FindModule for OpenGL and OpenGL Utility Library (GLU).
This module respects several optional COMPONENTS: EGL
, GLX
, and OpenGL
. There are corresponding import targets for each of these flags.
This module defines the IMPORTED
targets:
OpenGL::GL
OpenGL::OpenGL
OpenGL::GLU
OpenGL::GLX
OpenGL::EGL
This module sets the following variables:
OPENGL_FOUND
OPENGL_XMESA_FOUND
OPENGL_GLU_FOUND
OpenGL_OpenGL_FOUND
OpenGL_GLX_FOUND
OpenGL_EGL_FOUND
OPENGL_INCLUDE_DIR
OPENGL_EGL_INCLUDE_DIRS
OPENGL_LIBRARIES
OpenGL::*
import targets instead.The following cache variables may also be set:
OPENGL_egl_LIBRARY
OPENGL_glu_LIBRARY
OPENGL_glx_LIBRARY
OPENGL_opengl_LIBRARY
OPENGL_gl_LIBRARY
OpenGL::*
import targets.Some Linux systems utilize GLVND as a new ABI for OpenGL. GLVND separates context libraries from OpenGL itself; OpenGL lives in “libOpenGL”, and contexts are defined in “libGLX” or “libEGL”. GLVND is currently the only way to get OpenGL 3+ functionality via EGL in a manner portable across vendors. Projects may use GLVND explicitly with target OpenGL::OpenGL
and either OpenGL::GLX
or OpenGL::EGL
.
Projects may use the OpenGL::GL
target (or OPENGL_LIBRARIES
variable) 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
OPENGL_gl_LIBRARY
to be empty. This is the default if components were requested (since components correspond to GLVND libraries) or if policy CMP0072
is set to NEW
.LEGACY
CMP0072
is not set to NEW
.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* libraries is theoretically possible in place of OpenGL::OpenGL
, but this module does not currently support that; contributions welcome.
OPENGL_egl_LIBRARY
and OPENGL_EGL_INCLUDE_DIRS
are defined in the case of GLVND. For non-GLVND Linux and other systems these are left undefined.
On OSX FindOpenGL defaults to using the framework version of OpenGL. People will have to change the cache values of OPENGL_glu_LIBRARY and OPENGL_gl_LIBRARY to use OpenGL with X11 on OSX.
© 2000–2019 Kitware, Inc. and Contributors
Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.15/module/FindOpenGL.html