--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Applications/Generic/GuiAdapter.cpp	Mon Jun 24 14:35:00 2019 +0200
@@ -0,0 +1,799 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2019 Osimis S.A., 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 "GuiAdapter.h"
+
+#if ORTHANC_ENABLE_OPENGL == 1
+#  include "../../Framework/OpenGL/OpenGLIncludes.h"
+#endif
+
+#if ORTHANC_ENABLE_SDL == 1
+#  include <SDL_video.h>
+#  include <SDL_render.h>
+#  include <SDL.h>
+#endif
+
+#if ORTHANC_ENABLE_THREADS == 1
+#  include "../../Framework/Messages/LockingEmitter.h"
+#endif
+
+namespace OrthancStone
+{
+  void GuiAdapter::RegisterWidget(boost::shared_ptr<IGuiAdapterWidget> widget)
+  {
+    widgets_.push_back(widget);
+  }
+
+  std::ostream& operator<<(
+    std::ostream& os, const GuiAdapterKeyboardEvent& event)
+  {
+    os << "ctrl: " << event.ctrlKey << ", " <<
+      "shift: " << event.shiftKey << ", " <<
+      "alt: " << event.altKey;
+    return os;
+  }
+
+#if ORTHANC_ENABLE_WASM == 1
+  void GuiAdapter::Run()
+  {
+  }
+
+  void ConvertFromPlatform(
+    GuiAdapterUiEvent& dest,
+    int                      eventType,
+    const EmscriptenUiEvent& src)
+  {
+    // no data for now
+  }
+
+  void ConvertFromPlatform(
+    GuiAdapterMouseEvent& dest,
+    int                         eventType,
+    const EmscriptenMouseEvent& src)
+  {
+    memset(&dest, 0, sizeof(GuiAdapterMouseEvent));
+    switch (eventType)
+    {
+    case EMSCRIPTEN_EVENT_CLICK:
+      LOG(ERROR) << "Emscripten EMSCRIPTEN_EVENT_CLICK is not supported";
+      ORTHANC_ASSERT(false, "Not supported");
+      break;
+    case EMSCRIPTEN_EVENT_MOUSEDOWN:
+      dest.type = GUIADAPTER_EVENT_MOUSEDOWN;
+      break;
+    case EMSCRIPTEN_EVENT_MOUSEMOVE:
+      dest.type = GUIADAPTER_EVENT_MOUSEMOVE;
+      break;
+    case EMSCRIPTEN_EVENT_MOUSEUP:
+      dest.type = GUIADAPTER_EVENT_MOUSEUP;
+      break;
+    case EMSCRIPTEN_EVENT_WHEEL:
+      dest.type = GUIADAPTER_EVENT_WHEEL;
+      break;
+
+    default:
+      LOG(ERROR) << "Emscripten event: " << eventType << " is not supported";
+      ORTHANC_ASSERT(false, "Not supported");
+    }
+    //dest.timestamp = src.timestamp;
+    //dest.screenX = src.screenX;
+    //dest.screenY = src.screenY;
+    //dest.clientX = src.clientX;
+    //dest.clientY = src.clientY;
+    dest.ctrlKey = src.ctrlKey;
+    dest.shiftKey = src.shiftKey;
+    dest.altKey = src.altKey;
+    //dest.metaKey = src.metaKey;
+    dest.button = src.button;
+    //dest.buttons = src.buttons;
+    //dest.movementX = src.movementX;
+    //dest.movementY = src.movementY;
+    dest.targetX = src.targetX;
+    dest.targetY = src.targetY;
+    //dest.canvasX = src.canvasX;
+    //dest.canvasY = src.canvasY;
+    //dest.padding = src.padding;
+  }
+
+  void ConvertFromPlatform(
+    GuiAdapterWheelEvent& dest,
+    int                         eventType,
+    const EmscriptenWheelEvent& src)
+  {
+    ConvertFromPlatform(dest.mouse, eventType, src.mouse);
+    dest.deltaX = src.deltaX;
+    dest.deltaY = src.deltaY;
+    switch (src.deltaMode)
+    {
+    case DOM_DELTA_PIXEL:
+      dest.deltaMode = GUIADAPTER_DELTA_PIXEL;
+      break;
+    case DOM_DELTA_LINE:
+      dest.deltaMode = GUIADAPTER_DELTA_LINE;
+      break;
+    case DOM_DELTA_PAGE:
+      dest.deltaMode = GUIADAPTER_DELTA_PAGE;
+      break;
+    default:
+      ORTHANC_ASSERT(false, "Unknown deltaMode: " << src.deltaMode <<
+        " in wheel event...");
+    }
+    dest.deltaMode = src.deltaMode;
