard in a box over the game.
The touchpad: its left half (Tab, Back/Select) opens the gestures, the right half (Backspace)
the key items. There is no PSN: the *Play online / offline* screen is skipped and the game opens
its main menu offline (a game patch; the launcher's *Game effects → Skip the “play online / offline” choice*,
`BB_SKIP_NETWORK_CHOICE=0` shows it). With several monitors, *Screen → Monitor* in the launcher
(`BB_DISPLAY=<number or part of the name>`) picks the one for the game.

**Resolution and preset changes:** for outputs other than 1080p (720p on the Steam Deck,
1440p, 4K) the whole game renders at the preset's resolution, set by a patch at start — the
fastest path. Changing the output or the preset in the in-game menu then needs *Apply and
restart the game*. The *Live resolution changes* setting (launcher, in-game menu,
`bbport.ini` `live_resolution=0|1|auto`; **off by default**) instead keeps the game at
1080p internally and scales its render targets at run time, so 720p/1080p/1440p/4K and the
presets switch without a restart. It costs more: the game then believes it renders 1080p
and draws more (e.g. ~8× more small lights), and some targets are copied between sizes —
use it on strong desktop GPUs only (`auto` turns it on for discrete GPUs with 8+ GB that are
not pre-Turing NVIDIA). 1080p output and TAA always use the live path.

**TAA:** a separate native-resolution temporal AA mode in the launcher and overlay,
switchable live without an FSR model. The saved FSR preset is restored when returning
to FSR. FSR Native AA adds reconstruction on top of full-resolution rendering and can
be slower than disabling AA. TAA also adds work compared with no temporal AA.
The RCAS switch and the 0–2 sharpness control also work with TAA. Sharpening runs after
temporal accumulation and leaves its history and HUD unchanged.

**Mods:** the launcher accepts separate loose-file mod folders (with `dvdroot_ps4/`, an extra
wrapper folder, or the game folders such as `chr/` directly; file name case does not matter),
with enable switches and load order. A sibling `CUSA03173-mods/` overlay also works.
The original game is preserved; later mods override conflicting files.
**Third-party patches:** shadPS4-format XML patch files in the data directory's `patches/`,
switched on and off in the launcher. See [mods and patches](docs/MODS.md).
**DLC:** put your add-on dumps in `user/addcont/<title id>/<entitlement label>/` (shadPS4's
layout, e.g. `user/addcont/CUSA03173/SPEXPANSIONDLC03` for The Old Hunters): each folder there is
reported to the game as an installed add-on.

**Launcher language:** Russian, English, Brazilian Portuguese or Simplified Chinese (follows the system language by default).

**Free camera and game debug menu** (v1.09): enable the corresponding switches in the
launcher or in-game menu and restart. Free camera uses Lance McDonald's
[GoldHEN patch](https://github.com/GoldHEN/GoldHEN_Patch_Repository/blob/main/patches/xml/Bloodborne-Orbis.xml):
hold Cross and press L3 to cycle modes (keyboard: hold Space and press Z). It needs no fonts
and conflicts with *Enemy Control*.
For the game debug menu, install `DbgFont14h.ccm` and `DbgFont14h.tpf` from
[Debug Menu and XML Patch](https://www.nexusmods.com/bloodborne/mods/253) into the game's
`dvdroot_ps4/font/` first. Startup rejects missing or empty font files instead of launching
the unsafe patch. Open it with the left touchpad / Tab (with the debug menu on, the left half
no longer opens the gestures); Backspace is the right touchpad.
Touch coordinates are forwarded from SDL gamepads; Back/Select emulates a left click on
pads without a touch surface. The port's settings menu remains Insert / L3+R3.

GPU occlusion queries still use synthetic pixel counters (`PixelPipeStatDump`), and
`IT_SET_PREDICATION` is unimplemented. Free camera allows visual investigation; it does
not implement GPU occlusion culling.

**Upscaler assets** (not included; FSR 3.1 needs none):

```bash
bash tools/fetch_fsr4_assets.sh      # FSR 4 v07 (MIT, built from AMD's source by Q2RTX)
# FSR 4.1.1, from your own AMD DLLs (e.g. OptiScaler's FSR4_LATEST), needs GE-Proton 10 or newer:
bash tools/fsr4cap/build_assets.sh <amd_fidelityfx_upscaler_dx12.dll>
```

