--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Applications/Sdl/SdlEngine.cpp	Thu Apr 27 14:50:20 2017 +0200
@@ -0,0 +1,319 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017 Osimis, Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "SdlEngine.h"
+
+#if ORTHANC_ENABLE_SDL == 1
+
+#include "../../../Resources/Orthanc/Core/Logging.h"
+
+#include <SDL.h>
+
+namespace OrthancStone
+{
+  void SdlEngine::RenderFrame()
+  {
+    if (!viewportChanged_)
+    {
+      return;
+    }
+
+    viewportChanged_ = false;
+
+    if (buffering_.RenderOffscreen(viewport_))
+    {
+      // Do not notify twice when a new frame was rendered, to avoid
+      // spoiling the SDL event queue
+      SDL_Event event;
+      SDL_memset(&event, 0, sizeof(event));
+      event.type = refreshEvent_;
+      event.user.code = 0;
+      event.user.data1 = 0;
+      event.user.data2 = 0;
+      SDL_PushEvent(&event);
+    }
+  }
+
+
+  void SdlEngine::RenderThread(SdlEngine* that)
+  {
+    for (;;)
+    {
+      that->renderFrame_.Wait();
+
+      if (that->continue_)
+      {
+        that->RenderFrame();
+      }
+      else
+      {
+        return;
+      }
+    }
+  }             
+
+
+  KeyboardModifiers SdlEngine::GetKeyboardModifiers(const uint8_t* keyboardState,
+                                                    const int scancodeCount)
+  {
+    int result = KeyboardModifiers_None;
+
+    if (keyboardState != NULL)
+    {
+      if (SDL_SCANCODE_LSHIFT < scancodeCount &&
+          keyboardState[SDL_SCANCODE_LSHIFT])
+      {
+        result |= KeyboardModifiers_Shift;
+      }
+
+      if (SDL_SCANCODE_RSHIFT < scancodeCount &&
+          keyboardState[SDL_SCANCODE_RSHIFT])
+      {
+        result |= KeyboardModifiers_Shift;
+      }
+
+      if (SDL_SCANCODE_LCTRL < scancodeCount &&
+          keyboardState[SDL_SCANCODE_LCTRL])
+      {
+        result |= KeyboardModifiers_Control;
+      }
+
+      if (SDL_SCANCODE_RCTRL < scancodeCount &&
+          keyboardState[SDL_SCANCODE_RCTRL])
+      {
+        result |= KeyboardModifiers_Control;
+      }
+
+      if (SDL_SCANCODE_LALT < scancodeCount &&
+          keyboardState[SDL_SCANCODE_LALT])
+      {
+        result |= KeyboardModifiers_Alt;
+      }
+
+      if (SDL_SCANCODE_RALT < scancodeCount &&
+          keyboardState[SDL_SCANCODE_RALT])
+      {
+        result |= KeyboardModifiers_Alt;
+      }
+    }
+
+    return static_cast<KeyboardModifiers>(result);
+  }
+
+
+  void SdlEngine::SetSize(unsigned int width,
+                          unsigned int height)
+  {
+    buffering_.SetSize(width, height, viewport_);
+    viewportChanged_ = true;
+    Refresh();
+  }
+
+
+  void SdlEngine::Stop()
+  {
+    if (continue_)
+    {
+      continue_ = false;
+      renderFrame_.Signal();  // Unlock the render thread
+      renderThread_.join();
+    }
+  }
+
+
+  void SdlEngine::Refresh()
+  {
+    renderFrame_.Signal();
+  }
+
+
+  SdlEngine::SdlEngine(SdlWindow& window,
+                       IViewport& viewport) :
+    window_(window),
+    viewport_(viewport),
+    continue_(true)
+  {
+    refreshEvent_ = SDL_RegisterEvents(1);
+
+    SetSize(window_.GetWidth(), window_.GetHeight());
+
+    viewport_.Register(*this);
+
+    renderThread_ = boost::thread(RenderThread, this);
+  }
+  
+
+  SdlEngine::~SdlEngine()
+  {
+    Stop();
+
+    viewport_.Unregister(*this);
+  }
+
+
+  void SdlEngine::Run()
+  {
+    int scancodeCount = 0;
+    const uint8_t* keyboardState = SDL_GetKeyboardState(&scancodeCount);
+
+    bool stop = false;
+    while (!stop)
+    {
+      Refresh();
+
+      SDL_Event event;
+
+      while (SDL_PollEvent(&event))
+      {
+        if (event.type == SDL_QUIT) 
+        {
+          stop = true;
+          break;
+        }
+        else if (event.type == refreshEvent_)
+        {
+          buffering_.SwapToScreen(window_);
+        }
+        else if (event.type == SDL_MOUSEBUTTONDOWN)
+        {
+          KeyboardModifiers modifiers = GetKeyboardModifiers(keyboardState, scancodeCount);
+
+          switch (event.button.button)
+          {
+            case SDL_BUTTON_LEFT:
+              viewport_.MouseDown(MouseButton_Left, event.button.x, event.button.y, modifiers);
