Problems with building( Cmake and Sdl2)

[mrhatkat]

Hi everyone,
I've been having problems with building the game engine. I tried following the steps on the wiki and the README but couldn't find the proper files like build.bat. I was able to get everything but sdl2 to work in cmake by adding the locations of the config.cmake for every library,but for some reason I can't get this approach to work for sdl2. I am on a windows machine running Windows 10 and had to install glew,zlib,boost,glm,and freetype2 to get this far. Is there an easier way to build this that I am missing or is something else wrong?

[Quaker762]

Hi,

The README and wiki are horribly out of date, as I haven't worked on this in a while (though I have recently restarted to project in a modular form, called OpenHill that'll support both SH2 and SH3. The Engine's a shared library that can be used by either game for more common stuff like lighting, but I digress). It's currently a private repository, but I can make it public if you'd like to help work on it.

If you at #132, and look at the files changed, you should be able to get it to build on Windows. Both @z33ky and myself both developed this on Linux, so Windows was a bit of an afterthought.

Let me know if I you need anymore assistance.

Cheers,
Jesse

[mrhatkat]

OpenHill sounds like an interesting project. I'd love to take a look at it and see if I can help out. I'm also going to try looking at #132. Thanks for the help!

[mrhatkat]

Still no luck. I tried making the build.bat file from issue #132 and the sdl.cmake file,but I still ran into problems:

CMake Error at platform/win32/cmake/FindSDL2.cmake:188 (include):
include could not find load file:

C:/Users/Austin/Desktop/sh3/sh3redux/platform/win32/cmake/FindPackageHandleStandardArgs.cmake
Call Stack (most recent call first):
tests/CMakeLists.txt:7 (find_package)

Could NOT find SDL (missing: SDL_LIBRARY) (found version "2.0.9")

CMake Error at tests/CMakeLists.txt:15 (include_directories):
include_directories given empty-string as include directory.

CMake Error at tests/CMakeLists.txt:16 (include_directories):
include_directories given empty-string as include directory.

[z33ky]

Do you use a package-manager like MinGW or Cygwin, did you download pre-build libraries or did you compile the libraries yourself from source?
And if one of the latter, do you use Visual Studio?

[mrhatkat]

I tried just downloading the libraries manually, building them using cmake, and then manually linking the include directories and libraries using the cmake GUI. Would you recommend using Cygwin or MinGW? Also after messing around with the cmakelists, I was able to get a visual studio solution as output from cmake,but I was unable to build the solution.

[z33ky]

Same as @Quaker762, I use Linux. I just wanted to get a clearer picture of your setup.
MinGW and Cygwin impose a more Linux-like environment, which would probably make it easier, but ideally we should try and fix up our build-scripts.

In theory, after building the libraries you should just be able to set the directories/files for each library in cmake-gui and you should be good to go. Like with the error above, where it complains about missing SDL_LIBRARY, you should just be able to set that variable to the path of your SDL2.dll and it should proceed from there.

Can you post your changes to the CMakeLists.txt? Even if you just hard-coded some paths, we should be able to improve our scripts based on the changes you needed to make.
Are you getting any error messages from attempting to build your generated solution?

[mrhatkat]

All I did was comment out a few lines of code in the tests/cmakelists.txt:
#include_directories(SYSTEM "${OPENGL_INCLUDE_DIR}") #include_directories(SYSTEM "${SDL2_INCLUDE_DIRS}")

and source/cmakelists.txt:
#include_directories(SYSTEM "${OPENGL_INCLUDE_DIR}") include_directories(SYSTEM "${SDL2_INCLUDE_DIR}")
I also changed DIRS to DIR in these two lines. I'm starting to think that might have caused the errors in my solution though, since the error messages say that a lot of header files and the sdl library are missing. I also included the SDL2.cmake file from https://github.com/tcbrindle/sdl2-cmake-scripts in my cmake module directory.

I'm thinking I also don't have the libraries set up correctly. I have pretty strong familiarity with Linux, what are the steps you would take for installing the libraries and I'll see if i can figure out how to do that in Windows.

[z33ky]

Yeah, the directives you've commented out are needed.
You don't need to do anything special to install the libraries, you just need to know where to find the DLL/so-files and where to find the header files.
When you run the CMakeLists.txt with cmake-gui and click on "Configure" you should get a list of variables. Where CMake is unable to find stuff in their standard paths, you can just insert the paths where you downloaded the library. The *_INCLUDE_DIR usually need to point to a include-subdirectory and the *_LIBRARY should point to your built DLLs (or maybe the .lib-files, I can't remember).
As for DIR vs DIRS, CMake scripts are inconsistent about that. I think it should work as is, but I could just as well be off on some.

SDL2 should build a corresponding CMake script (see https://hg.libsdl.org/SDL/file/6a5107360fbc/CMakeLists.txt#l1820), which obsolete the Find*.cmake script as far as I understand. If you set SDL2_ROOT_DIR EDIT: sorry, that's SDL2_DIR to the directory that contains the built SDL2Config.cmake-file, the include- and library paths should get set correctly. If that variable doesn't exist you can just add it manually and it should be picked up when you hit "Configure" again.

I think the OpenGL-headers are somewhere in the MSVC folder. Do a file-search for "gl.h" in there.

[z33ky]

Also try replacing "${SDL2_LIBRARIES}" in the CMakeLists.txt with SDL2 and remove the lines saying include_directories(SYSTEM "${SDL2_INCLUDE_DIR}"). It seems like SDL2 only supports imported targets, which don't define those variables anymore.

[mrhatkat]

That makes it so that I can get through Cmake, but I'm still having 145 errors in the visual studio solution.

[z33ky]

Are they related to SDL2? It might need SDL2::SDL2 instead.
Otherwise paste the errors on a Github Gist or something, they may be incompatibilities between compilers.

[mrhatkat]

Sdl2 seems fine, the problem seems to be with zlib using unistd.h which doesn't exist on windows, and API Entry is undefined which I think is an OpenGL problem.

[z33ky]

Try replacing if(CYGWIN) in the top-level CMakeLists.txt, line 117 by if(CYGWIN OR MSVC). That should fix your APIENTRY issue.
For zlib/unistd.h, an Internet search suggests that this is due to an incorrectly generated zconf.h within the zlib build. Did you also build zlib via Visual Studio?

EDIT:
You can try applying these changes to your zconf.h: http://trac.wxwidgets.org/attachment/ticket/17745/minor-changes-to-make-MSVC-happy.patch

[mrhatkat]

I used something called "GNUWin32" which I read was a zlib library for Windows,but that might be causing the problems.

[z33ky]

Yeah, that likely used something like MinGW, which provides a unistd.h.
Try finding a version of it built with MSVC - or build it yourself. Note that all the libraries you downloaded must be built with MSVC, possibly even with the same version, I'm not sure.

As I said before, using something like MinGW or Cygwin (I think the former is more popular) is probably easier, but still I appreciate you trying and sticking with it so far :)