add GL module; move OpenGL loading from Window to GL

src/GL.cc

@@ -0,0 +1,101 @@
+#include "GL.h"
+#include "gl3w.h"
+#include "ruby.h"
+#include "GLBuffer.h"
+#include "GLProgram.h"
+
+enum
+{
+    PROGRAM_TEXT,
+    PROGRAM_BASIC,
+    PROGRAM_RECT,
+    PROGRAM_COUNT
+};
+
+static const char * program_names[PROGRAM_COUNT] = {
+    "text",
+    "basic",
+    "rect",
+};
+
+static VALUE ruby_module;
+static GLBufferRef rect_buffer;
+static GLProgram * programs[PROGRAM_COUNT];
+
+void GL_Init()
+{
+    ruby_module = rb_define_module("GL");
+}
+
+static void load_gl_buffers()
+{
+    static const GLint rect_coords[4][2] = {
+        {0, 0},
+        {1, 0},
+        {0, 1},
+        {1, 1},
+    };
+
+    rect_buffer = new GLBuffer();
+    if (!rect_buffer->create(GL_ARRAY_BUFFER, GL_STATIC_DRAW,
+                             &rect_coords, sizeof(rect_coords)))
+    {
+        rb_raise(rb_eRuntimeError, "Failed to create rectangle VBO");
+    }
+}
+
+void GL_Load()
+{
+    static bool loaded = false;
+
+    if (loaded)
+        return;
+
+    if (gl3wInit() != 0)
+    {
+        rb_raise(rb_eRuntimeError, "Failed to gl3wInit()");
+    }
+
+    if (!gl3wIsSupported(3, 0))
+    {
+        rb_raise(rb_eRuntimeError, "OpenGL 3.0 is not supported");
+    }
+
+    load_gl_buffers();
+
+    rb_funcall(ruby_module, rb_intern("load_shaders"), 0);
+
+    VALUE programs_hash = rb_iv_get(ruby_module, "@programs");
+    for (int i = 0; i < PROGRAM_COUNT; i++)
+    {
+        VALUE program = rb_funcall(programs_hash,
+                                   rb_intern("[]"),
+                                   1,
+                                   ID2SYM(rb_intern(program_names[i])));
+        if (RTEST(program))
+        {
+            programs[i] = GLProgram_FromRuby(program);
+        }
+        else
+        {
+            rb_raise(rb_eLoadError,
+                     "Error resolving %s program",
+                     program_names[i]);
+        }
+    }
+
+    glEnable(GL_SCISSOR_TEST);
+
+    loaded = true;
+}
+
+void GL_Resize(int width, int height)
+{
+    GLint viewport_size[] = {width, height};
+    glViewport(0, 0, width, height);
+    for (int i = 0; i < PROGRAM_COUNT; i++)
+    {
+        glUseProgram(programs[i]->id);
+        glUniform2iv(programs[i]->uniforms[UNIFORM_VIEWPORT_SIZE], 1, &viewport_size[0]);
+    }
+}

src/GL.h

@@ -0,0 +1,8 @@
+#ifndef GL_H
+#define GL_H
+
+void GL_Init();
+void GL_Load();
+void GL_Resize(int width, int height);
+
+#endif

src/Window.cc

@@ -1,4 +1,5 @@
 #include "gl3w.h"
+#include "GL.h"
 #include "GLBuffer.h"
 #include "GLProgram.h"
 #include "ruby.h"
@@ -8,25 +9,9 @@
 #define WIDTH   500
 #define HEIGHT  500
 
-enum
-{
-    PROGRAM_TEXT,
-    PROGRAM_BASIC,
-    PROGRAM_RECT,
-    PROGRAM_COUNT
-};
-
-const char * program_names[PROGRAM_COUNT] = {
-    "text",
-    "basic",
-    "rect",
-};
-
 typedef struct
 {
     SDL_Window * sdl_window;
-    GLBufferRef rect_buffer;
-    GLProgram * programs[PROGRAM_COUNT];
 } Window;
 
 static VALUE ruby_class;
@@ -49,47 +34,6 @@ static void Init_SDL()
     initialized = true;
 }
 
