c++ fatal error: glad/gl.h: No such file or directory

Question

I want to make a simple game using C++ & GLFW.

I included the library using CMake as follows:

cmake_minimum_required(VERSION 3.15.3)

set(CMAKE_CXX_STANDART 20)

project(tetris_game)

SET(CMAKE_INCLUDE_CURRENT_DIR ON)

find_package(PkgConfig)

pkg_check_modules(opengl REQUIRED gl)

add_subdirectory(${PROJECT_SOURCE_DIR}/libs/glfw3)

add_executable(tetris ./src/main.cpp)

target_link_libraries(tetris ${opengl_LIBRARIES} glfw)
target_include_directories(tetris PUBLIC ${opengl_INCLUDE_DIRS})
target_compile_options(tetris PUBLIC ${opengl_CFLAGS_OTHER})

Without the glad/gl.h header file, OpenGL works fine. I successfully open a window using OpenGL, but when I include that header, the error occurs:

fatal error: glad/gl.h: No such file or directory

My directory structure as follows:

.
├── CMakeLists.txt
├── builds
├   ├── more files.
├
├-- libs
├   ├-- glfw3
├   ├   ├-- deps
├   ├   ├   ├-- glad
├   ├   ├   ├   ├-- gl.h
├   ├   ├   ├
├   ├   ├   ├-- glad_gl.c

...

I tried this solution:

instead of

add_executable(tetris ./src/main.cpp)

I use

add_executable(tetris ./src/main.cpp ${PROJECT_SOURCE_DIR}/libs/glfw3/deps/glad/gl.h ${PROJECT_SOURCE_DIR}/libs/glfw3/deps/glad_gl.c)

but did not work.

Answer 1

I just added this two lines to CMakeLists.txt

include_directories(${PROJECT_SOURCE_DIR}/libs/glfw3/deps/)
add_executable(tetris ./src/main.cpp ${PROJECT_SOURCE_DIR}/libs/glfw3/deps/glad_gl.c)

Now, OpenGL is working.