feat(obs): vendor the OBS plugin in-tree under cpp/obs

CLAUDE.md

@@ -88,6 +88,9 @@ Key architectural rule: The CDN/relay does not know anything about media. Anythi
                       # CI mirrors them to moq-dev/moq-{swift,kotlin,go}
                       # on each moq-ffi-v* tag.
 
+/cpp/                 # C/C++ consumers of libmoq
+  obs/               # OBS Studio plugin (CMake; links libmoq via MOQ_LOCAL). GPL-2.0.
+
 /demo/                # Demos and test media
   boy/               # MoQ Boy demo (ROM hosting, orchestration justfile)
   relay/             # Relay server configs (relay.toml, root.toml, leaf*.toml)
@@ -193,6 +196,7 @@ Changes in one area usually need matching updates elsewhere, including docs. If
 | `rs/moq-relay` config/behavior | `doc/bin/relay/` |
 | `rs/moq-cli` | `doc/bin/cli.md` |
 | `rs/moq-gst` | `doc/bin/gstreamer.md` |
+| `rs/libmoq` C ABI (`moq.h`) | `cpp/obs/src`, `doc/bin/obs.md` |
 | `js/{watch,publish}` UI/API | `demo/web` if it consumes the API |
 
 ## Branch Targeting

cpp/obs/.clang-format

@@ -0,0 +1,209 @@
+# please use clang-format version 16 or later
+
+Standard: c++17
+AccessModifierOffset: -8
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands: true
+AlignTrailingComments: true
+AllowAllArgumentsOnNextLine: false
+AllowAllConstructorInitializersOnNextLine: false
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Inline
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLambdasOnASingleLine: Inline
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: false
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterClass: false
+  AfterControlStatement: false
+  AfterEnum: false
+  AfterFunction: true
+  AfterNamespace: false
+  AfterObjCDeclaration: false
+  AfterStruct: false
+  AfterUnion: false
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  IndentBraces: false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Custom
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializers: BeforeColon
+BreakStringLiterals: false  # apparently unpredictable
+ColumnLimit: 120
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+ConstructorInitializerIndentWidth: 8
+ContinuationIndentWidth: 8
+Cpp11BracedListStyle: true
+DerivePointerAlignment: false
+DisableFormat: false
+FixNamespaceComments: true
+ForEachMacros:
+  - 'json_object_foreach'
+  - 'json_object_foreach_safe'
+  - 'json_array_foreach'
+  - 'HASH_ITER'
+IncludeBlocks: Preserve
+IndentCaseLabels: false
+IndentPPDirectives: None
+IndentWidth: 8
+IndentWrappedFunctionNames: false
+KeepEmptyLinesAtTheStartOfBlocks: true
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 8
+ObjCSpaceAfterProperty: true
+ObjCSpaceBeforeProtocolList: true
+
+PenaltyBreakAssignment: 10
+PenaltyBreakBeforeFirstCallParameter: 30
+PenaltyBreakComment: 10
+PenaltyBreakFirstLessLess: 0
+PenaltyBreakString: 10
+PenaltyExcessCharacter: 100
+PenaltyReturnTypeOnItsOwnLine: 60
+
+PointerAlignment: Right
+ReflowComments: false
+SkipMacroDefinitionBody: true
+SortIncludes: false
+SortUsingDeclarations: false
+SpaceAfterCStyleCast: false
+SpaceAfterLogicalNot: false
