How To Properly Include SDL2 Source Code in Project CMake - c++

I am confused on how to statically include the source code of SDL2. I am trying to do this to make a library I am working on more portable.
Currently, when I try to include my library in another project it says "Cannot open include file: 'SDL2/SDL.h': No such file or directory".
My Filesystem:
include
--Header Files
src
--Source Files
extern
--SDL2
build
Here is an example of the file causing the error:
#include <iostream>
#include <SDL2/SDL.h> //Error
using namespace std;
/* The code */
Here is an example of my main CMakeLists.txt:
cmake_minimum_required(VERSION 3.7)
set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)
project(MyProject VERSION 1.0.0)
set(SDL2_SOURCE_DIR “${CMAKE_SOURCE_DIR}/extern/SDL2”)
add_subdirectory(extern/SDL2)
add_subdirectory(src)
Here is an example of my src CMakeLists.txt:
set(PROJECT_NAME MyProject)
file(GLOB HEADER_FILES "${CMAKE_SOURCE_DIR}/include/*.h")
file(GLOB SOURCES "*.cpp")
add_library(${PROJECT_NAME} ${SOURCES} ${HEADER_FILES})
target_include_directories(${PROJECT_NAME} PUBLIC "${CMAKE_SOURCE_DIR}/include")
target_link_libraries(${PROJECT_NAME} PRIVATE SDL2main SDL2-static)
set_target_properties( ${PROJECT_NAME}
PROPERTIES
ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/lib"
LIBRARY_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/lib"
RUNTIME_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/bin"
)

add_subdirectory() will process the subdirectory as a cmake porject (process the provided CMakeLists.txt for SDL). If you read that CMakeLists.txt, you'd see that it add the include directories relative to SDL2_SOURCE_DIR, which is empty by default.
What I would try is to set SDL2_SOURCE_DIR to ${CMAKE_CURRENT_SOURCE_DIR}/extern/SDL2 to make the path absolute. Like that SDL include dirs will be valid everywhere in your project.
You can also manually add the correct includes by using the include_directories() directive.

Related

How do I include the assimp library in the project via CMake?

I followed the asssimp library's installation guide, which used Visual Studio and did all the necessary steps to include it in the project through the GUI when I did everything through pure CMake and MinGW.
I need to include headers and two library files in my project: assimp-[...].dll and assimp-[...].lib
My assimp proj hierarchy
I started to figure out how to write my own CMakeLists.txt and came up with this:
cmake_minimum_required(VERSION 3.2 FATAL_ERROR)
project(Assimp)
add_library(assimp SHARED IMPORTED GLOBAL)
file(GLOB_RECURSE ROOT_SOURCE "./assimp/*.cpp")
file(GLOB_RECURSE ROOT_INLINE "./assimp/*.inl")
file(GLOB_RECURSE ROOT_HPP "./assimp/*.hpp")
file(GLOB_RECURSE ROOT_HEADER "./assimp/*.h")
file(GLOB_RECURSE COMPILER_HEADER "./assimp/Compiler/*.h")
file(GLOB_RECURSE PORT_HEADER "./assimp/port/AndroidJNI/*.h")
source_group("Compiler Files" FILES ${COMPILER_HEADER})
source_group("Port Files" FILES ${PORT_HEADER})
include(GNUInstallDirs)
if(BUILD_STATIC_LIBS)
add_library(assimp_static STATIC
${ROOT_SOURCE} ${ROOT_INLINE} ${ROOT_HPP}
${ROOT_HEADER} ${COMPILER_HEADER} ${PORT_HEADER}
)
target_link_libraries(assimp_static PUBLIC assimp)
add_library(assimp::assimp_static ALIAS assimp_static)
endif()
if(BUILD_SHARED_LIBS)
add_library(assimp_shared SHARED
${ROOT_SOURCE} ${ROOT_INLINE} ${ROOT_HPP}
${ROOT_HEADER} ${COMPILER_HEADER} ${PORT_HEADER}
)
target_link_libraries(assimp_shared PUBLIC assimp)
add_library(assimp::assimp_shared ALIAS assimp_shared)
endif()
set_property(TARGET assimp PROPERTY IMPORTED_LOCATION "${PROJECT_SOURCE_DIR}/external/assimp/lib/assimp-vc143-mtd.dll")
set_property(TARGET assimp PROPERTY IMPORTED_IMPLIB "${PROJECT_SOURCE_DIR}/external/assimp/lib/assimp-vc143-mtd.lib")
After that I'm linking it in the main CMakeLists.txt:
add_executable(${PROJECT_NAME} [src code files here])
add_subdirectory(external/assimp)
target_link_libraries(${PROJECT_NAME} PRIVATE assimp)
But after that, I can't see any header from this library, as well as its directory, and I'm not even sure if the dynamic libraries from the "lib" folder are included correctly.
What am I doing wrong?

