CMAKE: allow to use system wide installation of flatbuffers

.github/workflows/main.yml

@@ -61,7 +61,7 @@ jobs:
         - name: Setup
           run: |
             sudo apt-get update
-            sudo apt-get install cmake debhelper devscripts build-essential lintian libsdl2-dev libuv1-dev libsdl2-mixer-dev postgresql-server-dev-all libpq-dev libenet-dev opencl-c-headers wayland-protocols pkg-config uuid-dev python3
+            sudo apt-get install cmake debhelper devscripts build-essential lintian libsdl2-dev libuv1-dev libsdl2-mixer-dev postgresql-server-dev-all libpq-dev libenet-dev opencl-c-headers wayland-protocols pkg-config uuid-dev python3 flatbuffers-compiler
 
         - name: Ubuntu
           run: |
@@ -107,7 +107,7 @@ jobs:
         - name: Setup
           run: |
             sudo apt-get update
-            sudo apt-get install libsdl2-dev postgresql-server-dev-all libpq-dev libenet-dev opencl-c-headers wayland-protocols pkg-config uuid-dev ninja-build python3
+            sudo apt-get install libsdl2-dev postgresql-server-dev-all libpq-dev libenet-dev opencl-c-headers wayland-protocols pkg-config uuid-dev ninja-build python3 flatbuffers-compiler
 
         - name: Linux
           run: |

cmake/Findflatbuffers.cmake

@@ -1,2 +1,2 @@
 include("${ROOT_DIR}/cmake/macros.cmake")
-engine_find_header_only(flatbuffers flatbuffers.h "" "" "")
+engine_find_header_only(flatbuffers flatbuffers.h flatbuffers "")

cmake/Findglm.cmake

@@ -1,3 +1,3 @@
 #We need 0.9.8
 include("${ROOT_DIR}/cmake/macros.cmake")
-engine_find_header_only(glm detail/type_mat.hpp glm "" "")
+engine_find_header_only(glm detail/type_mat.hpp glm "")

contrib/libs/flatbuffers/CMakeLists.txt

@@ -14,7 +14,13 @@ engine_add_library(
 if (NOT FLATBUFFERS_FOUND)
 	target_include_directories(flatbuffers PUBLIC .)
 endif()
-set(COMPILER_SRCS
+
+find_program(FLATC_EXECUTABLE NAMES flatc)
+if (FLATC_EXECUTABLE)
+	add_executable(flatc IMPORTED GLOBAL)
+	set_property(TARGET flatc PROPERTY IMPORTED_LOCATION ${FLATC_EXECUTABLE})
+else()
+	set(COMPILER_SRCS
 		compiler/src/compiler/cpp_generator.cc
 		compiler/src/compiler/cpp_generator.h
 		compiler/src/compiler/go_generator.cc
@@ -51,8 +57,9 @@ set(COMPILER_SRCS
 		compiler/idl_parser.cpp
 		compiler/reflection.cpp
 		compiler/util.cpp
-)
-engine_add_build_executable(TARGET flatc SRCS ${COMPILER_SRCS} NOINSTALL)
-set_target_properties(flatc PROPERTIES UNITY_BUILD FALSE)
-target_link_libraries(flatc flatbuffers)
-target_include_directories(flatc PRIVATE compiler/)
+	)
+	engine_add_build_executable(TARGET flatc SRCS ${COMPILER_SRCS} NOINSTALL)
+	set_target_properties(flatc PROPERTIES UNITY_BUILD FALSE)
+	target_link_libraries(flatc flatbuffers)
+	target_include_directories(flatc PRIVATE compiler/)
+endif()

debian/control

@@ -14,6 +14,7 @@ Build-Depends:
  wayland-protocols,
  pkg-config,
  uuid-dev,
+ libflatbuffers-dev,
  libsdl2-mixer-dev
 Standards-Version: 4.1.4
 Homepage: https://github.com/mgerhardy/vengi