Merge branch 'FindOpenGL-glvnd-preference' into release-3.10

Merge-request: !1485
This commit is contained in:
Brad King 2017-11-15 13:46:05 -05:00
commit 47c2baf06a

View File

@ -84,12 +84,26 @@
# ``OpenGL::GLX`` or ``OpenGL::EGL``.
#
# Projects may use the ``OpenGL::GL`` target (or ``OPENGL_LIBRARIES`` variable)
# to use legacy GL. By default, these will use the legacy libGL library file.
# If ``OPENGL_gl_LIBRARY`` is empty or not found and GLVND is available, the
# ``OpenGL::GL`` target will use GLVND ``OpenGL::OpenGL`` and ``OpenGL::GLX``
# (and the ``OPENGL_LIBRARIES`` variable will use the corresponding libraries).
# Thus, for non-EGL-based Linux targets, the ``OpenGL::GL`` target is most
# portable.
# to use legacy GL interfaces. These will use the legacy GL library located
# by ``OPENGL_gl_LIBRARY``, if available. If ``OPENGL_gl_LIBRARY`` is empty or
# not found and GLVND is available, the ``OpenGL::GL`` target will use GLVND
# ``OpenGL::OpenGL`` and ``OpenGL::GLX`` (and the ``OPENGL_LIBRARIES``
# variable will use the corresponding libraries). Thus, for non-EGL-based
# Linux targets, the ``OpenGL::GL`` target is most portable.
#
# A ``OpenGL_GL_PREFERENCE`` variable may be set to specify the preferred way
# to provide legacy GL interfaces in case multiple choices are available.
# The value may be one of:
#
# ``GLVND``
# If the GLVND OpenGL and GLX libraries are available, prefer them.
# This forces ``OPENGL_gl_LIBRARY`` to be empty.
# This is the default if components were requested (since components
# correspond to GLVND libraries).
#
# ``LEGACY``
# Prefer to use the legacy libGL library, if available.
# This is the default if no components were requested.
#
# For EGL targets the client must rely on GLVND support on the user's system.
# Linking should use the ``OpenGL::OpenGL OpenGL::EGL`` targets. Using GLES*
@ -179,13 +193,6 @@ else()
/opt/graphics/OpenGL/include /usr/X11R6/include
)
find_library(OPENGL_gl_LIBRARY
NAMES GL MesaGL
PATHS /opt/graphics/OpenGL/lib
/usr/openwin/lib
/usr/shlib /usr/X11R6/lib
${_OPENGL_LIB_PATH}
)
# Search for the GLVND libraries. We do this regardless of COMPONENTS; we'll
# take into account the COMPONENTS logic later.
find_library(OPENGL_opengl_LIBRARY
@ -213,6 +220,43 @@ else()
/usr/shlib /usr/X11R6/lib
)
if(NOT DEFINED OpenGL_GL_PREFERENCE)
set(OpenGL_GL_PREFERENCE "")
endif()
if(NOT OpenGL_GL_PREFERENCE STREQUAL "")
# A preference has been explicitly specified.
if(NOT OpenGL_GL_PREFERENCE MATCHES "^(GLVND|LEGACY)$")
message(FATAL_ERROR
"OpenGL_GL_PREFERENCE value '${OpenGL_GL_PREFERENCE}' not recognized. "
"Allowed values are 'GLVND' and 'LEGACY'."
)
endif()
elseif(OpenGL_FIND_COMPONENTS)
# No preference was explicitly specified, but the caller did request
# at least one GLVND component. Prefer GLVND for legacy GL.
set(OpenGL_GL_PREFERENCE "GLVND")
else()
# No preference was explicitly specified and no GLVND components were
# requested. Prefer libGL for legacy GL.
set(OpenGL_GL_PREFERENCE "LEGACY")
endif()
if("x${OpenGL_GL_PREFERENCE}x" STREQUAL "xGLVNDx" AND OPENGL_opengl_LIBRARY AND OPENGL_glx_LIBRARY)
# We can provide legacy GL using GLVND libraries.
# Do not use any legacy GL library.
set(OPENGL_gl_LIBRARY "")
else()
# We cannot provide legacy GL using GLVND libraries.
# Search for the legacy GL library.
find_library(OPENGL_gl_LIBRARY
NAMES GL MesaGL
PATHS /opt/graphics/OpenGL/lib
/usr/openwin/lib
/usr/shlib /usr/X11R6/lib
${_OPENGL_LIB_PATH}
)
endif()
# FPHSA cannot handle "this OR that is required", so we conditionally set what
# it must look for. First clear any previous config we might have done:
set(_OpenGL_REQUIRED_VARS)