-static void load_gl_buffers(Window * window)
-{
-    static const GLint rect_coords[4][2] = {
-        {0, 0},
-        {1, 0},
-        {0, 1},
-        {1, 1},
-    };
-
-    window->rect_buffer = new GLBuffer();
-    if (!window->rect_buffer->create(GL_ARRAY_BUFFER, GL_STATIC_DRAW,
-                                     &rect_coords, sizeof(rect_coords)))
-    {
-        rb_raise(rb_eRuntimeError, "Failed to create rectangle VBO");
-    }
-}
-
-static void Init_OpenGL()
-{
-    static bool initialized = false;
-
-    if (initialized)
-        return;
-
-    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");
-    }
-
-    glEnable(GL_SCISSOR_TEST);
-
-    initialized = true;
-}
-
 static void Window_free(void * ptr)
 {
     Window * window = (Window *)ptr;
@@ -102,23 +46,19 @@ static void Window_free(void * ptr)
 
 static void resize()
 {
-    GLint viewport_size[2];
+    int width;
+    int height;
     Window * window;
     Data_Get_Struct(window_instance, Window, window);
-    SDL_GetWindowSize(window->sdl_window, &viewport_size[0], &viewport_size[1]);
-    glViewport(0, 0, viewport_size[0], viewport_size[1]);
-    for (int i = 0; i < PROGRAM_COUNT; i++)
-    {
-        glUseProgram(window->programs[i]->id);
-        glUniform2iv(window->programs[i]->uniforms[UNIFORM_VIEWPORT_SIZE], 1, &viewport_size[0]);
-    }
+    SDL_GetWindowSize(window->sdl_window, &width, &height);
+    GL_Resize(width, height);
     rb_funcall(window_instance,
                rb_intern("resize"),
                4,
                INT2FIX(0),
                INT2FIX(0),
-               INT2FIX(viewport_size[0]),
-               INT2FIX(viewport_size[1]));
+               INT2FIX(width),
+               INT2FIX(height));
 }
 
 static VALUE Window_new(VALUE klass)
@@ -149,33 +89,12 @@ static VALUE Window_new(VALUE klass)
 
     (void)SDL_GL_CreateContext(window->sdl_window);
 
-    Init_OpenGL();
-
-    load_gl_buffers(window);
+    GL_Load();
 
     one_created = true;
 
     VALUE rv = Data_Wrap_Struct(ruby_class, NULL, Window_free, window);
     rb_obj_call_init(rv, 0, NULL);
-    VALUE programs = rb_iv_get(rv, "@programs");
-    for (int i = 0; i < PROGRAM_COUNT; i++)
-    {
-        VALUE program = rb_funcall(programs,
-                                   rb_intern("[]"),
-                                   1,
-                                   ID2SYM(rb_intern(program_names[i])));
-        if (RTEST(program))
-        {
-            window->programs[i] = GLProgram_FromRuby(program);
-        }
-        else
-        {
-            delete window;
-            rb_raise(rb_eLoadError,
-                     "Error resolving %s program",
-                     program_names[i]);
-        }
-    }
 
     /* TODO: remove window_instance and map SDL_Window * to Window Ruby object
      * to support multiple windows. */

src/main.cc

@@ -2,6 +2,7 @@
 #include "ruby.h"
 
 #include "Font.h"
+#include "GL.h"
 #include "GLProgram.h"
 #include "GLShader.h"
 #include "Widget.h"
@@ -54,6 +55,7 @@ static int bootstrap()
     int err_state = 0;
 
     Font_Init();
+    GL_Init();
     GLProgram_Init();
     GLShader_Init();
     Widget_Init();