M_PI not declared on windows about libosmscout HOT 5 CLOSED

In the end I was able to solve it changing the content of the Math.h file like this:

#include <cmath>

#if defined(_WIN32) || defined(_WIN64)
  #ifndef _USE_MATH_DEFINES
    #define _USE_MATH_DEFINES
  #endif
#include <math.h>
#endif

@Framstag I could create a PR so if you consider it is worthy and there is no other solution, maybe you could add it to master,

Thanks

from libosmscout.

The clean solution would be to use https://en.cppreference.com/w/cpp/numeric/constants - but we are not yet C++20 :-(

For our builds we set the define via compiler options (take a look at meson.build for example). So this is fixed a cenral place. Would this solution possible for you, too?

from libosmscout.

I'm actually using CMake, and I can see the macro definition is included in the CMakelist of this project. The compilation of the library for windows is done as follows:

if not exist "%LIBOSMSCOUT_SOURCE_PATH%" git clone %LIBOSMSCOUT_REPO% %LIBOSMSCOUT_SOURCE_PATH%

if not exist "%LIBOSMSCOUT_VSPROJECT_PATH%" mkdir "%LIBOSMSCOUT_VSPROJECT_PATH%"
cd "%LIBOSMSCOUT_VSPROJECT_PATH%"

cmake -G "Visual Studio 16 2019"^
    -DCMAKE_INSTALL_PREFIX="%DEPENDENCIES_INSTALLATION_PATH:\=/%"^
    -DCMAKE_CXX_FLAGS_RELEASE="/EHsc"^
    -DOSMSCOUT_BUILD_TOOL_STYLEEDITOR=OFF^
    -DOSMSCOUT_BUILD_TOOL_OSMSCOUT2=OFF^
    -DOSMSCOUT_BUILD_TESTS=OFF^
    -DOSMSCOUT_BUILD_CLIENT_QT=OFF^
    -DOSMSCOUT_BUILD_DEMOS=OFF^
    "%LIBOSMSCOUT_SOURCE_PATH%"

cmake --build . --config=Release --target install

This process is done correctly. The library get installs in my project, however, after that, when compiling my project itself, some lines below in the .bat file. So far, everything seems to be configured correctly, but the error is still comming up, as far as I don't include the lines stated in the previuos comment. I'm sure there is something I'm doing in the worng way or missing something...

Thank you so much for your quick reply!

from libosmscout.

The relevant code for libosmscout is in the CMakeList.txt in the root directory in line 154

add_definitions(-D_USE_MATH_DEFINES)

It is possible, that you add this you build, too?

from libosmscout.

Finally solved. As you mentioned, I had to add add_definitions(-D_USE_MATH_DEFINES) to my CMake file as I was including the math.h header indirectly within my project, so my project needed the _USE_MATH_DEFINES macro to be activated.

Thanks.

from libosmscout.