--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Deprecated/Applications/Generic/GuiAdapter.cpp	Wed Apr 29 20:44:31 2020 +0200
@@ -0,0 +1,1142 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 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/Deprecated/Messages/LockingEmitter.h"
+#endif
+
+#include <Core/Compatibility.h>
+
+namespace OrthancStone
+{
+  std::ostream& operator<<(
+    std::ostream& os, const GuiAdapterKeyboardEvent& event)
+  {
+    os << "sym: " << event.sym << " (" << (int)(event.sym[0]) << ") ctrl: " << event.ctrlKey << ", " <<
+      "shift: " << event.shiftKey << ", " <<
+      "alt: " << event.altKey;
+    return os;
+  }
+
+  std::ostream& operator<<(
+    std::ostream& os, const GuiAdapterMouseEvent& event)
+  {
+    os << "targetX: " << event.targetX << " targetY: " << event.targetY << " button: " << event.button
+      << "ctrlKey: " << event.ctrlKey << "shiftKey: " << event.shiftKey << "altKey: " << event.altKey;
+      
+    return os;
+  }
+
+#if ORTHANC_ENABLE_WASM == 1
+  void GuiAdapter::Run(GuiAdapterRunFunc /*func*/, void* /*cookie*/)
+  {
+  }
+
+  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_DBLCLICK:
+      dest.type = GUIADAPTER_EVENT_MOUSEDBLCLICK;
+      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.sym[0] = src.key[0];
+    dest.sym[1] = 0;
+    dest.ctrlKey = src.ctrlKey;
+    dest.shiftKey = src.shiftKey;
+    dest.altKey = src.altKey;
+  }
+
+  template<typename GenericFunc>
+  struct FuncAdapterPayload
+  {
+    std::string canvasCssSelector;
+    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->canvasCssSelector, &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->canvasCssSelector, &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::unique_ptr< FuncAdapterPayload<GenericFunc> > deleter(payload);
+    bool ret = (*(payload->callback))(time, payload->userData);
+    return static_cast<EM_BOOL>(ret);
+  }
+
+  /*
+  
+  Explanation
+  ===========
+
+  - in "older" Emscripten, where DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR doesn't exist or is set to 0,
+    the following strings need to be used to register events:
+    - for canvas, the canvas DOM id. In case of <canvas id="mycanvas1" width='640' ...></canvas>", the string needs 
+      to be "mycanvas"
+    - for the window (for key events), the string needs to be "#window"
+  - in newer Emscripten where DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR==1 (or maybe is not there anymore, in the
+    future as of 2020-04-20)
+    - for canvas, the canvas DOM id. In case of <canvas id="mycanvas1" width='640' ...></canvas>", the string needs
+      to be "#mycanvas"  (notice the "number sign", aka "hash", NOT AKA "sharp", as can be read on https://en.wikipedia.org/wiki/Number_sign)
+    - for the window (for key events), the string needs to be EMSCRIPTEN_EVENT_TARGET_WINDOW. I do not mean 
+      "EMSCRIPTEN_EVENT_TARGET_WINDOW", but the #define EMSCRIPTEN_EVENT_TARGET_WINDOW         ((const char*)2) that
+      can be found in emscripten/html5.h
+
+  The code below converts the input canvasId (as in the old emscripten) to the emscripten-compliant one, with the
+  following compile condition : #if DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR == 1
+
+  If the DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR build parameter disappears, you might want to refactor this code
+  or continue to pass the DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR compile macro (which is different from the CMake
+  variable)     
+
+  What we are doing below:
+  - in older Emscripten, the registration functions will receive "mycanvas" and "#window" and the callbacks will receive 
+    the same std::string in their payload ("mycanvas" and "#window")
+
+  - in newer Emscripten, the registration functions will receive "#mycanvas" and EMSCRIPTEN_EVENT_TARGET_WINDOW, but 
+    the callbacks will receive "#mycanvas" and "#window" (since it is not possible to store the EMSCRIPTEN_EVENT_TARGET_WINDOW
+    magic value in an std::string, while we still want the callback to be able to change its behavior according to the
+    target element.