+SpaceAfterTemplateKeyword: false
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles: false
+SpacesInCStyleCastParentheses: false
+SpacesInContainerLiterals: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+StatementMacros:
+  - 'Q_OBJECT'
+TabWidth: 8
+TypenameMacros:
+  - 'DARRAY'
+UseTab: ForContinuationAndIndentation
+---
+Language: ObjC
+AccessModifierOffset: 2
+AlignArrayOfStructures: Right
+AlignConsecutiveAssignments: None
+AlignConsecutiveBitFields: None
+AlignConsecutiveDeclarations: None
+AlignConsecutiveMacros:
+  Enabled: true
+  AcrossEmptyLines: false
+  AcrossComments: true
+AllowShortBlocksOnASingleLine: Never
+AllowShortEnumsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLambdasOnASingleLine: None
+AttributeMacros: ['__unused', '__autoreleasing', '_Nonnull', '__bridge']
+BitFieldColonSpacing: Both
+#BreakBeforeBraces: Webkit
+BreakBeforeBraces: Custom
+BraceWrapping:
+  AfterCaseLabel: false
+  AfterClass: true
+  AfterControlStatement: Never
+  AfterEnum: false
+  AfterFunction: true
+  AfterNamespace: false
+  AfterObjCDeclaration: false
+  AfterStruct: false
+  AfterUnion: false
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  BeforeLambdaBody: false
+  BeforeWhile: false
+  IndentBraces: false
+  SplitEmptyFunction: false
+  SplitEmptyRecord: false
+  SplitEmptyNamespace: true
+BreakAfterAttributes: Never
+BreakArrays: false
+BreakBeforeConceptDeclarations: Allowed
+BreakBeforeInlineASMColon: OnlyMultiline
+BreakConstructorInitializers: AfterColon
+BreakInheritanceList: AfterComma
+ColumnLimit: 120
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+EmptyLineAfterAccessModifier: Never
+EmptyLineBeforeAccessModifier: LogicalBlock
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
+IndentAccessModifiers: false
+IndentCaseBlocks: false
+IndentCaseLabels: true
+IndentExternBlock: Indent
+IndentGotoLabels: false
+IndentRequiresClause: true
+IndentWidth: 4
+IndentWrappedFunctionNames: true
+InsertBraces: false
+InsertNewlineAtEOF: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+LambdaBodyIndentation: Signature
+NamespaceIndentation: All
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 4
+ObjCBreakBeforeNestedBlockParam: false
+ObjCSpaceAfterProperty: true
+ObjCSpaceBeforeProtocolList: true
+PPIndentWidth: -1
+PackConstructorInitializers: NextLine
+QualifierAlignment: Leave
+ReferenceAlignment: Right
+RemoveSemicolon: false
+RequiresClausePosition: WithPreceding
+RequiresExpressionIndentation: OuterScope
+SeparateDefinitionBlocks: Leave
+ShortNamespaceLines: 1
+SortIncludes: false
+#SortUsingDeclarations: LexicographicNumeric
+SortUsingDeclarations: true
+SpaceAfterCStyleCast: true
+SpaceAfterLogicalNot: false
+SpaceAroundPointerQualifiers: Default
+SpaceBeforeCaseColon: false
+SpaceBeforeCpp11BracedList: true
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceBeforeSquareBrackets: false
+SpaceInEmptyBlock: false
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 2
+SpacesInConditionalStatement: false
+SpacesInLineCommentPrefix:
+  Minimum: 1
+  Maximum: -1
+Standard: c++17
+TabWidth: 4
+UseTab: Never

