问题遇到的现象和发生背景
问题相关代码，请勿粘贴截图
运行结果及报错内容
CMake Error at /usr/share/cmake-3.10/Modules/FindPackageHandleStandardArgs.cmake:137 (message):
Could NOT find SDL (missing: SDL_LIBRARY SDL_INCLUDE_DIR)
Call Stack (most recent call first):
/usr/share/cmake-3.10/Modules/FindPackageHandleStandardArgs.cmake:378 (_FPHSA_FAILURE_MESSAGE)
/usr/share/cmake-3.10/Modules/FindSDL.cmake:190 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
navigation-melodic/map_server/CMakeLists.txt:12 (find_package)
-- Configuring incomplete, errors occurred!
See also "/home/xwc/catkin_ws/build/CMakeFiles/CMakeOutput.log".
See also "/home/xwc/catkin_ws/build/CMakeFilelog".
Invoking "cmake" failed
