(Android) Added build support to the CMake configuration

CMake/Packages/FindOpenGLES3.cmake

@@ -0,0 +1,32 @@
+# FindOpenGLES
+# ------------
+# Finds the OpenGLES3 library
+#
+# This will define the following variables::
+#
+# OPENGLES3_FOUND - system has OpenGLES
+# OPENGLES3_INCLUDE_DIRS - the OpenGLES include directory
+# OPENGLES3_LIBRARIES - the OpenGLES libraries
+
+if(NOT HINT_GLES_LIBNAME)
+    set(HINT_GLES_LIBNAME GLESv3)
+endif()
+
+find_path(OPENGLES3_INCLUDE_DIR GLES3/gl3.h
+    PATHS "${CMAKE_FIND_ROOT_PATH}/usr/include"
+    HINTS ${HINT_GLES_INCDIR}
+)
+
+find_library(OPENGLES3_gl_LIBRARY
+    NAMES ${HINT_GLES_LIBNAME}
+    HINTS ${HINT_GLES_LIBDIR}
+)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(OpenGLES3 REQUIRED_VARS OPENGLES3_gl_LIBRARY OPENGLES3_INCLUDE_DIR)
+
+if(OPENGLES3_FOUND)
+    set(OPENGLES3_LIBRARIES ${OPENGLES3_gl_LIBRARY})
+    set(OPENGLES3_INCLUDE_DIRS ${OPENGLES3_INCLUDE_DIR})
+    mark_as_advanced(OPENGLES3_INCLUDE_DIR OPENGLES3_gl_LIBRARY)
+endif()

CMakeLists.txt

@@ -114,6 +114,8 @@ set_property(CACHE GLSYSTEM PROPERTY STRINGS "Desktop OpenGL" "Embedded OpenGL")
 if(GLSYSTEM MATCHES "Desktop OpenGL")
     set(OpenGL_GL_PREFERENCE GLVND)
     find_package(OpenGL REQUIRED)
+elseif(ANDROID)
+    find_package(OpenGLES3 REQUIRED)
 elseif(GLES AND NOT EMSCRIPTEN)
     find_package(OpenGLES2 REQUIRED)
 endif()
@@ -129,7 +131,7 @@ elseif(WIN32)
        NOT EXISTS ${PROJECT_SOURCE_DIR}/external/pugixml/pugixml.dll)       # MSVC
         message(FATAL_ERROR "-- You need to build the dependencies in ./external first")
     endif()
-elseif(NOT EMSCRIPTEN)
+elseif(NOT EMSCRIPTEN AND NOT ANDROID)
     find_package(CURL REQUIRED)
     find_package(FFmpeg REQUIRED)
     find_package(FreeImage REQUIRED)
@@ -218,6 +220,10 @@ if(APPLE AND CMAKE_CXX_COMPILER_VERSION GREATER_EQUAL 15.0.0)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-invalid-utf8")
 endif()
 
+if(ANDROID)
+    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -llog")
+endif()
+
 if(EMSCRIPTEN)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -s USE_SDL=2 -pthread")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -s INITIAL_MEMORY=33554432 -s ALLOW_MEMORY_GROWTH=1 -s WASM=1 -s ASSERTIONS=1 -s EXIT_RUNTIME=1 -s USE_SDL=2 \
@@ -379,6 +385,18 @@ if(APPLE)
     endif()
 endif()
 
