在Ubuntu上,当我试图查找OpenGL时,CMake给了我令人困惑的结果。
背景是,我需要在服务器/ docker上进行无头渲染,而不需要X显示。我通过apt-get install libgl1-mesa-dev
和apt-get install libegl1-mesa-dev
安装了OpenGL。
以下是我CMakeLists.txt中相关部分:
cmake_minimum_required (VERSION 3.5.1)
project (sandbox LANGUAGES CXX)
# add OpenGL
find_package(OpenGL REQUIRED COMPONENTS OpenGL EGL GLX)
include_directories(${OPENGL_INCLUDE_DIRS})
if(OPENGL_FOUND)
message("Found OpenGL in the current environment!")
else()
message("Error: No OpenGL found.")
endif()
message("OpenGL include dirs" )
message("${OPENGL_INCLUDE_DIR}")
message("EGL include dirs" )
message("${OPENGL_EGL_INCLUDE_DIRS}")
if (OpenGL_EGL_FOUND)
message("EGL Found!")
else()
message("EGL Not Found!")
endif()
add_executable (sandbox "hello_egl.cpp" "shader.cpp")
target_link_libraries(sandbox PRIVATE OpenGL::OpenGL OpenGL::EGL OpenGL::GLX)
#target_include_directories(sandbox PRIVATE "/usr/include/EGL")
#target_link_libraries(sandbox "/usr/local/lib/x86_64-linux-gnu/libEGL.so")
#target_link_libraries(sandbox "/usr/local/lib/libEGL.so")
set_target_properties(sandbox PROPERTIES CXX_STANDARD 11)
我运行cmake ..
时出现以下错误:
Found OpenGL in the current environment!
OpenGL include dirs
/usr/local/include
EGL include dirs
EGL Not Found!
-- Configuring done
CMake Error at CMakeLists.txt:44 (add_executable):
Target "sandbox" links to target "OpenGL::OpenGL" but the target was not
found. Perhaps a find_package() call is missing for an IMPORTED target, or
an ALIAS target is missing?
CMake Error at CMakeLists.txt:44 (add_executable):
Target "sandbox" links to target "OpenGL::EGL" but the target was not
found. Perhaps a find_package() call is missing for an IMPORTED target, or
an ALIAS target is missing?
CMake Error at CMakeLists.txt:44 (add_executable):
Target "sandbox" links to target "OpenGL::GLX" but the target was not
found. Perhaps a find_package() call is missing for an IMPORTED target, or
an ALIAS target is missing?
很令人困惑的是,
CMake
将 OPENGL_FOUND
设置为 true
,但却无法链接到 OpenGL::OpenGL
目标?此外,我将 EGL
放在了 /usr/local/lib/x86_64-linux-gnu/
中,为什么 CMake 找不到它呢?root@6442439c7090:/app/sandbox/build# ls /usr/local/lib/x86_64-linux-gnu/
libEGL.so libGL.so.1 libGLESv1_CM.so.1.2.0 libGLX.so libGLdispatch.so.0 libOpenGL.so.0.0.0
libEGL.so.1 libGL.so.1.7.0 libGLESv2.so libGLX.so.0 libGLdispatch.so.0.0.0 pkgconfig
libEGL.so.1.1.0 libGLESv1_CM.so libGLESv2.so.2 libGLX.so.0.0.0 libOpenGL.so
libGL.so libGLESv1_CM.so.1 libGLESv2.so.2.1.0 libGLdispatch.so libOpenGL.so.0
我坚持使用
find_package
的原因是之前我手动链接到了libEGL.so
,但是在运行时应用程序无法获取显示屏。因此,我怀疑我链接了错误的库。terminate called after throwing an instance of 'std::runtime_error'
what(): EGL error 0x300c at eglGetDisplay
Aborted (core dumped)
cmake -DOPENGL_egl_LIBRARY=/usr/local/lib/x86_64-linux-gnu/libEGL.so ..
另外,你是否阅读了CMake文档中关于这个包的“Linux-specific”讨论?链接 - Kevincmake_minimum_required
要求),FindOpenGL.cmake模块无法找到EGL库,也无法处理COMPONENTS
部分。 - Tsyvarev