3

I'm trying to run mathgl with cmake and I'm having some problems. The code for the file test001.cpp is as follows:

#include <stdio.h>
#include <mgl2/qt.h>
int sample(mglGraph *gr)
{
  gr->Rotate(60,40);
  gr->Box();
  return 0;
}
int main(int argc,char **argv)
{
  mglQT gr(sample,"MathGL examples");
  return gr.Run();
}

I compile it with this CMakeLists.txt

cmake_minimum_required(VERSION 2.8.3)
project (test001)
SET(CMAKE_MODULE_PATH ${test001_SOURCE_DIR})

# FIND_PACKAGE(Qt REQUIRED)
find_package(MathGL)
include_directories(
    ${MathGL_INCLUDE_DIRS}
)
add_executable(test001 test001.cpp)
target_link_libraries(test001 ${MathGL_LIBRARIES})

Which needs the following cmake module:

FIND_PATH(MATHGL_INCLUDE_DIR NAMES mgl2/mgl.h
  PATHS
  /opt/local/include
  /usr/include
  /usr/local/include
)

FIND_LIBRARY(MATHGL_LIB NAMES mgl
  PATHS
  /opt/local/lib
  /usr/local/lib
  /usr/lib
)

IF (MATHGL_INCLUDE_DIR AND MATHGL_LIB)
  SET(MATHGL_FOUND TRUE)
  MESSAGE(STATUS "MATHGL found")
  MESSAGE(STATUS "MATHGL Include dirs:" ${MATHGL_INCLUDE_DIR})
  MESSAGE(STATUS "MATHGL Library:" ${MATHGL_LIB})
ELSE (MATHGL_INCLUDE_DIR AND MATHGL_LIB)
  MESSAGE(STATUS "MATHGL was not found")
ENDIF(MATHGL_INCLUDE_DIR AND MATHGL_LIB)

All the files are in the same folder.

I run then cmake .. inside a folder called build and I get apparently a good answer:

-- The C compiler identification is GNU 4.9.2
-- The CXX compiler identification is GNU 4.9.2
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- MATHGL found
-- MATHGL Include dirs:/usr/include
-- MATHGL Library:/usr/lib/libmgl.so
-- Configuring done
-- Generating done
-- Build files have been written to: /home/fogg/dev/c/mathgl/build

But then I get a compilation error as if I wasn't linking the program, but I'm doing it in the CMakeLists.txt file.

Scanning dependencies of target test001
[100%] Building CXX object CMakeFiles/test001.dir/test001.cpp.o
Linking CXX executable test001
CMakeFiles/test001.dir/test001.cpp.o: In function `mglGraph::mglGraph(int, int, int)':
test001.cpp:(.text._ZN8mglGraphC2Eiii[_ZN8mglGraphC5Eiii]+0x3b): undefined reference to `mgl_create_graph_gl'
test001.cpp:(.text._ZN8mglGraphC2Eiii[_ZN8mglGraphC5Eiii]+0x57): undefined reference to `mgl_create_graph'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglGraph::~mglGraph()':
test001.cpp:(.text._ZN8mglGraphD2Ev[_ZN8mglGraphD5Ev]+0x28): undefined reference to `mgl_use_graph'
test001.cpp:(.text._ZN8mglGraphD2Ev[_ZN8mglGraphD5Ev]+0x42): undefined reference to `mgl_delete_graph'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglGraph::SetFontSize(double)':
test001.cpp:(.text._ZN8mglGraph11SetFontSizeEd[_ZN8mglGraph11SetFontSizeEd]+0x2a): undefined reference to `mgl_set_font_size'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglGraph::Rotate(double, double, double)':
test001.cpp:(.text._ZN8mglGraph6RotateEddd[_ZN8mglGraph6RotateEddd]+0x4e): undefined reference to `mgl_rotate'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglGraph::Box(char const*, bool)':
test001.cpp:(.text._ZN8mglGraph3BoxEPKcb[_ZN8mglGraph3BoxEPKcb]+0x2c): undefined reference to `mgl_box_str'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglQT::mglQT(int (*)(mglGraph*), char const*)':
test001.cpp:(.text._ZN5mglQTC2EPFiP8mglGraphEPKc[_ZN5mglQTC5EPFiP8mglGraphEPKc]+0x34): undefined reference to `mgl_draw_graph'
test001.cpp:(.text._ZN5mglQTC2EPFiP8mglGraphEPKc[_ZN5mglQTC5EPFiP8mglGraphEPKc]+0x50): undefined reference to `mgl_create_graph_qt'
CMakeFiles/test001.dir/test001.cpp.o: In function `mglQT::Run()':
test001.cpp:(.text._ZN5mglQT3RunEv[_ZN5mglQT3RunEv]+0xd): undefined reference to `mgl_qt_run'
collect2: error: ld returned 1 exit status
make[2]: *** [test001] Error 1
make[1]: *** [CMakeFiles/test001.dir/all] Error 2
make: *** [all] Error 2

Side-note: this program compiles perfectly well when using g++ test001.cpp -lmgl-qt -lmgl -o test001. Any ideas?

