ruffle - RetroBIOS¶
Technical notes
Flash Player and Adobe AIR runtime written in Rust, playing SWF files of any
ActionScript version, as a desktop binary or as a WebAssembly browser build.
Versioned releases sit next to the nightlies: Batocera 43.1 compiles the
nightly-2026-01-31 tag and installs ruffle_desktop as ruffle, RetroDECK pulls
the rs.ruffle.Ruffle Flathub build. ES-DE runs it as ruffle --fullscreen
<rom>, Batocera as ruffle <rom>, RetroBat as ruffle.exe --graphics
<renderer> --force-align -q <quality> <rom>, RetroDECK as ruffle --graphics
vulkan --config /var/data/ruffle --save-directory <saves>/ruffle <rom>. The
ActionScript class library is compiled by build_playerglobal into
playerglobal_avm1.swf and playerglobal_avm2.swf and linked into the binary
from OUT_DIR (core/src/avm1/globals.rs:88, core/src/avm2/globals.rs:549), so
startup reads nothing. Locale texts, wgsl shaders, the window icon and the
OpenH264 license are embedded the same way (desktop/src/gui/locale.rs:7-12,
desktop/src/app.rs:464, render/wgpu/src/shaders.rs:30-95,
desktop/src/gui/movie.rs:44,
desktop/src/gui/dialogs/preferences_dialog.rs:517).
H.264 video is the one external dependency. external_video is a default feature and pulls ruffle_video_external with openh264 (desktop/Cargo.toml:27,84,92), and enable_openh264 defaults to true (desktop/src/preferences.rs:291,316). OpenH264Codec::load first dlopens the system sonames libopenh264.so.7, libopenh264.so.2.4.1 and libopenh264.so on Linux, then falls back to <cache>/ruffle/video/ and fetches the Cisco binary from ciscobinary.openh264.org bz2-compressed into it (video/external/src/decoder/openh264.rs:53-56,109-133,173-191, desktop/src/player.rs:234-241). Whether the library was already there or was just downloaded, its SHA-256 is checked before loading and the size is read only to format the mismatch message (video/external/src/decoder/openh264.rs:135-146), and WelsGetCodecVersion must answer 2.4.1 exactly (video/external/src/decoder/openh264.rs:46,153-166). The cache root comes from dirs::cache_dir(), ~/.cache/ruffle by default, and --cache-directory moves it (desktop/src/cli.rs:31-35,148). Without the library the player still starts: ExternalVideoBackend wraps SoftwareVideoBackend, so H.263, Screen Video and VP6 keep decoding and only H.264 streams fail (video/external/src/backend.rs:41,51-69,73-80).
Text uses system fonts. fontdb::Database::load_system_fonts() fills the database at startup (desktop/src/app.rs:433-434), and both the Flash device fonts and the egui menu bar resolve family names against it and take whatever face the host answers with (desktop/src/backends/ui.rs:321-360, desktop/src/gui/controller.rs:741-787). The face is memory-mapped and parsed by Ruffle's own rasterizer unless preferences.toml sets device_font_renderer to freetype, which routes Linux builds through FreetypeFontRenderer instead; the freetype default feature only compiles that branch, the preference selects it (desktop/src/backends/ui.rs:190-192,443-487,489-519, desktop/src/preferences/read.rs:74-75, desktop/Cargo.toml:84). The families asked for are Times New Roman, Arial, Courier New and their metric-compatible substitutes, plus the CJK, Hebrew, Arabic and Thai faces (desktop/src/player.rs:361-414, desktop/src/gui/controller.rs:620-694), and on Unix fontconfig sorts the fallback chain (desktop/src/backends/ui.rs:363-376,536-628). No name, path, size or hash is fixed anywhere. The compiled-in Noto Sans subset sits behind the default_font feature, which the web and exporter crates enable and the desktop build does not (core/src/player.rs:84-85, core/Cargo.toml:82,95, web/Cargo.toml:63-65, exporter/Cargo.toml:16, desktop/Cargo.toml:23), so on the desktop an unmatched family leaves the run without that face rather than falling back to a bundled one.
Files the player writes rather than expects: preferences.toml, bookmarks.toml and recents.toml under --config, each defaulted when absent (desktop/src/preferences.rs:54-96), .sol SharedObjects under --save-directory (frontend-utils/src/backends/storage.rs:31-60, desktop/src/cli.rs:137-138), and the log file under <cache>/ruffle/log (desktop/src/main.rs:165-176). ruffle-bundle.toml is the manifest inside a .ruf bundle, which is content alongside the .swf rather than a runtime input (frontend-utils/src/bundle/info.rs:11, frontend-utils/src/bundle.rs:42-53). mms.cfg is not implemented, the name appears only in an AVM2 error string (core/src/avm2/error_messages.rs:237).
8 files | 0 required, 8 optional | 8 in repo, 0 missing
libopenh264-2.4.1-linux64.7.so optional in repo
OpenH264 2.4.1 decoder library, Linux x86_64
- Path:
video/libopenh264-2.4.1-linux64.7.so - System: flash
- SHA256:
1392d21466bc... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:65-68,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
libopenh264-2.4.1-linux-arm64.7.so optional in repo
OpenH264 2.4.1 decoder library, Linux aarch64
- Path:
video/libopenh264-2.4.1-linux-arm64.7.so - System: flash
- SHA256:
e8ea7e42855c... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:73-76,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
libopenh264-2.4.1-linux-arm.7.so optional in repo
OpenH264 2.4.1 decoder library, Linux arm
- Path:
video/libopenh264-2.4.1-linux-arm.7.so - System: flash
- SHA256:
fd1dfb27d30b... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:69-72,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
libopenh264-2.4.1-linux32.7.so optional in repo
OpenH264 2.4.1 decoder library, Linux x86
- Path:
video/libopenh264-2.4.1-linux32.7.so - System: flash
- SHA256:
b7cf0e407f99... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:61-64,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
libopenh264-2.4.1-mac-arm64.dylib optional in repo
OpenH264 2.4.1 decoder library, macOS aarch64
- Path:
video/libopenh264-2.4.1-mac-arm64.dylib - System: flash
- SHA256:
213ff93831cf... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:81-84,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
libopenh264-2.4.1-mac-x64.dylib optional in repo
OpenH264 2.4.1 decoder library, macOS x86_64
- Path:
video/libopenh264-2.4.1-mac-x64.dylib - System: flash
- SHA256:
cc0ba518a637... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:77-80,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
openh264-2.4.1-win64.dll optional in repo
OpenH264 2.4.1 decoder library, Windows x86_64
- Path:
video/openh264-2.4.1-win64.dll - System: flash
- SHA256:
081b0c081480... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:89-92,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
openh264-2.4.1-win32.dll optional in repo
OpenH264 2.4.1 decoder library, Windows x86
- Path:
video/openh264-2.4.1-win32.dll - System: flash
- SHA256:
832701496404... - Validation: sha256
- Source:
video/external/src/decoder/openh264.rs:85-88,video/external/src/decoder/openh264.rs:104-146,video/external/src/decoder/openh264.rs:173-191
Generated on 2026-10-10T11:26:02Z