* Fixed compile on OpenBSD

* Changed to not use seperate UNIX for cmake

* OpenGLES 2.0 support on PLATFORM_DESKTOP

* exmples raylib_opengl_interop desktop GLES2 support

* rename gles2.h -> glad_gles2.h

Use GLVND also when legacy implementations exist for old cmake versions
<= 3.10. This is a breaking change for old cmake versions (prior to
around 2017-10-05) which will now use GLVND rather than defaulting to
libGL.

This fixes the following warning when building:

    CMake Warning (dev) at /gnu/store/qv13zgbmyx0vjav8iiqp772kp6rxvwnd-cmake-3.24.2/share/cmake-3.24/Modules/FindOpenGL.cmake:315 (message):
      Policy CMP0072 is not set: FindOpenGL prefers GLVND by default when
      available.  Run "cmake --help-policy CMP0072" for policy details.  Use the
      cmake_policy command to set the policy and suppress this warning.

      FindOpenGL found both a legacy GL library:

        OPENGL_gl_LIBRARY: /home/simendsjo/.guix-profile/lib/libGL.so

      and GLVND libraries for OpenGL and GLX:

        OPENGL_opengl_LIBRARY: /home/simendsjo/.guix-profile/lib/libOpenGL.so
        OPENGL_glx_LIBRARY: /home/simendsjo/.guix-profile/lib/libGLX.so

      OpenGL_GL_PREFERENCE has not been set to "GLVND" or "LEGACY", so for
      compatibility with CMake 3.10 and below the legacy GL library will be used.
    Call Stack (most recent call first):
      cmake/LibraryConfigurations.cmake:21 (find_package)
      src/CMakeLists.txt:46 (include)
    This warning is for project developers.  Use -Wno-dev to suppress it.

See https://cmake.org/cmake/help/latest/policy/CMP0072.html

Closes #2825

Those functions were platform dependent and user has no control over the file created. They have been removed from raylib and just moved to `core_storage_values` example.

`android_native_app_glue.c` wasn't appended to the `raylib_sources` as other libraries were.

Co-authored-by: Patrick Martin <martinpatrick@google.com>

Updated cmake to windows users.
So they can `find_package(raylib [...])` with exported target as raylib instead of ${raylib_LIBRARIES}, etc

This fixes compilation and linking errors when CUSTOMIZE_BUILD is
ON. Any option wasn't actually applied if it wasn't in this list.

I also added a message which makes it a bit easier to confirm you have
successfully enabled an option.

* Fixed Compiling Raylib for android Using cmake

* improved the cmake config for android so it don't conflict

* improved the cmake config for android so it don't conflict

* Add find opengl for widnows too.

* Also fix set LIBS_PRIVATE to bi similar to linux and apple targets

* Log a warning if chdir failed, use agnostic CHDIR instead of chdir

* Only include libdrm directory explicitly when not cross compiling

* Update CMakeOptions.txt

* Update config.h.in

* Added SUPPORT_STANDARD_FILEIO to CMakeOptions.txt

* Fixed typo

* Added SUPPORT_STANDARD_FILEIO to CompileDefinitions.cmake

Co-authored-by: KirottuM <kirottum@protonmail.com>

* Documenting the compiler flags

* Moved some android compiler flags and added documentation on them too.

* Some more restructuring.

Removed unnecessary comments that were self described by the code.
Added some more explanations around certain parts of CMake and especially around compiler flags.

CMake relied on this file for configurations and also was interfering in the regular config.h by having a separate definition if building with CMake. This was not entirely correct so instead we will define compile time definitions separately through CMake (CompileDefinitions.cmake) and also will use the provided EXTERNAL_CONFIG_FLAGS that I found that will not use config.h in through the build process.

I also introduced a new compiler option (CUSTOMIZE_BUILD) that when OFF will use the default config.h and when ON will show other options for redefining your own options.

Fixed an error in rlgl.h where if you have both RLGL_STANDALONE and SUPPORT_VR_SIMULATOR you get a compile time error.

This test file is just testing compilation with the library works correctly but is no longer needed because:
- it is not cross platform
- it taps into the CTest system which is better suited for real unit/integration tests
- it can be incorporated into the pipeline of github actions instead in the future

As described in the official documentation https://cmake.org/cmake/help/v3.0/variable/BUILD_SHARED_LIBS.html this flag is global by default and controls if the library will be built as a shared or a static library allowing us to define only one call to the add_library function (without specifying its type). It is also added as an option to be visible in CMake GUI applications.