+  }
+
+  void ConvertFromPlatform(
+    GuiAdapterKeyboardEvent& dest,
+    const EmscriptenKeyboardEvent& src)
+  {
+    dest.ctrlKey = src.ctrlKey;
+    dest.shiftKey = src.shiftKey;
+    dest.altKey = src.altKey;
+  }
+   
+  template<typename GenericFunc>
+  struct FuncAdapterPayload
+  {
+    std::string canvasId;
+    void* userData;
+    GenericFunc callback;
+  };
+
+  template<typename GenericFunc,
+           typename GuiAdapterEvent,
+           typename EmscriptenEvent>
+  EM_BOOL OnEventAdapterFunc(
+    int eventType, const EmscriptenEvent* emEvent, void* userData)
+  {
+
+    // userData is OnMouseWheelFuncAdapterPayload
+    FuncAdapterPayload<GenericFunc>* payload =
+      reinterpret_cast<FuncAdapterPayload<GenericFunc>*>(userData);
+    // LOG(INFO) << "OnEventAdapterFunc";
+    // LOG(INFO) << "------------------";
+    // LOG(INFO) << "eventType: " << eventType << " wheelEvent: " << 
+    //   (int)wheelEvent << " userData: " << userData << 
+    //   " payload->userData: " << payload->userData;
+    
+    GuiAdapterEvent guiEvent;
+    ConvertFromPlatform(guiEvent, eventType, *emEvent);
+    bool ret = (*(payload->callback))(payload->canvasId, &guiEvent, payload->userData);
+    return static_cast<EM_BOOL>(ret);
+  }
+
+  template<typename GenericFunc,
+    typename GuiAdapterEvent,
+    typename EmscriptenEvent>
+    EM_BOOL OnEventAdapterFunc2(
+      int /*eventType*/, const EmscriptenEvent* wheelEvent, void* userData)
+  {
+    // userData is OnMouseWheelFuncAdapterPayload
+    FuncAdapterPayload<GenericFunc>* payload =
+      reinterpret_cast<FuncAdapterPayload<GenericFunc>*>(userData);
+    
+    GuiAdapterEvent guiEvent;
+    ConvertFromPlatform(guiEvent, *wheelEvent);
+    bool ret = (*(payload->callback))(payload->canvasId, &guiEvent, payload->userData);
+    return static_cast<EM_BOOL>(ret);
+  }
+
+  template<typename GenericFunc>
+    EM_BOOL OnEventAdapterFunc3(
+      double time, void* userData)
+  {
+    // userData is OnMouseWheelFuncAdapterPayload
+    FuncAdapterPayload<GenericFunc>* payload =
+      reinterpret_cast<FuncAdapterPayload<GenericFunc>*>(userData);
+    //std::auto_ptr< FuncAdapterPayload<GenericFunc> > deleter(payload);
+    bool ret = (*(payload->callback))(time, payload->userData);
+    return static_cast<EM_BOOL>(ret);
+  }
+
+  // resize: (const char* target, void* userData, EM_BOOL useCapture, em_ui_callback_func callback)
+  template<
+    typename GenericFunc, 
+    typename GuiAdapterEvent, 
+    typename EmscriptenEvent, 
+    typename EmscriptenSetCallbackFunc>
+  static void SetCallback(
+    EmscriptenSetCallbackFunc emFunc, 
+    std::string canvasId, void* userData, bool capture, GenericFunc func)
+  {
+    // TODO: write RemoveCallback with an int id that gets returned from
+    // here
+    FuncAdapterPayload<GenericFunc>* payload = 
+      new FuncAdapterPayload<GenericFunc>();
+    std::auto_ptr<FuncAdapterPayload<GenericFunc> > payloadP(payload);
+    payload->canvasId = canvasId;
+    payload->callback = func;
+    payload->userData = userData;
+    void* userDataRaw = reinterpret_cast<void*>(payload);
+    // LOG(INFO) << "SetCallback -- userDataRaw: " << userDataRaw <<
+    //   " payload: " << payload << " payload->userData: " << payload->userData;
+    (*emFunc)(
+      canvasId.c_str(),
+      userDataRaw,
+      static_cast<EM_BOOL>(capture),
+      &OnEventAdapterFunc<GenericFunc, GuiAdapterEvent, EmscriptenEvent>,
+      EM_CALLBACK_THREAD_CONTEXT_CALLING_THREAD);
