add Window module

src/Window.cc

@@ -0,0 +1,82 @@
+#include "gl3w.h"
+#include "ruby.h"
+#include "Window.h"
+#include <SDL.h>
+
+#define WIDTH   500
+#define HEIGHT  500
+
+typedef struct
+{
+    SDL_Window * sdl_window;
+} Window;
+
+static VALUE ruby_class;
+
+static void Init_Graphics(void)
+{
+    static bool graphics_initialized = false;
+
+    if (graphics_initialized)
+        return;
+
+    if (SDL_Init(SDL_INIT_VIDEO))
+    {
+        rb_raise(rb_eRuntimeError, "Failed to initialize SDL");
+    }
+
+    atexit(SDL_Quit);
+
+    if (gl3wInit() != 0)
+    {
+        SDL_Quit();
+        rb_raise(rb_eRuntimeError, "Failed to gl3wInit()");
+    }
+
+    if (!gl3wIsSupported(3, 0))
+    {
+        SDL_Quit();
+        rb_raise(rb_eRuntimeError, "OpenGL 3.0 is not supported");
+    }
+}
+
+static void Window_free(void * ptr)
+{
+    /* TODO */
+}
+
+static VALUE Window_new(VALUE klass)
+{
+    static bool one_created = false;
+
+    if (one_created)
+    {
+        rb_raise(rb_eRuntimeError, "Only one Window for now");
+    }
+
+    Init_Graphics();
+    Window * window = (Window *)malloc(sizeof(Window));
+    window->sdl_window = SDL_CreateWindow("jes",
+                                          SDL_WINDOWPOS_UNDEFINED,
+                                          SDL_WINDOWPOS_UNDEFINED,
+                                          WIDTH,
+                                          HEIGHT,
+                                          SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
+    if (window->sdl_window == NULL)
+    {
+        free(window);
+        rb_raise(rb_eRuntimeError, "Failed to create SDL window");
+    }
+
+    (void)SDL_GL_CreateContext(window->sdl_window);
+
+    one_created = true;
+
+    return Data_Wrap_Struct(ruby_class, NULL, Window_free, window);
+}
+
+void Window_Init(void)
+{
+    ruby_class = rb_define_class("Window", rb_cObject);
+    rb_define_singleton_method(ruby_class, "new", (VALUE(*)(...))Window_new, 0);
+}

src/Window.h

@@ -0,0 +1,6 @@
+#ifndef WINDOW_H
+#define WINDOW_H
+
+void Window_Init(void);
+
+#endif

src/main.cc

@@ -1,6 +1,7 @@
 #include <iostream>
 #include "GUI.h"
 #include "ruby.h"
+#include "Window.h"
 
 using namespace std;
 
@@ -47,6 +48,7 @@ static int bootstrap()
 {
     int rv = 0;
     int err_state = 0;
+    Window_Init();
     rb_eval_string_protect(
       "load File.expand_path('../../runtime/main.rb', $0)",
       &err_state);