Being an optimist, I hope that in the not so distant future Raspian will include a decent SDL 2 implementation. In the meantime, I will enjoy learning about Gosu on my Mac.

Thanks for taking a look into the issue.

Thanks for the reply. I'm afraid I don't know any C++ and only a little C. I found from the compiler that SDL_CreateContext returns a pseudonym for void. I printed this value as an integer, it contained 1. (I'm not sure if this is what you needed or any use).

Please let me know what I can do to help (given my limitations).

This is the line of code that I inserted:

   printf("SDL_GL_CreateContext returns %d\n", int(SDL_GL_CreateContext(window)));

I put that immediately after:

   SDL_Window* window = SDL_CreateWindow("Test SDL 2", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
                                        800, 600, SDL_WINDOW_SHOWN | SDL_WINDOW_OPENGL);
   check_error_sdl(window == nullptr, "Unable to create window");


This is the output:

  ~/SDL2test $ ./sdl2_test
SDL_GL_CreateContext returns 1
~/SDL2test $

It took me a little longer than I had hoped. I wasn't able to get any of the SDL2 test programs working but that was probably because I was making mistakes.

However, by following these instructions - https://solarianprogrammer.com/2015/01/22/raspberry-pi-raspbian-getting-started-sdl-2/ - I was able to compile and run the simple test program at the end of the blog.

I installed gosu 0.9.2 again using the command from the Gosu wiki but still got the "Could not initialize OpenGL / GLES library message" when I ran the tutorial.

(By the way, it seems that the examples don't get installed with 0.9.2)

I'll try to do that over the next few days. If I'm able I'll let you know how I got on.

I tried with Gosu 0.8.7.2 and got a similar error when I tried to run the tutorial program:


pi@raspibplus /usr/local/lib/ruby/gems/2.2.0/gems/gosu-0.8.7.2/examples $ gem list gosu

*** LOCAL GEMS ***

gosu (0.8.7.2)
pi@raspibplus /usr/local/lib/ruby/gems/2.2.0/gems/gosu-0.8.7.2/examples $ ruby Tutorial.rb
Tutorial.rb:84:in initialize': Could not open window: Could not initialize OpenGL / GLES library (RuntimeError)
  from Tutorial.rb:84:in initialize'
  from Tutorial.rb:130:in new'
  from Tutorial.rb:130:in <main>'


I followed the very thorough instructions on https://github.com/gosu/gosu/wiki/Getting-Started-on-Raspbian-(Raspberry-Pi). I'm pretty sure that I got everything correct as I copied all the commands from the wiki page into the command line.

When I run a very simple test program, I get this error:


pi@raspibplus ~/Code/Ruby/Gosu $ ruby test.rb
/usr/local/lib/ruby/gems/2.2.0/gems/gosu-0.9.2/lib/gosu/swig_patches.rb:19:in initialize': Could not create window: Could not initialize OpenGL / GLES library (RuntimeError)
  from /usr/local/lib/ruby/gems/2.2.0/gems/gosu-0.9.2/lib/gosu/swig_patches.rb:19:in initialize'
  from test.rb:4:in initialize'
  from test.rb:15:in new'
  from test.rb:15:in `<main>'
terminate called after throwing an instance of 'std::runtime_error'
  what():  Could not create window: Could not initialize OpenGL / GLES library
Aborted


Any suggestions as to what I may have done incorrectly?

Thanks in advance

Peter