livekit_bridge: An ergonomic interface into the Livekit C++ SDK

.gitignore

@@ -8,6 +8,7 @@ out
 build/
 build-debug/
 build-release/
+release/
 vcpkg_installed/
 # Generated header
 include/livekit/build.h
@@ -17,6 +18,7 @@ docs/html/
 docs/latex/
 .vs/
 .vscode/
+.cursor/
 # Compiled output
 bin/
 lib/

CMakeLists.txt

@@ -12,6 +12,7 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
 option(LIVEKIT_BUILD_EXAMPLES "Build LiveKit examples" OFF)
 option(LIVEKIT_BUILD_TESTS "Build LiveKit tests" OFF)
+option(LIVEKIT_BUILD_BRIDGE "Build LiveKit Bridge (simplified high-level API)" OFF)
 
 # vcpkg is only used on Windows; Linux/macOS use system package managers
 if(WIN32)
@@ -639,6 +640,9 @@ if(LIVEKIT_BUILD_TESTS)
   add_subdirectory(src/tests)
 endif()
 
+# Build the LiveKit C++ bridge
+add_subdirectory(bridge)
+
 add_custom_target(clean_generated
   COMMAND ${CMAKE_COMMAND} -E rm -rf "${PROTO_BINARY_DIR}"
   COMMENT "Clean generated protobuf files"

README.md

@@ -25,6 +25,9 @@ This page covers how to build and install the LiveKit C++ Client SDK for real-ti
 
 > **Note**: If the SDK was built with Protobuf 6.0+, you also need `libabsl-dev` (Linux) or `abseil` (macOS).
 
+## Prerequisites
+- install livekit-cli by following the (official livekit docs)[https://docs.livekit.io/intro/basics/cli/start/]
+
 ## 🧩 Clone the Repository
 
 Make sure to initialize the Rust submodule (`client-sdk-rust`):
@@ -328,4 +331,4 @@ In some cases, you may need to perform a full clean that deletes all build artif
 CPP SDK is using clang C++ format
 ```bash
 brew install clang-format
-```
+```

bridge/CMakeLists.txt

@@ -0,0 +1,124 @@
+cmake_minimum_required(VERSION 3.20)
+
+project(livekit_bridge LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+add_library(livekit_bridge SHARED
+  src/livekit_bridge.cpp
+  src/bridge_audio_track.cpp
+  src/bridge_video_track.cpp
+  src/bridge_room_delegate.cpp
+  src/bridge_room_delegate.h
+)
+
+if(WIN32)
+  set_target_properties(livekit_bridge PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS ON)
+endif()
+
+target_include_directories(livekit_bridge
+  PUBLIC
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+    $<INSTALL_INTERFACE:include>
+  PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}/src
+)
+
+# Link against the main livekit SDK library (which transitively provides
+# include paths for livekit/*.h and links livekit_ffi).
+target_link_libraries(livekit_bridge
+  PUBLIC
+    livekit
+)
+
+if(MSVC)
+  target_compile_options(livekit_bridge PRIVATE /permissive- /Zc:__cplusplus /W4)
+else()
+  target_compile_options(livekit_bridge PRIVATE -Wall -Wextra -Wpedantic)
+endif()
+
+# --- Tests ---
+# Bridge tests default to OFF. They are automatically enabled when the parent
+# SDK tests are enabled (LIVEKIT_BUILD_TESTS=ON), e.g. via ./build.sh debug-tests.
+option(LIVEKIT_BRIDGE_BUILD_TESTS "Build bridge unit tests" OFF)
+
+if(LIVEKIT_BRIDGE_BUILD_TESTS OR LIVEKIT_BUILD_TESTS)
+  add_subdirectory(tests)
+endif()
+
+# --- Examples ---
+option(LIVEKIT_BRIDGE_BUILD_EXAMPLES "Build the bridge examples" ON)
+
+if(LIVEKIT_BRIDGE_BUILD_EXAMPLES)
+  # ---- Set RPATH so examples find shared libs in the executable directory ----
+  if(UNIX)
+    if(APPLE)
+      set(CMAKE_BUILD_RPATH "@loader_path;@loader_path/../lib")
+      set(CMAKE_INSTALL_RPATH "@loader_path;@loader_path/../lib")
+    else()
+      set(CMAKE_BUILD_RPATH "$ORIGIN:$ORIGIN/../lib")
+      set(CMAKE_INSTALL_RPATH "$ORIGIN:$ORIGIN/../lib")
+    endif()
+    set(CMAKE_BUILD_RPATH_USE_ORIGIN TRUE)
+    set(CMAKE_SKIP_BUILD_RPATH FALSE)
+    set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
+  endif()
+
+  # ---- SDL3 (shared by robot and human targets) ----
+  list(APPEND CMAKE_MODULE_PATH "${LIVEKIT_ROOT_DIR}/examples/cmake")
+  include(sdl3)
+
+  # Path to the SDL media helpers in examples/simple_room/
+  set(SDL_MEDIA_DIR "${LIVEKIT_ROOT_DIR}/examples/simple_room")
+
+  # ---- Stub examples (no SDL, synthetic data) ----
+  add_executable(robot_stub examples/robot_stub.cpp)
+  target_link_libraries(robot_stub PRIVATE livekit_bridge)
+
+  add_executable(human_stub examples/human_stub.cpp)
+  target_link_libraries(human_stub PRIVATE livekit_bridge)
+
+  # ---- Robot: Real webcam + mic via SDL3 ----
+  add_executable(robot
+    examples/robot.cpp
+    ${SDL_MEDIA_DIR}/sdl_media.cpp
+    ${SDL_MEDIA_DIR}/sdl_media.h
+  )
+  target_include_directories(robot PRIVATE ${SDL_MEDIA_DIR})
+  target_link_libraries(robot PRIVATE livekit_bridge SDL3::SDL3)
+
+  # ---- Human: SDL3 video display + speaker playback ----
+  add_executable(human
+    examples/human.cpp
+    ${SDL_MEDIA_DIR}/sdl_media.cpp
+    ${SDL_MEDIA_DIR}/sdl_media.h
+  )
+  target_include_directories(human PRIVATE ${SDL_MEDIA_DIR})
+  target_link_libraries(human PRIVATE livekit_bridge SDL3::SDL3)
+
+  # ---- Copy SDL3 shared library to robot/human output directories, avoids duplicate code ----
+  set(_SDL_TARGETS robot human)
+  foreach(_target ${_SDL_TARGETS})
+    if(UNIX AND NOT APPLE)
+      add_custom_command(TARGET ${_target} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                "$<TARGET_FILE:SDL3::SDL3>"
+                "$<TARGET_FILE_DIR:${_target}>"
+        COMMAND ${CMAKE_COMMAND} -E create_symlink
+                "$<TARGET_FILE_NAME:SDL3::SDL3>"
+                "$<TARGET_FILE_DIR:${_target}>/$<TARGET_SONAME_FILE_NAME:SDL3::SDL3>"
+        COMMENT "Copying SDL3 shared library and SONAME symlink to ${_target} output directory"
+        VERBATIM
+      )
+    else()
+      add_custom_command(TARGET ${_target} POST_BUILD
+        COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                "$<TARGET_FILE:SDL3::SDL3>"
+                "$<TARGET_FILE_DIR:${_target}>"
+        COMMENT "Copying SDL3 shared library to ${_target} output directory"
+        VERBATIM
+      )
+    endif()
+  endforeach()
+endif()