+  
+  */
+
+  void convertElementTarget(const char*& outCanvasCssSelectorSz, std::string& outCanvasCssSelector, const std::string& canvasId)
+  {
+    // only "#window" can start with a #
+    if (canvasId[0] == '#')
+    {
+      ORTHANC_ASSERT(canvasId == "#window");
+    }
+#if DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR == 1
+    if (canvasId == "#window")
+    {
+      // we store this in the payload so that the callback can 
+      outCanvasCssSelector = "#window";
+      outCanvasCssSelectorSz = EMSCRIPTEN_EVENT_TARGET_WINDOW;
+    }
+    else
+    {
+      outCanvasCssSelector = "#" + canvasId;
+      outCanvasCssSelectorSz = outCanvasCssSelector.c_str();
+    }
+#else
+    if (canvasId == "#window")
+    {
+      // we store this in the payload so that the callback can 
+      outCanvasCssSelector = "#window";
+      outCanvasCssSelectorSz = outCanvasCssSelector.c_str();;
+    }
+    else
+    {
+      outCanvasCssSelector = canvasId;
+      outCanvasCssSelectorSz = outCanvasCssSelector.c_str();;
+    }
+#endif
+  }
+
+  // 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)
+  {
+    std::string canvasCssSelector;
+    const char* canvasCssSelectorSz = NULL;
+    convertElementTarget(canvasCssSelectorSz, canvasCssSelector, canvasId);
+
+    // TODO: write RemoveCallback with an int id that gets returned from here
+
+    // create userdata payload
+    std::unique_ptr<FuncAdapterPayload<GenericFunc> > payload(new FuncAdapterPayload<GenericFunc>());
+    payload->canvasCssSelector = canvasCssSelector;
+    payload->callback = func;
+    payload->userData = userData;
+    void* userDataRaw = reinterpret_cast<void*>(payload.release());
+
+    // call the registration function
+    (*emFunc)(
+      canvasCssSelectorSz,
+      userDataRaw,
+      static_cast<EM_BOOL>(capture),
+      &OnEventAdapterFunc<GenericFunc, GuiAdapterEvent, EmscriptenEvent>,
+      EM_CALLBACK_THREAD_CONTEXT_CALLING_THREAD);
+  }
+
+  template<
+    typename GenericFunc,
+    typename GuiAdapterEvent,
+    typename EmscriptenEvent,
+    typename EmscriptenSetCallbackFunc>
+    static void SetCallback2(
+      EmscriptenSetCallbackFunc emFunc,
+      std::string canvasId, void* userData, bool capture, GenericFunc func)
+  {
+    std::string canvasCssSelector;
+    const char* canvasCssSelectorSz = NULL;
+    convertElementTarget(canvasCssSelectorSz, canvasCssSelector, canvasId);
+
+    // TODO: write RemoveCallback with an int id that gets returned from here
+
+    // create userdata payload
+    std::unique_ptr<FuncAdapterPayload<GenericFunc> > payload(new FuncAdapterPayload<GenericFunc>());
+    payload->canvasCssSelector = canvasCssSelector;
+    payload->callback = func;
+    payload->userData = userData;
+    void* userDataRaw = reinterpret_cast<void*>(payload.release());
+
+    // call the registration function
+    (*emFunc)(
+      canvasCssSelectorSz,
+      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)
+  {
+    std::unique_ptr<FuncAdapterPayload<GenericFunc> > payload(
+      new FuncAdapterPayload<GenericFunc>()
+    );
+    payload->canvasCssSelector = "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::SetMouseDblClickCallback(
+      std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+  {
+    SetCallback<OnMouseEventFunc, GuiAdapterMouseEvent, EmscriptenMouseEvent>(
+      &emscripten_set_dblclick_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);
+  }
+
+#if 0
+  // useless under Wasm where canvas resize is handled automatically
+  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);
+  }
+#endif
+
+  void GuiAdapter::RequestAnimationFrame(
+    OnAnimationFrameFunc func, void* userData)
+  {
+    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);
+  }
+
+  // handled from within WebAssemblyViewport
+  //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:
+      if (source.button.clicks == 1) {
+        dest.type = GUIADAPTER_EVENT_MOUSEDOWN;
+      } else if (source.button.clicks == 2) {
+        dest.type = GUIADAPTER_EVENT_MOUSEDBLCLICK;