+              break;
+            
+            case SDL_BUTTON_RIGHT:
+              viewport_.MouseDown(MouseButton_Right, event.button.x, event.button.y, modifiers);
+              break;
+            
+            case SDL_BUTTON_MIDDLE:
+              viewport_.MouseDown(MouseButton_Middle, event.button.x, event.button.y, modifiers);
+              break;
+
+            default:
+              break;
+          }
+        }
+        else if (event.type == SDL_MOUSEMOTION)
+        {
+          viewport_.MouseMove(event.button.x, event.button.y);
+        }
+        else if (event.type == SDL_MOUSEBUTTONUP)
+        {
+          viewport_.MouseUp();
+        }
+        else if (event.type == SDL_WINDOWEVENT)
+        {
+          switch (event.window.event)
+          {
+            case SDL_WINDOWEVENT_LEAVE:
+              viewport_.MouseLeave();
+              break;
+
+            case SDL_WINDOWEVENT_ENTER:
+              viewport_.MouseEnter();
+              break;
+
+            case SDL_WINDOWEVENT_SIZE_CHANGED:
+              SetSize(event.window.data1, event.window.data2);
+              break;
+
+            default:
+              break;
+          }
+        }
+        else if (event.type == SDL_MOUSEWHEEL)
+        {
+          KeyboardModifiers modifiers = GetKeyboardModifiers(keyboardState, scancodeCount);
+
+          int x, y;
+          SDL_GetMouseState(&x, &y);
+
+          if (event.wheel.y > 0)
+          {
+            viewport_.MouseWheel(MouseWheelDirection_Up, x, y, modifiers);
+          }
+          else if (event.wheel.y < 0)
+          {
+            viewport_.MouseWheel(MouseWheelDirection_Down, x, y, modifiers);
+          }
+        }
+        else if (event.type == SDL_KEYDOWN)
+        {
+          KeyboardModifiers modifiers = GetKeyboardModifiers(keyboardState, scancodeCount);
+
+          switch (event.key.keysym.sym)
+          {
+            case SDLK_a:  viewport_.KeyPressed('a', modifiers);  break;
+            case SDLK_b:  viewport_.KeyPressed('b', modifiers);  break;
+            case SDLK_c:  viewport_.KeyPressed('c', modifiers);  break;
+            case SDLK_d:  viewport_.KeyPressed('d', modifiers);  break;
+            case SDLK_e:  viewport_.KeyPressed('e', modifiers);  break;
+            case SDLK_f:  window_.ToggleMaximize();              break;
+            case SDLK_g:  viewport_.KeyPressed('g', modifiers);  break;
+            case SDLK_h:  viewport_.KeyPressed('h', modifiers);  break;
+            case SDLK_i:  viewport_.KeyPressed('i', modifiers);  break;
+            case SDLK_j:  viewport_.KeyPressed('j', modifiers);  break;
+            case SDLK_k:  viewport_.KeyPressed('k', modifiers);  break;
+            case SDLK_l:  viewport_.KeyPressed('l', modifiers);  break;
+            case SDLK_m:  viewport_.KeyPressed('m', modifiers);  break;
+            case SDLK_n:  viewport_.KeyPressed('n', modifiers);  break;
+            case SDLK_o:  viewport_.KeyPressed('o', modifiers);  break;
+            case SDLK_p:  viewport_.KeyPressed('p', modifiers);  break;
+            case SDLK_q:  stop = true;                           break;
+            case SDLK_r:  viewport_.KeyPressed('r', modifiers);  break;
+            case SDLK_s:  viewport_.KeyPressed('s', modifiers);  break;
+            case SDLK_t:  viewport_.KeyPressed('t', modifiers);  break;
+            case SDLK_u:  viewport_.KeyPressed('u', modifiers);  break;
+            case SDLK_v:  viewport_.KeyPressed('v', modifiers);  break;
+            case SDLK_w:  viewport_.KeyPressed('w', modifiers);  break;
+            case SDLK_x:  viewport_.KeyPressed('x', modifiers);  break;
+            case SDLK_y:  viewport_.KeyPressed('y', modifiers);  break;
+            case SDLK_z:  viewport_.KeyPressed('z', modifiers);  break;
+
+            default:
+              break;
+          }
+        }
+      }
+
+      SDL_Delay(10);   // Necessary for mouse wheel events to work
+    }
+
+    Stop();
+  }
+
+
+  void SdlEngine::GlobalInitialize()
+  {
+    SDL_Init(SDL_INIT_VIDEO);
+  }
+
+
+  void SdlEngine::GlobalFinalize()
+  {
+    SDL_Quit();
+  }
+}
+
+#endif