+    payloadP.release();
+  }
+
+  template<
+    typename GenericFunc,
+    typename GuiAdapterEvent,
+    typename EmscriptenEvent,
+    typename EmscriptenSetCallbackFunc>
+    static void SetCallback2(
+      EmscriptenSetCallbackFunc emFunc,
+      std::string canvasId, void* userData, bool capture, GenericFunc func)
+  {
+    std::auto_ptr<FuncAdapterPayload<GenericFunc> > payload(
+      new FuncAdapterPayload<GenericFunc>()
+    );
+    payload->canvasId = canvasId;
+    payload->callback = func;
+    payload->userData = userData;
+    void* userDataRaw = reinterpret_cast<void*>(payload.release());
+    (*emFunc)(
+      canvasId.c_str(),
+      userDataRaw,
+      static_cast<EM_BOOL>(capture),
+      &OnEventAdapterFunc2<GenericFunc, GuiAdapterEvent, EmscriptenEvent>,
+      EM_CALLBACK_THREAD_CONTEXT_CALLING_THREAD);
+  }
+
+  template<
+    typename GenericFunc,
+    typename EmscriptenSetCallbackFunc>
+    static void SetAnimationFrameCallback(
+      EmscriptenSetCallbackFunc emFunc,
+      void* userData, GenericFunc func)
+  {
+    // LOG(ERROR) << "SetAnimationFrameCallback !!!!!! (RequestAnimationFrame)";
+    std::auto_ptr<FuncAdapterPayload<GenericFunc> > payload(
+      new FuncAdapterPayload<GenericFunc>()
+    );
+    payload->canvasId = "UNDEFINED";
+    payload->callback = func;
+    payload->userData = userData;
+    void* userDataRaw = reinterpret_cast<void*>(payload.release());
+    (*emFunc)(
+      &OnEventAdapterFunc3<GenericFunc>,
+      userDataRaw);
+  }
+
+  void GuiAdapter::SetWheelCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseWheelFunc func)
+  {
+    SetCallback<OnMouseWheelFunc, GuiAdapterWheelEvent, EmscriptenWheelEvent>(
+      &emscripten_set_wheel_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetMouseDownCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+  {
+    SetCallback<OnMouseEventFunc, GuiAdapterMouseEvent, EmscriptenMouseEvent>(
+      &emscripten_set_mousedown_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetMouseMoveCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+  {
+    // LOG(INFO) << "SetMouseMoveCallback -- " << "supplied userData: " << 
+    //   userData;
+
+    SetCallback<OnMouseEventFunc, GuiAdapterMouseEvent, EmscriptenMouseEvent>(
+      &emscripten_set_mousemove_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetMouseUpCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+  {
+    SetCallback<OnMouseEventFunc, GuiAdapterMouseEvent, EmscriptenMouseEvent>(
+      &emscripten_set_mouseup_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetKeyDownCallback(
+    std::string canvasId, void* userData, bool capture, OnKeyDownFunc func)
+  {
+    SetCallback2<OnKeyDownFunc, GuiAdapterKeyboardEvent, EmscriptenKeyboardEvent>(
+      &emscripten_set_keydown_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetKeyUpCallback(
+    std::string canvasId, void* userData, bool capture, OnKeyUpFunc func)
+  {
+    SetCallback2<OnKeyUpFunc, GuiAdapterKeyboardEvent, EmscriptenKeyboardEvent>(
+      &emscripten_set_keyup_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::SetResizeCallback(
+    std::string canvasId, void* userData, bool capture, OnWindowResizeFunc func)
+  {
+    SetCallback<OnWindowResizeFunc, GuiAdapterUiEvent, EmscriptenUiEvent>(
+      &emscripten_set_resize_callback_on_thread,
+      canvasId,
+      userData,
+      capture,
+      func);
+  }
+
+  void GuiAdapter::RequestAnimationFrame(
+    OnAnimationFrameFunc func, void* userData)