4

4 回答 4

3

我使用的FindMathGL.cmake是从本网站下载的，显然它包含一些错误。我更正了文件并在接下来发布它，它可能对将来的某人有用。

FIND_PATH(MathGL_INCLUDE_DIRS NAMES mgl2/mgl.h
  PATHS
  /opt/local/include
  /usr/include
  /usr/local/include
)

FIND_LIBRARY(MathGL_LIB NAMES mgl
  PATHS
  /opt/local/lib
  /usr/local/lib
  /usr/lib
)
FIND_LIBRARY(MathGL_QT_LIB NAMES mgl-qt
  PATHS
  /opt/local/lib
  /usr/local/lib
  /usr/lib
)


SET(MathGL_LIBRARIES ${MathGL_LIB} ${MathGL_QT_LIB})

IF (MathGL_INCLUDE_DIRS AND MathGL_LIBRARIES)
  SET(MathGL_FOUND TRUE)
  MESSAGE(STATUS "MathGL found")
  MESSAGE(STATUS "MathGL Include dirs:" ${MathGL_INCLUDE_DIRS})
  MESSAGE(STATUS "MathGL Library:" ${MathGL_LIB})
ELSE (MathGL_INCLUDE_DIRS AND MathGL_LIBRARIES)
  MESSAGE(STATUS "MathGL was not found")
ENDIF(MathGL_INCLUDE_DIRS AND MathGL_LIBRARIES)
于 2015-11-03T22:30:51.280 回答
1

对于寻找此问题的其他所有人：

在从 sourceforge 下载的包中 mathgl-code 文件夹下的 scripts 文件夹中有一个名为 FindMathGL2.cmake 的文件。

要使用它，请在 CMakeLists.txt 文件中包含以下行：

set( CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} /path-to-mathgl-code-folder/scripts)
find_package(MathGL2 REQUIRED)
include_directories(${MATHGL2_INCLUDE_DIRS})
link_directories(${CMAKE_PREFIX_PATH}/lib/)

替换path-to-mathgl-code-folder为合适的路径。

例如，在我的项目中：

set( CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${PROJECT_SOURCE_DIR}/cmake_add/)

其中 cmake_add 是我项目中的一个文件夹，仅包含FindMathGL2.cmake

PS：您可以在文件 FindMathGL2.cmake 中找到更多自定义说明

PS2：在 ubuntu 上安装 dev mathgl 包：

sudo apt-get install libmgl-dev
于 2019-03-26T07:21:08.263 回答
1

不严格相关，对于后代：与 MathGL 2.4 捆绑的 FindMathGL2.cmake 版本由于某种原因不处理 GLUT 库（其他组件可能也没有链接）。

您必须添加一个部分以添加/usr/local/lib/libmgl-glut.so到MATHGL2_LIBRARY.

于 2019-12-29T07:53:58.520 回答
1

对于任何查看@silgon 答案并尝试使其在 Mac 上运行的人：

  1. brew 默认找不到 MathGL。添加水龙头：

    brew tap brewsci/homebrew-science

  2. 即使你现在尝试安装 MathGL，它也缺乏 QT、FLTK 等支持。需要像这样从源安装：

    brew install --build-from-source mathgl --with-qt --with-wxmac

  3. 现在头文件和库位于版本控制目录中，例如 /usr/local/Cellar/mathgl/2.3.5.1_4/lib/ 和 /usr/local/Cellar/mathgl/2.3.5.1_4/include/mgl2/ 硬编码是我们想要的避免。要使 CMake 在上面工作，请像这样修改它

    FIND_PATH(MathGL_INCLUDE_DIRS NAMES mgl2/mgl.h PATHS /opt/local/include /usr/include /usr/local/include /usr/local/Cellar/mathgl/*/ PATH_SUFFIXES lib )

您要使用的每个头文件和库都相同。

于 2019-07-13T04:16:01.007 回答