将SDL2_net与CMake链接

Question

我正在尝试通过CMake将SDL2_net（SDL_net 2.0）链接到我的项目，但在搜索之后我还没有找到解决方案。我的CMakeLists.txt目前看起来像这样：

1 cmake_minimum_required (VERSION 3.7)
2 project (SDL_net_test)
3 include (FindPkgConfig)
4 include (FindSDL_net)
5 
6 pkg_search_module (SDL2 REQUIRED sdl2)
7 pkg_search_module (SDL_NET REQUIRED sdl2_net)
8 
9 include_directories (${SDL2_INCLUDE_DIRS} ${SDL_NET_INCLUDE_DIRS})
10 
11 add_executable (SDL_net_test main.cpp)
12 target_link_libraries (SDL_net_test ${SDL2_LIBRARIES} ${SDL_NET_LIBRARIES})

但是，当我尝试运行CMake时，它会给我以下错误：

-- Could NOT find SDL_net (missing: SDL_NET_LIBRARIES SDL_NET_INCLUDE_DIRS) 
-- Checking for one of the modules 'sdl2_net'
CMake Error at /usr/share/cmake/Modules/FindPkgConfig.cmake:659 (message):
None of the required 'sdl2_net' found
Call Stack (most recent call first):
CMakeLists.txt:7 (pkg_search_module)


CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
SDL_NET_INCLUDE_DIR (ADVANCED)
   used as include directory in directory /home/neboula/Programming/sandbox/sdl2_net
   used as include directory in directory /home/neboula/Programming/sandbox/sdl2_net
   used as include directory in directory /home/neboula/Programming/sandbox/sdl2_net
SDL_NET_LIBRARY (ADVANCED)
    linked by target "SDL_net_test" in directory /home/neboula/Programming/sandbox/sdl2_net

-- Configuring incomplete, errors occurred!
See also "/home/neboula/Programming/sandbox/sdl2_net/build/CMakeFiles/CMakeOutput.log".

我已经从我的软件包管理器（Fedora 29上的dnf）安装了SDL2_net-devel软件包，并且我已经成功地将SDL2和SDL2_image链接在以前基于this answer的基础上，后者运行得非常出色。我也找到了this，但我不完全确定如何使用它。我该怎么办呢？

Answer 1

由于提供答案的人只发表了评论，我自己就把它放在这里。

解决方案似乎非常简单：我写过pkg_search_module (SDL_NET REQUIRED sdl2_net)，而它应该是pkg_search_module (SDL_NET REQUIRED SDL2_net)。

Answer 2

为了轻松集成SDL2库和其他相关库（SDL2_net，SDL2_mixer，...），我开发了modern cross-platform CMake modules，可以按如下方式使用：

1. 在我们的项目中克隆SDL2 CMake模块：

git clone https://github.com/aminosbh/sdl2-cmake-modules cmake/sdl2

2. 在主CMakeLists.txt中添加以下行

list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake/sdl2)
find_package(SDL2 REQUIRED)
find_package(SDL2_net REQUIRED)
target_link_libraries(${PROJECT_NAME} SDL2::Main SDL2:Net)

您甚至可以指定自定义路径来查找SDL2，SDL2_net，...在Windows上特别有用。

cmake .. -DSDL2_PATH="/path/to/sdl2" -DSDL2_NET_PATH="/path/to/sdl2-net"

当然，您不应该忘记安装特定的包：

# Fedora/RPM
sudo yum install SDL2-devel SDL2_net-devel

# Debian/Ubuntu
sudo apt install libsdl2-dev libsdl2-net-dev