+  {
+    // LOG(ERROR) << "-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+";
+    // LOG(ERROR) << "RequestAnimationFrame";
+    // LOG(ERROR) << "-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+";
+    SetAnimationFrameCallback<OnAnimationFrameFunc>(
+      &emscripten_request_animation_frame_loop,
+      userData,
+      func);
+  }
+
+#if 0
+  void GuiAdapter::SetKeyDownCallback(
+    std::string canvasId, void* userData, bool capture, OnKeyDownFunc func)
+  {
+    emscripten_set_keydown_callback(canvasId.c_str(), userData, static_cast<EM_BOOL>(capture), func);
+  }
+  void GuiAdapter::SetKeyUpCallback(
+    std::string canvasId, void* userData, bool capture, OnKeyUpFunc func)
+  {
+    emscripten_set_keyup_callback(canvasId.c_str(), userData, static_cast<EM_BOOL>(capture), func);
+  }
+
+  void GuiAdapter::SetResizeCallback(std::string canvasId, void* userData, bool capture, OnWindowResizeFunc func)
+  {
+    emscripten_set_resize_callback(canvasId.c_str(), userData, static_cast<EM_BOOL>(capture), func);
+  }
+
+  void GuiAdapter::RequestAnimationFrame(OnAnimationFrameFunc func, void* userData)
+  {
+    emscripten_request_animation_frame_loop(func, userData);
+  }
+#endif
+
+
+#else
+
+// SDL ONLY
+void ConvertFromPlatform(
+  GuiAdapterMouseEvent& dest,
+  bool ctrlPressed, bool shiftPressed, bool altPressed,
+  const SDL_Event& source)
+{
+  memset(&dest, 0, sizeof(GuiAdapterMouseEvent));
+  switch (source.type)
+  {
+  case SDL_MOUSEBUTTONDOWN:
+    dest.type = GUIADAPTER_EVENT_MOUSEDOWN;
+    break;
+  case SDL_MOUSEMOTION:
+    dest.type = GUIADAPTER_EVENT_MOUSEMOVE;
+    break;
+  case SDL_MOUSEBUTTONUP:
+    dest.type = GUIADAPTER_EVENT_MOUSEUP;
+    break;
+  case SDL_MOUSEWHEEL:
+    dest.type = GUIADAPTER_EVENT_WHEEL;
+    break;
+  default:
+    LOG(ERROR) << "SDL event: " << source.type << " is not supported";
+    ORTHANC_ASSERT(false, "Not supported");
+    }
+  //dest.timestamp = src.timestamp;
+  //dest.screenX = src.screenX;
+  //dest.screenY = src.screenY;
+  //dest.clientX = src.clientX;
+  //dest.clientY = src.clientY;
+  dest.ctrlKey = ctrlPressed;
+  dest.shiftKey = shiftPressed;
+  dest.altKey = altPressed;
+  //dest.metaKey = src.metaKey;
+  switch (source.button.button)
+  {
+  case SDL_BUTTON_MIDDLE:
+    dest.button = 1;
+    break;
+
+  case SDL_BUTTON_RIGHT:
+    dest.button = 2;
+    break;
+
+  case SDL_BUTTON_LEFT:
+    dest.button = 0;
+    break;
+
+  default:
+    break;
+  }
+  //dest.buttons = src.buttons;
+  //dest.movementX = src.movementX;
+  //dest.movementY = src.movementY;
+  dest.targetX = source.button.x;
+  dest.targetY = source.button.y;
+  //dest.canvasX = src.canvasX;
+  //dest.canvasY = src.canvasY;
+  //dest.padding = src.padding;
+  }
+
+void ConvertFromPlatform(
+  GuiAdapterWheelEvent& dest,
+  bool ctrlPressed, bool shiftPressed, bool altPressed,
+  const SDL_Event& source)
+{
+  ConvertFromPlatform(dest.mouse, ctrlPressed, shiftPressed, altPressed, source);
+  dest.deltaX = source.wheel.x;
+  dest.deltaY = source.wheel.y;
+}
+
+
+
+  // SDL ONLY
+  void GuiAdapter::SetResizeCallback(
+    std::string canvasId, void* userData, bool capture, OnWindowResizeFunc func)
+  {
+    resizeHandlers_.push_back(EventHandlerData<OnWindowResizeFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetMouseDownCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+ {
+    mouseDownHandlers_.push_back(EventHandlerData<OnMouseEventFunc>(canvasId, func, userData));
+ }
+
+  // SDL ONLY
