Trying to build on GLES platforms fails

[vanfanel]

@alfrix:

I was trying to get this core to build on non-Xorg, GLES-based platforms like the Raspberry Pi or any X86 PC with no Xorg server running (RetroArch is know for running on KMS/DRM+GLES) but it fails:

../../gapi_gl.h:92:24: fatal error: GL/glx.h: No such file or directory
     #include <GL/glx.h>
                        ^
compilation terminated.

I am forcing compilation by defining a non-Xorg OS on core.h like this:

#elif __KMSDRM__
    #define _OS_KMSDRM 1
    #define _GAPI_GL   1
    #define _GAPI_GLES 1

    #define DYNGEOM_NO_VBO

and also using that OS on gapi_gl.h like this on line 48:

#elif defined(_OS_RPI) || defined(_OS_CLOVER) || defined(_OS_KMSDRM)

Then I added a new platform definition on the libretro platform Makefile, like this:

else ifeq ($(platform), rpi)
   TARGET := $(TARGET_NAME)_libretro.so
   fpic := -fPIC
   SHARED := -shared -Wl,--version-script=link.T -Wl,--no-undefined
   CXXFLAGS += -D__KMSDRM__
   CFLAGS += -D__KMSDRM__
   LIBS += -lpthread
   GLES = 1

And then it builds on the X-less Pi as intended, but all I get on loading PSX data is a segfault... Can you please test?

[alfrix]

I'm sorry, but i don't have a rpi or similar platform to test this El lun., 10 de dic. de 2018 19:02, Manuel Alfayate Corchete < notifications@github.com> escribió:

…

@alfrix <https://github.com/alfrix>: I was trying to get this core to build on non-Xorg, GLES-based platforms like the Raspberry Pi or any X86 PC with no Xorg server running (RetroArch is know for running on KMS/DRM+GLES) but it fails: ../../gapi_gl.h:92:24: fatal error: GL/glx.h: No such file or directory #include <GL/glx.h> ^ compilation terminated. I am forcing compilation by defining a non-Xorg OS on core.h like this: #elif __KMSDRM__ #define _OS_KMSDRM 1 #define _GAPI_GL 1 #define _GAPI_GLES 1 #define DYNGEOM_NO_VBO and also using that OS on gapi_gl.h like this on line 48: #elif defined(_OS_RPI) || defined(_OS_CLOVER) || defined(_OS_KMSDRM) Then I added a new platform definition on the libretro platform Makefile, like this: else ifeq ($(platform), rpi) TARGET := $(TARGET_NAME)_libretro.so fpic := -fPIC SHARED := -shared -Wl,--version-script=link.T -Wl,--no-undefined CXXFLAGS += -D__KMSDRM__ CFLAGS += -D__KMSDRM__ LIBS += -lpthread GLES = 1 And then it builds on the X-less Pi as intended, but all I get on loading PSX data is a segfault... Can you please test? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#14>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABMIBf6bg4e-KSQngkpYZQGbfWNUHMhcks5u3tnZgaJpZM4ZMQ8T> .

[vanfanel]

@alfrix : Any GNU/Linux PC will do.

[vanfanel]

@alfrix : Trying to build a GLES version with current sources I get this:

../../gapi_gl.h:194:45: error: ‘void (* glGenerateMipmap)(GLenum)’ redeclared as different kind of symbol
         PFNGLGENERATEMIPMAPPROC             glGenerateMipmap;
                                             ^~~~~~~~~~~~~~~~
In file included from ./libretro-common/include/glsym/rglgen_headers.h:55,
                 from ./libretro-common/include/glsym/rglgen.h:32,
                 from ./libretro-common/include/glsym/glsym.h:26,
                 from main.cpp:7:
/usr/include/GLES2/gl2.h:576:29: note: previous declaration ‘void glGenerateMipmap(GLenum)’
 GL_APICALL void GL_APIENTRY glGenerateMipmap (GLenum target);
                             ^~~~~~~~~~~~~~~~
In file included from ../../core.h:607,
                 from ../../game.h:4,
                 from main.cpp:11:
../../gapi_gl.h:207:45: error: ‘GLuint (* glCreateProgram)()’ redeclared as different kind of symbol
         PFNGLCREATEPROGRAMPROC              glCreateProgram;
                                             ^~~~~~~~~~~~~~~
In file included from ./libretro-common/include/glsym/rglgen_headers.h:55,
                 from ./libretro-common/include/glsym/rglgen.h:32,
                 from ./libretro-common/include/glsym/glsym.h:26,
                 from main.cpp:7:
/usr/include/GLES2/gl2.h:551:31: note: previous declaration ‘GLuint glCreateProgram()’
 GL_APICALL GLuint GL_APIENTRY glCreateProgram (void);
                               ^~~~~~~~~~~~~~~
In file included from ../../core.h:607,
                 from ../../game.h:4,
                 from main.cpp:11:

It's much longer, but you get the idea. I believe something is wrong with these redefinitions...
I use MESA GLES implementation, the most common in GNU/Linux.

[alfrix]

you cannot just turn GLES on linux, you need to extensively modify gapi_gl to add your platform, otherwise it will assume desktop GL each time there is an defined(_OS_LINUX),

[vanfanel]

@alfrix : but "my platform" is libretro, as in src/platform/libretro.
Asuming that Linux=DesktopGL is just plain wrong, as GLES/GLES2 is also widely used in Linux.

Is this core supposed to build on something like the Raspberry Pi?

[alfrix]

i have only tested fedora and ubuntu, i have never seen a x86 distro that comes with gles but not gl,
i'm no expert but you can tell by looking at the code, rpi is treated differently, but again i cannot test it, if you have it, try to fix it and make a PR

[vanfanel]

@alfrix : Desktop GNU/Linux distros are not to be used as a reference when it comes to libretro cores, since LR/RA main point is being able to run the cores in WAY more different ways inside the Linux ecosystem, like SBCs (Pi, etc), consoles (NES/SNES/PSX Classics), etc...

I will give it a go, but I need your help. Can I meet you on IRC or any other method for a fluid comunication?

[alfrix]

Most LR/RA devs, including maintainers hangout on the Discord channel
ask your question directly on #programming
https://discord.gg/GZJKWjJ
the IRC channel is much less populated
http://webchat.freenode.net/?channels=%23retroarch&uio=d4
note that there is a bridge (retrobot) between IRC and discord of the channel #retroarch

[vanfanel]

@alfrix : I don't need general RA/LR or programming advice, but help with the OpenLara core, so I need to contact you.

[alfrix]

i go there regularly, you can PM me if you prefer it, once you join the channel.
you can also find xproger in https://discord.gg/6mc4Jw

[vanfanel]

@alfrix : Does xprogger also collaborate in the libretro port?

[XProger]

@vanfanel I'll help all I can :)

[vanfanel]

@XProger : Do you use IRC? What server/channel?

[XProger]

@vanfanel nope, only discord and telegram

[vanfanel]

Can you guys send me a new invite or tell me how to join again? This discord stuff is new to me...