Use GLFW3 all caps to avoid issues on Windows

[S-Dafarra]

Fixes: #1597

[traversaro]

Thanks!

A bit of background, FindGLFW3 needs to be capital here as there is https://github.com/robotology/ycm/blob/master/find-modules/FindGLFW3.cmake in YCM. My error was to follow official glfw3 docs (https://www.glfw.org/docs/3.3/build_guide.html#build_link_cmake_package), that instead refer to glfw3, as glfw3 itself ships a glfw3Config.cmake (see for example https://conda-metadata-app.streamlit.app/?q=conda-forge%2Fwin-64%2Fglfw-3.3.9-hcfcfb64_0.conda). To avoid further confusion like this, I would like to deprecate the FindGLFW3 in YCM, and instead use just the upstream glew3Config.cmake file. However, this would not work if we did find_package(GLFW3) here, as glew3Config.cmake will only be found by find_package(glfw3) calls, not find_package(GLFW3) calls (this is due to the fact that the file is named glfw3Config.cmake, if it was named glfw3-config.cmake any call to find_package(glfw3) , find_package(GLFW3) or find_package(GlFw3) would always find glfw3-config.cmake, see https://cmake.org/cmake/help/latest/command/find_package.html#search-modes).

So, to be future friendly, I would stick to find_package(glfw3), and just enable irrlicht if either glfw3_FOUND or GLFW3_FOUND are true, what do you think?

[traversaro]

By the way, interestingly we already worked on something related to this:

• FindGLFW3: Fix https://github.com/robotology/ycm/issues/133 ycm-cmake-modules#135
• Update FindGLFW3.cmake to support the latest version installed from vcpkg ycm-cmake-modules#133

[S-Dafarra]

Yeah it rang a bell also to me: ami-iit/yarp-device-openxrheadset@a1eeaed

Your solution sounds good!

[traversaro]

Superseded by #1599 .