+  void GuiAdapter::SetMouseMoveCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc  func)
+ {
+    mouseMoveHandlers_.push_back(EventHandlerData<OnMouseEventFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetMouseUpCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc  func)
+ {
+    mouseUpHandlers_.push_back(EventHandlerData<OnMouseEventFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetWheelCallback(
+   std::string canvasId, void* userData, bool capture, OnMouseWheelFunc  func)
+  {
+    mouseWheelHandlers_.push_back(EventHandlerData<OnMouseWheelFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetKeyDownCallback(
+   std::string canvasId, void* userData, bool capture, OnKeyDownFunc   func)
+ {
+ }
+
+  // SDL ONLY
+  void GuiAdapter::SetKeyUpCallback(
+   std::string canvasId, void* userData, bool capture, OnKeyUpFunc    func)
+ {
+ }
+
+
+  // SDL ONLY
+  void GuiAdapter::OnAnimationFrame()
+  {
+    for (size_t i = 0; i < animationFrameHandlers_.size(); i++)
+    {
+      // TODO: fix time 
+      (*(animationFrameHandlers_[i].first))(0, animationFrameHandlers_[i].second);
+    }
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnResize()
+  {
+    for (size_t i = 0; i < resizeHandlers_.size(); i++)
+    {
+      (*(resizeHandlers_[i].func))(
+        resizeHandlers_[i].canvasName, 0, resizeHandlers_[i].userData);
+    }
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnMouseWheelEvent(uint32_t windowID, const GuiAdapterWheelEvent& event)
+  {
+
+    // the SDL window name IS the canvas name ("canvas" is used because this lib
+    // is designed for Wasm
+    SDL_Window* sdlWindow = SDL_GetWindowFromID(windowID);
+    ORTHANC_ASSERT(sdlWindow != NULL, "Window ID \"" << windowID << "\" is not a valid SDL window ID!");
+
+    const char* windowTitleSz = SDL_GetWindowTitle(sdlWindow);
+    ORTHANC_ASSERT(windowTitleSz != NULL, "Window ID \"" << windowID << "\" has a NULL window title!");
+
+    std::string windowTitle(windowTitleSz);
+    ORTHANC_ASSERT(windowTitle != "", "Window ID \"" << windowID << "\" has an empty window title!");
+
+    switch (event.mouse.type)
+    {
+    case GUIADAPTER_EVENT_WHEEL:
+      for (size_t i = 0; i < mouseWheelHandlers_.size(); i++)
+      {
+        if(mouseWheelHandlers_[i].canvasName == windowTitle)
+          (*(mouseWheelHandlers_[i].func))(windowTitle, &event, mouseWheelHandlers_[i].userData);
+      }
+      break;
+    default:
+      ORTHANC_ASSERT(false, "Wrong event.type: " << event.mouse.type << " in GuiAdapter::OnMouseWheelEvent(...)");
+      break;
+    }
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnMouseEvent(uint32_t windowID, const GuiAdapterMouseEvent& event)
+  {
+    // the SDL window name IS the canvas name ("canvas" is used because this lib
+    // is designed for Wasm
+    SDL_Window* sdlWindow = SDL_GetWindowFromID(windowID);
+    ORTHANC_ASSERT(sdlWindow != NULL, "Window ID \"" << windowID << "\" is not a valid SDL window ID!");
+     
+    const char* windowTitleSz = SDL_GetWindowTitle(sdlWindow);
+    ORTHANC_ASSERT(windowTitleSz != NULL, "Window ID \"" << windowID << "\" has a NULL window title!");
+
+    std::string windowTitle(windowTitleSz);
+    ORTHANC_ASSERT(windowTitle != "", "Window ID \"" << windowID << "\" has an empty window title!");
+
+    switch (event.type)
+    {
+    case GUIADAPTER_EVENT_MOUSEDOWN:
+      for (size_t i = 0; i < mouseDownHandlers_.size(); i++)
+      {
+        if (mouseDownHandlers_[i].canvasName == windowTitle)