cpp/obs/.gersemirc

@@ -0,0 +1,8 @@
+# yaml-language-server: $schema=https://raw.githubusercontent.com/BlankSpruce/gersemi/master/gersemi/configuration.schema.json
+
+definitions: []
+line_length: 120
+indent: 2
+list_expansion: favour-inlining
+unsafe: false
+warn_about_unknown_commands: false

cpp/obs/.gitignore

@@ -0,0 +1,11 @@
+# CMake build trees (per the platform presets) and CPack output.
+build_macos/
+build_x64/
+build_x86_64/
+release/
+
+# Downloaded OBS sources + prebuilt obs-deps/Qt6 (macOS/Windows buildspec).
+.deps/
+
+# Generated build counter.
+cmake/.CMakeBuildNumber

cpp/obs/CMakeLists.txt

@@ -0,0 +1,119 @@
+cmake_minimum_required(VERSION 3.28)
+
+include("${CMAKE_CURRENT_SOURCE_DIR}/cmake/common/bootstrap.cmake" NO_POLICY_SCOPE)
+
+project(${_name} VERSION ${_version})
+
+option(ENABLE_FRONTEND_API "Use obs-frontend-api for UI functionality" OFF)
+option(ENABLE_QT "Use Qt functionality" OFF)
+
+include(compilerconfig)
+include(defaults)
+include(helpers)
+
+add_library(obs-moq MODULE)
+
+if(${BUILD_PLUGIN})
+  find_package(libobs REQUIRED)
+  # FFmpeg dependency
+  include(FindPkgConfig)
+  pkg_check_modules(FFMPEG REQUIRED libavcodec libavutil libswscale libswresample)
+  target_include_directories(obs-moq PRIVATE ${FFMPEG_INCLUDE_DIRS})
+  target_link_directories(obs-moq PRIVATE ${FFMPEG_LIBRARY_DIRS})
+  target_link_libraries(obs-moq PRIVATE ${FFMPEG_LIBRARIES})
+else()
+  find_package(FFmpeg REQUIRED avcodec avutil swscale swresample)
+  target_link_libraries(obs-moq PRIVATE FFmpeg::avcodec FFmpeg::avutil FFmpeg::swscale FFmpeg::swresample)
+endif()
+
+target_link_libraries(obs-moq PRIVATE OBS::libobs)
+
+option(MOQ_LOCAL "Path to moq repo for local development" "")
+
+if(MOQ_LOCAL)
+  add_subdirectory(${MOQ_LOCAL}/rs/libmoq moq)
+  target_link_libraries(obs-moq PRIVATE moq)
+else()
+  include(FetchContent)
+  FetchContent_Declare(
+    moq
+    URL
+      https://github.com/moq-dev/moq/releases/download/libmoq-v${MOQ_VERSION}/moq-${MOQ_VERSION}-${MOQ_TARGET}.${MOQ_ARCHIVE}
+  )
+  FetchContent_MakeAvailable(moq)
+
+  find_package(moq REQUIRED PATHS ${moq_SOURCE_DIR} NO_DEFAULT_PATH)
+  target_link_libraries(obs-moq PRIVATE moq::moq)
+endif()
+
+# The obs-deps Qt6 build references the AGL framework transitively (via
+# WrapOpenGL), but recent macOS SDKs ship no linkable AGL binary -- it exists
+# only in the runtime dyld shared cache. Generate a stub whose install name
+# points at the real framework so the link succeeds; dyld resolves AGL at load.
+if(
+  (ENABLE_QT OR ENABLE_FRONTEND_API)
+  AND APPLE
+  AND NOT EXISTS "${CMAKE_OSX_SYSROOT}/System/Library/Frameworks/AGL.framework/Versions/A/AGL"
+)
+  set(_agl_stub_dir "${CMAKE_BINARY_DIR}/agl-stub")
+  set(_agl_stub_lib "${_agl_stub_dir}/AGL.framework/AGL")
+  if(NOT EXISTS "${_agl_stub_lib}")
+    file(MAKE_DIRECTORY "${_agl_stub_dir}/AGL.framework")
+    set(_agl_arch_flags "")
+    foreach(_arch IN LISTS CMAKE_OSX_ARCHITECTURES)
+      list(APPEND _agl_arch_flags "-arch" "${_arch}")
+    endforeach()
+    execute_process(
+      COMMAND
+        xcrun clang -dynamiclib ${_agl_arch_flags} -install_name /System/Library/Frameworks/AGL.framework/Versions/A/AGL
+        -o "${_agl_stub_lib}" -x c /dev/null
+      RESULT_VARIABLE _agl_stub_result
+    )
+    if(NOT _agl_stub_result EQUAL 0)
+      message(WARNING "Failed to build AGL stub (${_agl_stub_result}); Qt link may fail")
+    endif()
+  endif()
+  target_link_options(obs-moq PRIVATE "-F${_agl_stub_dir}")
+endif()
+
+if(ENABLE_FRONTEND_API)
+  find_package(obs-frontend-api REQUIRED)
+  target_link_libraries(obs-moq PRIVATE OBS::obs-frontend-api)
+endif()
+
+if(ENABLE_QT)
+  find_package(Qt6 COMPONENTS Widgets Core)
+  target_link_libraries(obs-moq PRIVATE Qt6::Core Qt6::Widgets)
+  target_compile_options(
+    obs-moq
+    PRIVATE $<$<C_COMPILER_ID:Clang,AppleClang>:-Wno-quoted-include-in-framework-header -Wno-comma>
+  )
+  set_target_properties(
+    obs-moq
+    PROPERTIES AUTOMOC ON AUTOUIC ON AUTORCC ON
+  )
+endif()
+
+target_sources(
+  obs-moq
+  PRIVATE
+    src/obs-moq.cpp
+    src/moq-output.h
+    src/moq-service.h
+    src/moq-output.cpp
+    src/moq-service.cpp
+    src/moq-source.cpp
+    src/moq-source.h
+)
+
+# The dock requires both the frontend API (to register it) and Qt (to build it).
+if(ENABLE_FRONTEND_API AND ENABLE_QT)
+  target_sources(obs-moq PRIVATE src/moq-dock.cpp src/moq-dock.h)
+  target_compile_definitions(obs-moq PRIVATE MOQ_FRONTEND_ENABLED MOQ_VERSION_STRING="${MOQ_VERSION}")
+endif()
+
+if(${BUILD_PLUGIN})
+  set_target_properties_plugin(obs-moq PROPERTIES OUTPUT_NAME ${_name})
+else()
+  set_target_properties_obs(obs-moq PROPERTIES FOLDER plugins PREFIX "")
+endif()