**FSR 4.1.1 from your own DLL.** The easiest way is the launcher: *Upscaler → FSR 4.1.1 from your
own AMD DLL → Choose DLL…*, then pick `amd_fidelityfx_upscaler_dx12.dll` version 4.1.x: from
OptiScaler's `FSR4_LATEST` folder or from a game with FSR 4.1. That one file is enough: AMD's DLL
exports the FidelityFX API itself, so no loader is needed (only a DLL without these exports would
be recorded through `amd_fidelityfx_loader_dx12.dll`, and the launcher would ask for it). The DLL is checked at once,
without a long capture; these do not fit: AMD's official FSR 4.0.x (e.g. Pragmata's 4.0.3 —
AMD enables it on RDNA4 only, and under Proton it does not start on other GPUs) and community
builds (4.0.2b, 4.1.1b and similar OptiScaler INT8 builds: another model and pass count). Then
the DLL runs under Proton and is recorded at 20 sizes (progress in the row and in the *Log* tab;
on RDNA4 a second time, for the FP8 variant),
the passes are translated to SPIR-V, and FSR 4.1.1 is selected. The Proton build is picked
automatically — the first under which the DLL enables FSR 4.1: GE-Proton 10 or newer,
Proton-CachyOS, Proton Experimental (tested: GE-Proton 11, Proton-CachyOS 11, Experimental of
October 2026; Steam's Proton 11.0 and GE-Proton 9 do not). It runs in the Steam runtime it
requires (Steam installs it the first time any game runs with that Proton), or through
umu-launcher when installed. On NixOS umu-launcher comes from `nix-shell` (downloaded the first
time, ~1.7 GB); the AppImage runs the recording on the system itself, through the user's systemd
(`systemd-run --user`), since the system's `/nix` is out of its sight. Recording on the Steam Deck is not verified yet; if the DLL does not
enable FSR 4.1 there, build on a PC and copy the `fsr4_411` folder. The same from the command
line: the launcher's (and the AppImage's) `--build-fsr411 <DLL>`.

**DLSS (NVIDIA GeForce RTX).** NVIDIA's DLSS SDK is not included: check out
[github.com/NVIDIA/DLSS](https://github.com/NVIDIA/DLSS) (`include/` and `lib/Linux_x86_64` are
enough) and build with `DLSS_SDK_ROOT=/path/to/DLSS bash build.sh`. That also builds the bridge
`out/libbbport_dlss.so` (`gpu/dlss_bridge`, the only code that uses the SDK) and copies NVIDIA's
`libnvidia-ngx-dlss.so.<version>` next to `out/bb-probe`; the driver provides the rest. Then pick
*DLSS* in the launcher or the in-game menu: the preset sets the render size, Native AA is DLAA.
DLSS gets the inputs FSR 3.1 gets (scene color, depth, motion vectors, jitter). Without the
libraries, on other GPUs or with `BB_DLSS=0` it is listed as unavailable, and a DLSS setting falls
back to FSR 3.1.

The AppImage built with `DLSS_SDK_ROOT` carries the bridge and NVIDIA's library (NVIDIA's RTX SDK
license allows that in an application; its text is `NVIDIA-DLSS-LICENSE.txt` in the package). A
newer `libnvidia-ngx-dlss.so.<version>` (from the SDK's `lib/Linux_x86_64/rel`) is chosen in the
launcher: *Upscaler → DLSS: NVIDIA's library → Choose a file…*, as the FSR 4.1.1 DLL; it is
copied to `<user>/dlss/`, which the game prefers. A game's `nvngx_dlss.dll` is the Windows
library: NVIDIA's Linux driver does not load it.

From source the script takes its tools from the system (MinGW GCC, CMake, Ninja, Python 3,
SPIRV-Tools, Git) or from Nix; the AppImage has them prebuilt.

**FP8 on RDNA4.** When vkd3d-proton offers FP8 cooperative matrices (RDNA4), the DLL runs
another variant of its passes: other shaders and weights, other dispatch sizes. The build records
both, INT8 into `fsr4_411/` and FP8 into `fsr4_411/fp8/`, and the game picks FP8 itself when the
GPU has FP8 matrices (`VK_EXT_shader_float8`); the log says `Upscaler: FSR 4.1.1 replay, FP8 …`.
`BB_FSR411_VARIANT=int8` forces INT8. Checked on an RX 7800 XT through vkd3d-proton's FP16
emulation of FP8 (`BB_FSR4CAP_FP8=1` records it there too, `fp8emu/`): bit-exact with the DLL;
**not yet run on RDNA4 hardware.**

**AppImage** (Steam Deck): `bash build.sh && bash packaging/appimage.sh` →
`dist/Bloodborne-bbport-x86_64.AppImage`; data in `~/.local/share/bbport`, `--play` starts the
game without the launcher window (Game Mode). FSR 4.1.1 models are not packaged: build them with
the launcher's button (see above); they go to `~/.local/share/bbport/fsr4_411`
(`BB_PACKAGE_FSR411=1` bundles a local `fsr4_411` into an AppImage for your own devices). On the Steam Deck pick the 1280×720 output (the
game is 16:9; on the 1280×800 screen it gets thin bars).

