MSYS2 + MinGW-w64 上 CMake 找不到 SDL2_ttf 库怎么办？

2024-03-11 10:21:38

## 在 MSYS2 + MinGW-w64 上使用 CMake 查找 SDL2_ttf 库的指南

问题概述

在 Windows 下使用 MinGW 编译 SDL2 项目时，CMake 可能无法找到 SDL2_ttf 库。这会导致以下错误消息：

CMake Error at CMakeLists.txt:14 (find_package):
  By not providing "FindSDL2_ttf.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "SDL2_ttf",
  but CMake did not find one.

  Could not find a package configuration file provided by "SDL2_ttf" with any
  of the following names:

    SDL2_ttfConfig.cmake
    sdl2_ttf-config.cmake

  Add the installation prefix of "SDL2_ttf" to CMAKE_PREFIX_PATH or set
  "SDL2_ttf_DIR" to a directory containing one of the above files.  If
  "SDL2_ttf" provides a separate development package or SDK, be sure it has
  been installed.

解决步骤

1. 验证安装

首先，确保已经安装了 mingw-w64-x86_64-SDL2 和 mingw-w64-x86_64-SDL2_ttf 软件包。

2. 检查 CMake 配置

接下来，验证 CMake 配置文件 /mingw64/lib/cmake/SDL2_ttf/sdl2_ttf-config.cmake 是否已正确安装。

3. 更新 CMakeLists.txt

要解决此问题，需要在 CMakeLists.txt 中设置 SDL2_ttf_DIR，使其指向 SDL2_ttf CMake 配置文件所在的目录：

set(SDL2_ttf_DIR "/mingw64/lib/cmake/SDL2_ttf")

或者，也可以将 SDL2_ttf 的安装目录添加到 CMAKE_PREFIX_PATH 中：

set(CMAKE_PREFIX_PATH "/mingw64/lib/cmake/SDL2_ttf")

4. 重新运行 CMake

更新 CMakeLists.txt 后，重新运行 CMake 以生成项目文件。

示例 CMakeLists.txt

以下是一个示例 CMakeLists.txt，展示了如何设置 SDL2_ttf_DIR：

cmake_minimum_required(VERSION 3.16)
project(project VERSION 0.0.1)

file(GLOB SOURCE_FILES
    src/[a-z]*.c
)

set(CMAKE_C_STANDARD 99)
set(CMAKE_C_STANDARD_REQUIRED YES)
set(CMAKE_C_EXTENSIONS OFF)

set(SDL2_ttf_DIR "/mingw64/lib/cmake/SDL2_ttf")
find_package(SDL2 REQUIRED)
find_package(SDL2_ttf REQUIRED)

set(C_FLAGS "-rdynamic")

set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${C_FLAGS}")

ADD_EXECUTABLE(${PROJECT_NAME} ${SOURCE_FILES})
TARGET_LINK_LIBRARIES(${PROJECT_NAME}
                      SDL2::SDL2
                      SDL2_ttf
)