* Delete emscripten.cmake

This file is not needed at this point. EMSDK provides a toolchain file that has a lot more things in it and is better supported. Project currently works fine with the documentation provided in Emscripten SDK on how to build projects.

* First pass file separation.

The main two files are cleaner now. Only important things can be seen. Major changes include:
- raylib_static is now the alias instead of raylib
- Repeating segments are removed and pulled into separate files into <root>/cmake
- File is reordered to make more sense
- Installs are better structured
- Library is build into an output directory "raylib" instead of "src"
- All public header files are now set as a public header file
- Source files need to be listed (it is a bad practice to capture them using wildcards and file globs)
- CMakeLists are better commented

* Second pass on the example dirs.

They are quite complex so I'm more hesitant to do major changes. Also it works pretty well. Noticed that I forgot one of the seperated files and added it into src/CMakeLists.txt.

* Returned the header copy as it was convenient to have the public headers copied.

* A better description to the variable RAYLIB_IS_MAIN

Co-authored-by: Rob Loach <robloach@gmail.com>

* Remove debug message

Co-authored-by: Rob Loach <robloach@gmail.com>

* Improvements based on review.

* Simplify the install condition to not be platform specific as it was before.

Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

* Remove some CMAKE variables as they don't affect the build in any way

Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

Co-authored-by: Rob Loach <robloach@gmail.com>
Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

* Fixed the build for web using CMake.

I found that the build for me was failing and I added some if defined checks in the core.c file where the glfwSetWindowAttrib was used. (error: implicit declaration of function 'glfwSetWindowAttrib' is invalid in C99 [-Werror,-Wimplicit-function-declaration])

I also changed some values in the toolchain file so that it correctly uses the .bat files when on windows.

* Cleaned up the additional variables (they are not important)

* Added more improvements to cmakelists

Added the option to use the system provided Emscripten toolchain to be more uniform with other libraries.

Fixed and issue which prevented example being built from cmake and also building with html extensions properly.

* Fixed ENUM to STRING because of a missed warning

Fixes #1380: incorrect usage of CMake paths which causes issues
on some more complicated environments (NixOS especially).

As noted in #539, the symlink check was to support compiling raylib on
VirtualBox vboxfs as no symlinks are supported there.

With me using Linux as daily driver outside VirtualBox now, this 'feature'
is most likely unused by anyone, but still annoys other users (#791).
Just revert it and be done with it. If there are really others building
raylib on vboxfs or a similarly crippled file system under Linux, they
should now step forward when their build breaks.

This reverts commit b8ca51fd01.

Fixes #899, which made apparent three issues with how static libraries
are handled in raylib-config.cmake:

- XPREFIX is set before pkg_check_modules, which causes a duplicate
  STATIC in variables, e.g. PC_RAYLIB_STATIC_STATIC_.*
- raylib_static is searched for, but no library exists with that name
- raylib_LDFLAGS isn't populated properly

This commit fixes these.

Remove that link_libraries_to_executable() hack and defines a proper
raylib target that can be used with target_link_libraries.

The same target is also available for external (user) code by using
find_package(raylib).

This results in:

- Remove hardcoded build directories from examples and games CMakeLists.txt
- Allow rlgl_standalone and other special examples to be built easily
- Allow CMake projects to find_package(raylib instead of fiddling with pkg-config
- Makes code a little more maintainable
- Fixes #471, #606.
- Makes code less confusing by removing the double use of PLATFORM (#584).

Note that this is still not _The Right Way_(TM), because normally
raylib-config.cmake (or its includes) would be automatically generated.
I didn't manage to get that to work though, so I went the easier route
of just wrapping pkg_check_modules for consumption by find_package.

as well as -DUSE_EXTERNAL_GLFW.

Nips issues like #584 in the bud.

if (${PLATFORM} MATCHES "Desktop")
  target_link_libraries(${RAYLIB}_shared glfw ${GLFW_LIBRARIES})

was never true because PLATFORM STREQUAL "PLATFORM_DESKTOP"...

This fixes #551 and makes the changes suggested in #552 (commited as 965cc8ab)
unnecessary.

Temporary measure to fix a breakage on FreeBSD.
See #551 for more details.

Did this ever work? Surely, doesn't look like it...

Not sure if this ever worked, but now it at least compiles.

Release, unless we are in a Git repo, then it's Debug.