+if(ANDROID)
+    if(ANDROID_ABI MATCHES arm64-v8a)
+        message("-- Building for Android arm64-v8a")
+        set(ANDROID_CPU_ARCH arm64-v8a)
+    elseif(ANDROID_ABI MATCHES x86_64)
+        message("-- Building for Android x86_64")
+        set(ANDROID_CPU_ARCH x86_64)
+    else()
+        message(FATAL_ERROR "-- Unsupported Android ABI: " ${ANDROID_ABI})
+    endif()
+endif()
+
 # Affects the application updater and is used for displaying version info in the main menu.
 if(ES_VERSION MATCHES alpha OR ES_VERSION MATCHES beta OR ES_VERSION MATCHES dev)
     add_compile_definitions(IS_PRERELEASE)
@@ -446,6 +464,15 @@ elseif(EMSCRIPTEN)
                             ${CMAKE_CURRENT_SOURCE_DIR}/external/FreeImage-CMake/FreeImage/Source
                             ${CMAKE_CURRENT_SOURCE_DIR}/external/freetype/include
                             ${CMAKE_CURRENT_SOURCE_DIR}/external/pugixml/src)
+elseif(ANDROID)
+    set(COMMON_INCLUDE_DIRS ${COMMON_INCLUDE_DIRS}
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/curl/include
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/ffmpeg-kit/src/ffmpeg
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/freeimage/FreeImage/Source
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/freetype/include
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/libgit2/include
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/pugixml/src
+                            ${CMAKE_CURRENT_SOURCE_DIR}/external/SDL_Android)
 else()
     set(COMMON_INCLUDE_DIRS ${COMMON_INCLUDE_DIRS}
                             ${FFMPEG_INCLUDE_DIRS}
@@ -529,6 +556,22 @@ elseif(WIN32)
                              mingw32
                              Winmm.dll)
     endif()
+elseif(ANDROID)
+    set(COMMON_LIBRARIES ${COMMON_LIBRARIES}
+                        # FFmpeg libraries.
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libavcodec.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libavfilter.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libavformat.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libavutil.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libswresample.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libswscale.so
+                        # Other dependencies.
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libcurl.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libfreeimage.a
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libfreetype.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libgit2.so
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libpugixml.a
+                        ${PROJECT_SOURCE_DIR}/android/libs/${ANDROID_CPU_ARCH}/libSDL2.so)
 elseif(EMSCRIPTEN)
     set(COMMON_LIBRARIES ${COMMON_LIBRARIES}
                          # FFmpeg core libraries.
@@ -611,6 +654,8 @@ endif()
 # OpenGL.
 if(GLSYSTEM MATCHES "Desktop OpenGL")
     list(APPEND COMMON_LIBRARIES ${OPENGL_LIBRARIES})
+elseif(GLES AND ANDROID)
+    list(APPEND COMMON_LIBRARIES ${OPENGLES3_LIBRARIES})
 elseif(GLES)
     list(APPEND COMMON_LIBRARIES ${OPENGLES2_LIBRARIES})
 endif()
@@ -623,13 +668,18 @@ set(EXECUTABLE_OUTPUT_PATH ${dir} CACHE PATH "Build directory" FORCE)
 set(LIBRARY_OUTPUT_PATH ${dir} CACHE PATH "Build directory" FORCE)
 
 # Add each component.
+if(NOT ANDROID)
     add_subdirectory(es-pdf-converter)
+endif()
 add_subdirectory(external)
 add_subdirectory(es-core)
 add_subdirectory(es-app)
 
+if(NOT ANDROID)
     # Make sure that es-pdf-convert is built first, and then that rlottie is built before es-core.
     # Also set lottie2gif to not be built.
     add_dependencies(lunasvg es-pdf-convert)
+endif()
+
 add_dependencies(es-core rlottie)
 set_target_properties(lottie2gif PROPERTIES EXCLUDE_FROM_ALL 1 EXCLUDE_FROM_DEFAULT_BUILD 1)

es-app/CMakeLists.txt

@@ -132,6 +132,11 @@ elseif(WIN32)
     add_executable(EmulationStation WIN32 ${ES_SOURCES} ${ES_HEADERS})
     target_link_libraries(EmulationStation ${COMMON_LIBRARIES} es-core)
     set_target_properties(EmulationStation PROPERTIES INSTALL_RPATH_USE_LINK_PATH TRUE)
+elseif(ANDROID)
+    include_directories(${COMMON_INCLUDE_DIRS} ${CMAKE_CURRENT_SOURCE_DIR}/src)
+    add_library(main SHARED ${ES_SOURCES} ${ES_HEADERS})
+    target_link_libraries(main ${COMMON_LIBRARIES} ${CMAKE_DL_LIBS} es-core)
+    set_target_properties(main PROPERTIES INSTALL_RPATH_USE_LINK_PATH TRUE)
 else()
     include_directories(${COMMON_INCLUDE_DIRS} ${CMAKE_CURRENT_SOURCE_DIR}/src)
     add_executable(emulationstation ${ES_SOURCES} ${ES_HEADERS})
@@ -325,7 +330,7 @@ elseif(APPLE)
     install(DIRECTORY ${CMAKE_SOURCE_DIR}/themes/modern-es-de DESTINATION ../Resources/themes)
     install(DIRECTORY ${CMAKE_SOURCE_DIR}/themes/slate-es-de DESTINATION ../Resources/themes)
     install(DIRECTORY ${CMAKE_SOURCE_DIR}/licenses DESTINATION ../Resources)
-else()
+elseif(NOT ANDROID)
     install(TARGETS emulationstation RUNTIME DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
     install(TARGETS es-pdf-convert RUNTIME DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
     if(CMAKE_SYSTEM_NAME MATCHES Linux)