CMake: Cannot link to a static library in a subdirectory

I have the following folder structure in my c++ project
*--build
|---(building cmake here)
|
*--main.cpp
|
*--CMakeLists.txt (root)
|
*--modules
|---application
|------app.h
|------app.cpp
|------CMakeLists.txt
And the code below for both CMakeLists.txt files:
CMakeLists.txt (module)
cmake_minimum_required(VERSION 3.15.2)
file(GLOB APPLICATION_HEADERS *.h *.hpp)
file(GLOB APPLICATION_SRC *.c *.cpp)
add_library(app_lib STATIC
${APPLICATION_HEADERS}
${APPLICATION_SRC})
target_include_directories(${PROJECT_NAME} PUBLIC ${CMAKE_CURRENT_LIST_DIR})
CMakeLists.txt (root)
cmake_minimum_required(VERSION 3.15.2)
project(main)
enable_language(C CXX)
#set directories
set(CMAKE_BINARY_DIR build)
set(CMAKE_CONFIGURATION_TYPES UNIX)
set(CMAKE_MODULES_DIR ${SOURCE_DIR}/cmake)
add_executable(${PROJECT_NAME} main.cpp)
# Build sub-modules
include_directories(modules/application)
add_subdirectory(modules/application)
find_library(MY_APP_LIB app_lib REQUIRED)
target_link_libraries(${PROJECT_NAME} PUBLIC ${MY_APP_LIB})
However, when I do cmake .. in my build directory, it seems like my app library just doesn't build and it doesn't link to it. I end up with the following error:
CMake Error at CMakeLists.txt:80 (find_library):
Could not find MY_APP_LIB using the following names: app_lib
I tried looking at other stackoverflow questions but it seems like I'm missing something. Any help is appreciated!
Thanks!
You don't need to use find_* to locate the library. In fact you cannot locate the library this way, since find_library searches the file system for the library during configuration, i.e. before anything gets compiled.
There's good news though: If the targets are created in the same cmake project, you can simply use the name of the cmake target as parameter for target_link_libraries:
...
add_library(app_lib STATIC
${APPLICATION_HEADERS}
${APPLICATION_SRC})
# note: this should be a property of the library, not of the target created in the parent dir
target_include_directories(app_lib PUBLIC .)
...
add_subdirectory(modules/application)
target_link_libraries(${PROJECT_NAME} PUBLIC app_lib)
You don't need to do find_library for your own targets, just link directly to app_lib:
target_link_libraries(${PROJECT_NAME} PUBLIC app_lib)

CMakeLists include Header File from subdirectories

I am trying to work with CMake for the first time and am struggling to link header files into my main. My cmake directory looks like this:
Project
| CmakeLists.txt
| src
|| CMakeLists.txt
|| Main.cpp
| Libs
|| CMakeLists.txt
|| headers
|||obstacle_detection.hpp
||source
|||obstacle_detection.cpp
|build
||"build files"
I would like to link the files in the headers folder to main, but what I currently have does not appear to work. The following runs the CMake command correctly but fails to compile with the make command, being unable to find the given header file. My CMakeLists files are as follows:
Project:
cmake_minimum_required(VERSION 3.17)
project(Sensivision)
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}")
find_package(OpenCV REQUIRED)
find_package(realsense2 REQUIRED)
find_library(darknet REQUIRED)
add_subdirectory(libs)
add_subdirectory(src)
target_link_libraries(${PROJECT_NAME} obstacle_detection)
Libs:
add_library(
obstacle_detection
headers/obstacle_detection.hpp
sources/obstacle_detection.cpp
)
target_link_directories(obstacle_detection PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
src:
add_executable(${PROJECT_NAME} main.cpp)
target_link_libraries(${PROJECT_NAME} ${OpenCV_LIBS})
target_link_libraries(${PROJECT_NAME} ${realsense2_LIBRARY})
My include in main.cpp is
include <obstacle_detection.hpp>
I have also tried
include <headers/obstacle_detection.hpp>
and
include <obstacle_detection>
Each gives the error:
obstacle_detection.hpp: no such file or directory
What am I doing incorrectly to link the header to the main?
You haven't added any include directories to the obstacle_detection library. By listing the header file in the add_library call, this may allow the header to be displayed in an IDE, but it doesn't do anything for compilation. You should use target_include_directories to add the headers directory as an include directory for the obstacle_detection library. Otherwise, it, and other consuming targets, will have no knowledge of the headers in that directory.
add_library(
obstacle_detection
headers/obstacle_detection.hpp
sources/obstacle_detection.cpp
)
# Add this line.
target_include_directories(obstacle_detection PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/headers)
# Not sure this line is necessary, as it doesn't appear you actually link anything...
target_link_directories(obstacle_detection PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
You haven't shown the CMake code in the src directory, but be sure to link the obstacle_detection library target to the main target, e.g.:
target_link_libraries(MyExeTarget PRIVATE obstacle_detection)
In addition, because this header file is local, it is best if you use quotes to include the header:
#include "obstacle_detection.hpp"
You can use target_include_directories to add folder where your headers are located and #include <header.hpp> where needed.
Ex:
libs cmake:
add_library(
obstacle_detection
headers/obstacle_detection.hpp
sources/obstacle_detection.cpp
)
target_include_directories(obstacle_detection PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
cpp:
#include <headers/obstacle_detection.hpp>