**Adding the AppImage to Steam** (*Add a Non-Steam Game*) needs no options; the compatibility tool
does not matter. (Steam preloads its overlay into every non-Steam game; the AppImage removes it
before its own programs start, so the Steam overlay is not shown in the game.) Where Steam
runs games without FUSE (NixOS: Steam's FHS sandbox; the AppImage then exits with *Cannot mount
AppImage*), set the launch options to

```
TMPDIR=$HOME/.cache APPIMAGE_EXTRACT_AND_RUN=1 NO_CLEANUP=1 %command%
```

The AppImage then unpacks itself (~2 GB, `~/.cache/appimage_extracted_*`) on the first start
(~10 s) and reuses that copy afterwards; a new AppImage version gets a new copy, the old one can
be deleted. Without `TMPDIR` it would unpack into Steam's `/tmp`, which is in RAM there. Add
` --play` after `%command%` to skip the launcher.

**NVIDIA in the AppImage:** startup discovers the host's installed 64-bit NVIDIA Vulkan ICD
and exposes its vendor libraries alongside the bundled AMD/Intel drivers. This keeps the
NVIDIA userspace driver matched to the host kernel module. Standard Linux distributions keep
these libraries under `/usr/lib*`; on NixOS the AppImage's internal `/nix/store` may hide them.
In that case copy the NVIDIA libraries into an accessible directory and set
`BB_NVIDIA_LIB_DIR=/path/to/libraries` (the NVIDIA manifest must also be accessible).
With the host's NVIDIA driver the AppImage also passes the host's EGL vendor files, NVIDIA's
first (`__EGL_VENDOR_LIBRARY_FILENAMES`; without them NVIDIA's ICD gave no `vkCreateInstance` on
some hosts, #107; `BB_NVIDIA_EGL=0`: off). Explicit `VK_DRIVER_FILES`/`VK_ICD_FILENAMES` overrides are preserved. Diagnose drivers inside
the package with:

```bash
./Bloodborne-bbport-x86_64.AppImage --vulkan-info 2>&1 | tee bbport-vulkan.log
```

A user reported successful startup with FSR 3 on a GTX 1060 6GB (Fedora 44, NVIDIA
580.178.04); selecting FSR 4 caused a black window. Use FSR 3 on this configuration.

MangoHud is bundled in the AppImage; enable its checkbox in the launcher. If MangoHud is also
installed system-wide, or Steam's performance overlay is on (Steam Deck game mode), only one
overlay is drawn (two drew doubled, offset text).
When running from source, install MangoHud separately. A diagnostic launch with
`VK_LOADER_LAYERS_DISABLE=~implicit~` also disables MangoHud.

Useful variables: `BB_FRAME_STATS=1` (frame statistics, including a `Memory:` line: VRAM, GTT,
RSS, images and guest blocks in VRAM), `BB_PC_MODEL=1` (the new memory and translation model,
0, the old model as in 0.3, is the default), `BB_ANISO=N` (anisotropic filtering of scene textures; 16 by
default, 0 = the game's own),
`BB_GC_IDLE_SECONDS=N` / `BB_VRAM_IDLE_SECONDS=N` (how long unused textures / buffers stay in VRAM;
20 / 60), `BB_BREADCRUMBS=0` (no GPU breadcrumbs; with them a GPU hang names the draw or dispatch
it is stuck in), `BB_GPU_PROFILE=1` (GPU time per
pass), `BB_FSR4_PROFILE=1` (GPU time per FSR 4 pass), `BB_UPSCALER=taa|fsr3|fsr4|fsr411|off|none`,
`BB_FRAMES_AHEAD=N` (how many frames the GPU command thread may run ahead of the GPU; 1 by default,
0 = unbounded), `BB_PRESENT_THREAD=0` (present on the vblank thread, as before),
`BB_LIVE_RES=1` (live resolution changes instead of the startup patch for outputs other than 1080p),
`BB_PAD_RECORD=file` / `BB_PAD_REPLAY=file` (record a route with F9, replay it in scripted tests),
`BB_GC_BUDGET_MB=N` (texture cache budget, as on integrated GPUs), `BB_VRAM_LIMIT_MB=N` (the VRAM
budget taken as at most N MiB: checks the behaviour of cards with little VRAM), `BB_ASYNC_PIPELINES=0`
(new pipelines compile at once and the game waits; by default in the background), `BB_PRESENT_DUMP_TRIGGER=file`
with `BB_PRESENT_DUMP_COUNT=N` (dump N consecutive presented frames),
`BB_FSR411_VARIANT=int8|fp8|fp8emu` (FSR 4.1.1 variant; by default FP8 where the GPU has FP8
matrices), `BB_READBACKS=0|1|2` (reads of GPU-written memory by the game: 1 by default, 2
precise and slow, 0 off).
More in [docs/](docs); recent changes: [docs/CHANGES_0.4.md](docs/CHANGES_0.4.md) (in Russian),
[docs/CHANGES_2026-10-06.md](docs/CHANGES_2026-10-06.md).

