GDExample with CMake hot-reload

GDExtension C++ example using CMake with hot reloading enabled.

Instruction

1. Clone repository and enter it.

git clone https://github.com/Drahiri/gde_example_cmake_reload.git
cd gde_example_cmake_reload

2. Initialize godot-cpp submodule.

cd godot-cpp
git submodule update --init

3. Add following lines to godot-cpp/CMakeLists.txt at line 129 to match this PR.

if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
    set(GODOT_COMPILE_FLAGS "${GODOT_COMPILE_FLAGS} -fno-gnu-unique")
endif()

4. Leave godot-cpp folder.

cd ..

5. Create build folder, configure and build project. x is number of jobs.

mkdir build
cd build
cmake .. -GNinja
ninja -jx

6. Import and open demo project in Godot.

7. Make changes in gdexample.cpp file. Commenting out _bind_methods() content is good idea.

8. Rebuild library.

9. If you commented out _bind_methods() content, in editors' Inspector property Amplitude should disappear.