How To Include External Libraries in CMake Project

I am confused on how to statically include the source code of SDL2. I am trying to do this to make a library I am working on more portable.
When I was setting this up as executable the library was compiled with it fine, but when I changed it to a library it wouldn't include the library.
Currently, when I try to include my library in another project it says "Cannot open include file: 'SDL2/SDL.h': No such file or directory". So it leads me to think that the cause of the error is that the include directories aren't exported with the static library.
My Filesystem:
include
--Header Files
src
--Source Files
extern
--SDL2
build
Here is an example of the file causing the error:
#include <iostream>
#include <SDL.h> //Error
using namespace std;
/* The code */
Here is an example of my main CMakeLists.txt:
cmake_minimum_required(VERSION 3.7)
set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON)
project(MyProject VERSION 1.0.0)
set(SDL2_SOURCE_DIR “${CMAKE_SOURCE_DIR}/extern/SDL2”)
add_subdirectory(extern/SDL2)
add_subdirectory(src)
Here is an example of my src CMakeLists.txt:
set(PROJECT_NAME MyProject)
file(GLOB HEADER_FILES "${CMAKE_SOURCE_DIR}/include/*.h")
file(GLOB SOURCES "*.cpp")
add_library(${PROJECT_NAME} ${SOURCES} ${HEADER_FILES})
target_include_directories(${PROJECT_NAME} PUBLIC "${CMAKE_SOURCE_DIR}/include" PUBLIC "${CMAKE_SOURCE_DIR}/extern/SDL2/include")
target_link_libraries(${PROJECT_NAME} PRIVATE SDL2main SDL2-static)
set_target_properties( ${PROJECT_NAME}
PROPERTIES
ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/lib"
LIBRARY_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/lib"
RUNTIME_OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/bin"
)
From sdl2 CMakeLists.txt try:
set(SDL_STATIC 1)
add_subdirectory(extern/SDL2) # And I recommend EXCLUDE_FROM_ALL
Also to be sure add a check:
foreach(i IN ITEMS SDL2main SDL2-static)
if(NOT TARGET ${i})
message(FATAL_ERROR "${i} is not a target")
endif()
endif()
target_link_libraries(${PROJECT_NAME} PRIVATE SDL2main SDL2-static)

Include Eigen library for Xcode project via CMake/CMakeLists.txt

I've got the following CMakeLists.txt (in my "project" folder) file for my project.
# define new project
PROJECT(SETUPMARKERTEST)
CMAKE_MINIMUM_REQUIRED(VERSION 2.8.0 FATAL_ERROR)
if(UNIX)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
endif(UNIX)
# Set static build for GLFW
SET(BUILD_SHED_LIBS OFF)
ADD_SUBDIRECTORY(ext/glfw-3.1.1)
# Set shared lib build for the rest
SET(BUILD_SHARED_LIBS ON)
# Find dependencies
SET(EIGEN_INCLUDE_DIR "${CMAKE_SOURCE_DIR}/ext/Eigen-3.1.2")
FIND_PACKAGE(OpenCV REQUIRED)
# Set header and source files
SET(MAR_Test_SOURCES
src/main.cpp
src/MarkerTracker.h src/MarkerTracker.cpp
src/PoseEstimation.h src/PoseEstimation.cpp
)
# define executable
ADD_EXECUTABLE(${PROJECT_NAME} ${MAR_Test_SOURCES})
# define additional include directories and linking targets
INCLUDE_DIRECTORIES("ext/glfw-3.1.1/include" ${EIGEN_INCLUDE_DIR} ${OpenCV_INCLUDE_DIRS})
TARGET_LINK_LIBRARIES(${PROJECT_NAME} ${OpenCV_LIBS} glfw ${OPENGL_glu_LIBRARY} ${GLFW_LIBRARIES})
And my Eigen folder is in "project/ext/Eigen/3.1.2/Eigen/".
Somehow when I created my project for Xcode (in "project/buildXcode/" with Cmake .. -G "Xcode") and run it, Xcode throws me the error:
So I guess there is some error in my CMakeLists.txt, unfortunately I received that file and I'm new to CMake and thus didn't write it on my own nor am I very skilled with CMake.
Do you know what causes the error and can you fix the CMakeLists.txt that my project runs with the Eigen library?
Unfortunately it looks like windows is having no problem with this, whereas mac is bleating.
You just have to use
#include <Eigen/Dense>
instead of
#include <Eigen\Dense>
...pretty stupid error.