GUI: add resize() and draw()

src/gui/GUI.cc

@@ -100,8 +100,8 @@ namespace jes
 
     int GUI::run()
     {
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        resize();
-        SDL_GL_SwapWindow(m_window);
+        draw();
 
         SDL_Event event;
         while (SDL_WaitEvent(&event))
@@ -113,8 +113,39 @@ namespace jes
                 if (event.key.keysym.sym == SDLK_ESCAPE)
                     break;
             }
+            else if (event.type == SDL_WINDOWEVENT)
+            {
+                switch (event.window.event)
+                {
+                case SDL_WINDOWEVENT_EXPOSED:
+                    draw();
+                    break;
+                case SDL_WINDOWEVENT_RESIZED:
+                    resize();
+                    draw();
+                    break;
+                }
+            }
         }
 
         return 0;
     }
+
+    void GUI::resize()
+    {
+        GLint viewport_size[2];
+        SDL_GetWindowSize(m_window, &viewport_size[0], &viewport_size[1]);
+        glViewport(0, 0, viewport_size[0], viewport_size[1]);
+        for (int i = 0; i < PROGRAM_COUNT; i++)
+        {
+            m_programs[i]->use();
+            glUniform2iv(m_programs[i]->get_uniform("viewport_size"), 1, &viewport_size[0]);
+        }
+    }
+
+    void GUI::draw()
+    {
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        SDL_GL_SwapWindow(m_window);
+    }
 }

src/gui/GUI.h

@@ -22,6 +22,8 @@ namespace jes
         int run();
     protected:
         bool load_shaders();
+        void resize();
+        void draw();
 
         SDL_Window * m_window;
         FontManagerRef m_font_manager;