• Jon Turney's avatar
    configure: Look for Khronos OpenGL spec files using pkg-config · a5087868
    Jon Turney authored
    
    
    Look for Khronos OpenGL spec files using pkg-config, rather than downloading them
    
    Also add a --with-khronos-spec-dir=PATH configure option so XWin can be directed
    where to find these files without using the khronos-spec-files package
    
    XWin with AIGLX requires OpenGL spec files in order to generate wrapper code which:
    (1) thunks from the glapi dispatch table which uses the default cdecl calling convention
    to native GL functions using the stdcall calling convention.
    (2) performs function address lookup for OpenGL 1.2+ functions, which are treated
    as extensions and so not directly linkable.
    
    v2: KHRONOS_SPEC_DIR is only valid when XWIN_GLX_WINDOWS is defined. Avoid 'make dist'
    seeing invalid dependencies by only including rules using KHRONOS_SPEC_DIR if
    XWIN_GLX_WINDOWS is defined
    
    Signed-off-by: Jon Turney's avatarJon TURNEY <jon.turney@dronecode.org.uk>
    Reviewed-by: default avatarColin Harrison <colin.harrison@virgin.net>
    Reviewed-by: default avatarIan Romanick <ian.d.romanick@intel.com>
    a5087868