+          (*(mouseDownHandlers_[i].func))(windowTitle, &event, mouseDownHandlers_[i].userData);
+      }
+      break;
+    case GUIADAPTER_EVENT_MOUSEMOVE:
+      for (size_t i = 0; i < mouseMoveHandlers_.size(); i++)
+      {
+        if (mouseMoveHandlers_[i].canvasName == windowTitle)
+          (*(mouseMoveHandlers_[i].func))(windowTitle, &event, mouseMoveHandlers_[i].userData);
+      }
+      break;
+    case GUIADAPTER_EVENT_MOUSEUP:
+      for (size_t i = 0; i < mouseUpHandlers_.size(); i++)
+      {
+        if (mouseUpHandlers_[i].canvasName == windowTitle)
+          (*(mouseUpHandlers_[i].func))(windowTitle, &event, mouseUpHandlers_[i].userData);
+      }
+      break;
+    default:
+      ORTHANC_ASSERT(false, "Wrong event.type: " << event.type << " in GuiAdapter::OnMouseEvent(...)");
+      break;
+    }
+
+    ////boost::shared_ptr<IGuiAdapterWidget> GetWidgetFromWindowId();
+    //boost::shared_ptr<IGuiAdapterWidget> foundWidget;
+    //VisitWidgets([foundWidget, windowID](auto widget)
+    //  {
+    //    if (widget->GetSdlWindowID() == windowID)
+    //      foundWidget = widget;
+    //  });
+    //ORTHANC_ASSERT(foundWidget, "WindowID " << windowID << " was not found in the registered widgets!");
+    //if(foundWidget)
+    //  foundWidget->
+  }
+
+  // SDL ONLY
+  void GuiAdapter::RequestAnimationFrame(OnAnimationFrameFunc func, void* userData)
+  {
+    animationFrameHandlers_.push_back(std::make_pair(func, userData));
+  }
+
+# if ORTHANC_ENABLE_OPENGL == 1 && !defined(__APPLE__)   /* OpenGL debug is not available on OS X */
+
+  // SDL ONLY
+  static void GLAPIENTRY
+    OpenGLMessageCallback(GLenum source,
+      GLenum type,
+      GLuint id,
+      GLenum severity,
+      GLsizei length,
+      const GLchar* message,
+      const void* userParam)
+  {
+    if (severity != GL_DEBUG_SEVERITY_NOTIFICATION)
+    {
+      fprintf(stderr, "GL CALLBACK: %s type = 0x%x, severity = 0x%x, message = %s\n",
+        (type == GL_DEBUG_TYPE_ERROR ? "** GL ERROR **" : ""),
+        type, severity, message);
+    }
+}
+# endif
+
+  // SDL ONLY
+  void GuiAdapter::Run()
+  {
+# if ORTHANC_ENABLE_OPENGL == 1 && !defined(__APPLE__)
+    glEnable(GL_DEBUG_OUTPUT);
+    glDebugMessageCallback(OpenGLMessageCallback, 0);
+# endif
+
+    // Uint32 SDL_GetWindowID(SDL_Window* window)
+    // SDL_Window* SDL_GetWindowFromID(Uint32 id)   // may return NULL
+
+    bool stop = false;
+    while (!stop)
+    {
+      {
+        LockingEmitter::WriterLock lock(lockingEmitter_);
+        OnAnimationFrame(); // in SDL we must call it
+      }
+
+      SDL_Event event;
+
+      while (!stop && SDL_PollEvent(&event))
+      {
+        LockingEmitter::WriterLock lock(lockingEmitter_);
+
+        if (event.type == SDL_QUIT)
+        {
+          // TODO: call exit callbacks here
+          stop = true;
+          break;
+        }
+        else if ( (event.type == SDL_MOUSEMOTION) ||
+                  (event.type == SDL_MOUSEBUTTONDOWN) ||
+                  (event.type == SDL_MOUSEBUTTONUP) )
+        {
+          int scancodeCount = 0;
+          const uint8_t* keyboardState = SDL_GetKeyboardState(&scancodeCount);
+          bool ctrlPressed(false);
+          bool shiftPressed(false);
+          bool altPressed(false);
+            
+          if (SDL_SCANCODE_LCTRL < scancodeCount && keyboardState[SDL_SCANCODE_LCTRL])
+            ctrlPressed = true;
+          if (SDL_SCANCODE_RCTRL < scancodeCount && keyboardState[SDL_SCANCODE_RCTRL])
+            ctrlPressed = true;
