Switch to Doxygen

clang-doc is nice and good, but there are features missing such as the ability to manually create a reference (link)...

.github/workflows/rust.yaml

@@ -80,8 +80,8 @@ jobs:
       with:
           command: test
           args: --verbose
-    - name: Install clang-doc
-      run: sudo apt-get install clang-tools-10 clang-10-doc
+    - name: Install doxygen
+      run: sudo apt-get install doxygen
     - name: Prepare cmake module
       run: cargo xtask cmake --prefix $HOME/sixtyfps_install --install
     - name: C++ Test
@@ -121,7 +121,7 @@ jobs:
           rm -rf docs
           mkdir -p docs
           mkdir -p docs/cpp
-          cp -a ../target/debug/docs/* docs/cpp/
+          cp -a ../target/debug/docs/html/* docs/cpp/
           git add docs
           git add -u docs
           git commit --message "Update $NAME from $GITHUB_REPOSITORY" --message "Pull web demos and C++ reference docs from commit $GITHUB_SHA ($GITHUB_REF)"

api/sixtyfps-cpp/cmake/CMakeLists.txt

@@ -83,20 +83,8 @@ install(FILES
     DESTINATION lib/cmake/SixtyFPS
 )
 
-if(APPLE)
-    execute_process(COMMAND brew --prefix llvm RESULT_VARIABLE prefix_status OUTPUT_VARIABLE llvm_prefix ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
-    if(prefix_status EQUAL "0")
-        set(clang_doc_hint "HINTS;${llvm_prefix}/bin")
-    endif()
-endif()
-
-find_program(clang_doc NAMES clang-doc clang-doc-10 ${clang_doc_hint})
-if(clang_doc)
-    message(STATUS "Clang doc found at ${clang_doc}. Will build API documentation")
-    add_library(api_docs lib.cpp)
-    target_link_libraries(api_docs SixtyFPS)
-    add_custom_target(docs ALL COMMAND ${clang_doc} -p ${CMAKE_CURRENT_BINARY_DIR} --format=html --public --project-name "SixtyFPS C++" ${CMAKE_CURRENT_SOURCE_DIR}/lib.cpp)
-else()
-    message(STATUS "Clang doc NOT found. Will NOT build API documentation")
-    add_custom_target(docs COMMAND ${CMAKE} -E echo "Not building documentation because clang-doc wasn't found in PATH")
+find_package(Doxygen)
+if (DOXYGEN_FOUND)
+    configure_file(Doxyfile.in Doxyfile)
+    add_custom_target(docs ALL COMMAND ${DOXYGEN_EXECUTABLE} ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile)
 endif()