**Online play (shadNet).** A separate module, `out/gpu/libbbnet.so` (`gpu/bbnet`: shadPS4's network
and PSN libraries from shadp2p, a shadPS4 fork, with the shadNet client), built when protobuf,
nlohmann_json, OpenSSL, zlib and miniupnpc are there (`shell.nix`) and included in the AppImage.
The launcher's *Online* page turns it on (`BB_ONLINE=1`): messages, bloodstains and ghosts come
from The Hunter's Dream, bells and summons go through a shadNet server (`srv.shadps4.net:31313` by
default) with a shadNet account (Online ID and password). Offline the module is never loaded; a
build without it plays offline only.

## Repository layout

| Path | Contents |
|---|---|
| `src/` | Loader (`probe.c`) and the HLE runtime |
| `scripts/` | Offline preparation of the game image, module linking, patch compiler |
| `gpu/` | Renderer library: vendored shadPS4 video core with this port's changes (`gpu/VENDOR.txt`), shims, ImGui menu, FSR 4.1.1 runtime (`gpu/shadps4/video_core/renderer_vulkan/fsr411`) |
| `launcher/`, `packaging/` | GTK4 launcher; Nix package and AppImage |
| `patches/` | Community patches for Bloodborne |
| `tools/` | Developer tools: scripted runs, A/B toggles, FSR benchmark helpers, FSR 4 shader rewrites, `fsr4cap` (FSR 4.1.1 recording/extraction) |
| `tests/` | Loader, runtime, patch and renderer tests |
| `docs/` | Design notes and measurements ([upscaler](docs/upscaler.md), [parallel GPU](docs/parallel_gpu.md), [motion vectors](docs/motion_vectors.md), [roadmap](docs/ROADMAP.md)) |

Tests: `bash build.sh --test`, `python3 -m unittest discover -s tests`, and
`ninja -C out/gpu motion-history-test ui-composition-test scene-resolution-test motion-shader-test settings-test`.

## Roadmap

- The new memory and translation model on by default on NVIDIA too, once it is as fast there;
  the old model is removed after that.
- Textures as objects created at load time (less guessing by address, uploads outside the
  frame).
- Shaders translated ahead of time, at install, not during play.
- More CPU parallelism in GPU command processing (split the draw-recording stage further),
  scaling to all hardware threads — most important for the Steam Deck.
- Async compute for the upscaler (the frame is GPU-bound at 4K).
- XeSS (super resolution) and XeFG frame generation through a Wine helper sharing Vulkan
  memory (a memory-bridge prototype is in `tools/bridge_helper`); inputs exposed so that OptiScaler-style mapping works.
- Frame generation (FSR 3.1 FG first), reactive and transparency masks for particles and fog.
- Fix the races in AMD's FSR 4.1.1 shaders at output widths that are not multiples of 64
  (e.g. 1600×900), as already done for the left-edge race in FSR 4 v07 at 1080p.
- Steam Deck validation of the AppImage; HDR output.

## Credits and licenses

bbport is licensed under the **GNU GPL v2 or later** ([LICENSE](LICENSE)) — it contains code
from shadPS4 (GPL-2.0-or-later). Third-party components keep their licenses:
[shadPS4](https://github.com/shadps4-emu/shadPS4) video core and shader recompiler (GPL-2.0+),
[sirit](https://github.com/shadps4-emu/sirit), [half](https://half.sourceforge.net/),
[FSR-Vulkan](https://github.com/FireBurn/FSR-Vulkan) by FireBurn (MIT; FSR 3.1 on Vulkan and the
FSR 4 v07 provider), AMD FidelityFX SDK (MIT), [LibAtrac9](https://github.com/Thealexbarney/LibAtrac9)
(MIT), [Dear ImGui](https://github.com/ocornut/imgui) (MIT), DejaVu fonts,
[dxil-spirv](https://github.com/HansKristian-Work/dxil-spirv) (MIT, used to build the
FSR 4.1.1 assets). Game patches by Kyo, Lance McDonald, auser1337, illusion, emoose and other
community members (`patches/Bloodborne.xml`). The DLSS bridge (`gpu/dlss_bridge`, MIT) and
loader come from [Supermedo's Windows port](https://github.com/Supermedo/bloodborne_pc), adapted
from [IFreemz/shadPS4-Bloodborne-DLSS-FSR](https://github.com/IFreemz/shadPS4-Bloodborne-DLSS-FSR).
AMD's FSR 4 DLLs and model data and NVIDIA's DLSS SDK and libraries are not distributed here.