+          if (SDL_SCANCODE_LSHIFT < scancodeCount && keyboardState[SDL_SCANCODE_LSHIFT])
+            shiftPressed = true;
+          if (SDL_SCANCODE_RSHIFT < scancodeCount && keyboardState[SDL_SCANCODE_RSHIFT])
+            shiftPressed = true;
+          if (SDL_SCANCODE_LALT < scancodeCount && keyboardState[SDL_SCANCODE_LALT])
+            altPressed = true;
+          
+          GuiAdapterMouseEvent dest;
+          ConvertFromPlatform(dest, ctrlPressed, shiftPressed, altPressed, event);
+          OnMouseEvent(event.window.windowID, dest);
+#if 0
+          // for reference, how to create trackers
+          if (tracker)
+          {
+            PointerEvent e;
+            e.AddPosition(compositor.GetPixelCenterCoordinates(
+              event.button.x, event.button.y));
+            tracker->PointerMove(e);
+          }
+#endif
+        }
+        else if (event.type == SDL_MOUSEWHEEL)
+        {
+
+          int scancodeCount = 0;
+          const uint8_t* keyboardState = SDL_GetKeyboardState(&scancodeCount);
+          bool ctrlPressed(false);
+          bool shiftPressed(false);
+          bool altPressed(false);
+
+          if (SDL_SCANCODE_LCTRL < scancodeCount && keyboardState[SDL_SCANCODE_LCTRL])
+            ctrlPressed = true;
+          if (SDL_SCANCODE_RCTRL < scancodeCount && keyboardState[SDL_SCANCODE_RCTRL])
+            ctrlPressed = true;
+          if (SDL_SCANCODE_LSHIFT < scancodeCount && keyboardState[SDL_SCANCODE_LSHIFT])
+            shiftPressed = true;
+          if (SDL_SCANCODE_RSHIFT < scancodeCount && keyboardState[SDL_SCANCODE_RSHIFT])
+            shiftPressed = true;
+          if (SDL_SCANCODE_LALT < scancodeCount && keyboardState[SDL_SCANCODE_LALT])
+            altPressed = true;
+
+          GuiAdapterWheelEvent dest;
+          ConvertFromPlatform(dest, ctrlPressed, shiftPressed, altPressed, event);
+          OnMouseWheelEvent(event.window.windowID, dest);
+
+          //KeyboardModifiers modifiers = GetKeyboardModifiers(keyboardState, scancodeCount);
+
+          //int x, y;
+          //SDL_GetMouseState(&x, &y);
+
+          //if (event.wheel.y > 0)
+          //{
+          //  locker.GetCentralViewport().MouseWheel(MouseWheelDirection_Up, x, y, modifiers);
+          //}
+          //else if (event.wheel.y < 0)
+          //{
+          //  locker.GetCentralViewport().MouseWheel(MouseWheelDirection_Down, x, y, modifiers);
+          //}
+        }
+        else if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED)
+        {
+#if 0
+          tracker.reset();
+#endif
+          OnResize();
+        }
+        else if (event.type == SDL_KEYDOWN && event.key.repeat == 0 /* Ignore key bounce */)
+        {
+          switch (event.key.keysym.sym)
+          {
+          case SDLK_f:
+            // window.GetWindow().ToggleMaximize(); //TODO: move to particular handler
+            break;
+
+          case SDLK_s:
+#if 0
+            // TODO: re-enable at application-level!!!!
+            VisitWidgets(
+              [](auto value)
+              {
+                auto widget = boost::dynamic_pointer_cast<VolumeSlicerWidget()
+                value->FitContent();
+              });
+#endif
+            break;
+
+          case SDLK_q:
+            stop = true;
+            break;
+
+          default:
+            break;
+          }
+        }
+        //        HandleApplicationEvent(controller, compositor, event, tracker);
+      }
+
+      SDL_Delay(1);
+    }
+  }
+#endif
+}
+