+      } else {
+        dest.type = GUIADAPTER_EVENT_MOUSEDBLCLICK;
+        LOG(WARNING) << "Multiple-click ignored.";
+      }
+      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 =GUIADAPTER_MOUSEBUTTON_MIDDLE;
+      break;
+
+    case SDL_BUTTON_RIGHT:
+      dest.button = GUIADAPTER_MOUSEBUTTON_RIGHT;
+      break;
+
+    case SDL_BUTTON_LEFT:
+      dest.button = GUIADAPTER_MOUSEBUTTON_LEFT;
+      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;
+  }
+
+  void ConvertFromPlatform(GuiAdapterKeyboardEvent& dest, const SDL_Event& src)
+  {
+    memset(&dest, 0, sizeof(GuiAdapterMouseEvent));
+    switch (src.type)
+    {
+    case SDL_KEYDOWN:
+      dest.type = GUIADAPTER_EVENT_KEYDOWN;
+      break;
+    case SDL_KEYUP:
+      dest.type = GUIADAPTER_EVENT_KEYUP;
+      break;
+    default:
+      LOG(ERROR) << "SDL event: " << src.type << " is not supported";
+      ORTHANC_ASSERT(false, "Not supported");
+    }
+    dest.sym[0] = src.key.keysym.sym;
+    dest.sym[1] = 0;
+
+    if (src.key.keysym.mod & KMOD_CTRL)
+      dest.ctrlKey = true;
+    else
+      dest.ctrlKey = false;
+
+    if (src.key.keysym.mod & KMOD_SHIFT)
+      dest.shiftKey = true;
+    else
+      dest.shiftKey = false;
+
+    if (src.key.keysym.mod & KMOD_ALT)
+      dest.altKey = true;
+    else
+      dest.altKey = false;
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetSdlResizeCallback(
+    std::string canvasId, void* userData, bool capture, OnSdlWindowResizeFunc func)
+  {
+    resizeHandlers_.push_back(EventHandlerData<OnSdlWindowResizeFunc>(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::SetMouseDblClickCallback(
+    std::string canvasId, void* userData, bool capture, OnMouseEventFunc func)
+  {
+    mouseDblCickHandlers_.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)
+  {
+    keyDownHandlers_.push_back(EventHandlerData<OnKeyDownFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetKeyUpCallback(
+    std::string canvasId, void* userData, bool capture, OnKeyUpFunc    func)
+  {
+    keyUpHandlers_.push_back(EventHandlerData<OnKeyUpFunc>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::SetGenericSdlEventCallback(
+    std::string canvasId, void* userData, bool capture, OnSdlEventCallback func)
+  {
+    sdlEventHandlers_.push_back(EventHandlerData<OnSdlEventCallback>(canvasId, func, userData));
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnAnimationFrame()
+  {
+    std::vector<size_t> disabledAnimationHandlers;
+    for (size_t i = 0; i < animationFrameHandlers_.size(); i++)
+    {
+      // TODO: fix time 
+      bool goOn = (*(animationFrameHandlers_[i].first))(0, animationFrameHandlers_[i].second);
+
+      // If the function returns false, we need to emulate what happens in Web 
+      // and remove the function from the handlers...
+      if (!goOn)
+        disabledAnimationHandlers.push_back(i);
+    }
+    for (size_t i = 0; i < disabledAnimationHandlers.size(); i++)
+    {
+      ORTHANC_ASSERT(animationFrameHandlers_.begin() + disabledAnimationHandlers[i] < animationFrameHandlers_.end());
+      animationFrameHandlers_.erase(animationFrameHandlers_.begin() + disabledAnimationHandlers[i]);
+    }
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnResize(unsigned int width, unsigned int height)
+  {
+    for (size_t i = 0; i < resizeHandlers_.size(); i++)
+    {
+      (*(resizeHandlers_[i].func))(
+        resizeHandlers_[i].canvasName, NULL, width, height, resizeHandlers_[i].userData);
+    }
+  }
+
+
+
+  void GuiAdapter::OnSdlGenericEvent(const SDL_Event& sdlEvent)
+  {
+    // Events related to a window are only sent to the related canvas
+    // User events are sent to everyone (we can't filter them here)
+    
+    /*
+    SDL_WindowEvent    SDL_WINDOWEVENT
+    SDL_KeyboardEvent     SDL_KEYDOWN
+                          SDL_KEYUP
+    SDL_TextEditingEvent  SDL_TEXTEDITING
+    SDL_TextInputEvent    SDL_TEXTINPUT
+    SDL_MouseMotionEvent  SDL_MOUSEMOTION
+    SDL_MouseButtonEvent  SDL_MOUSEBUTTONDOWN 
+                          SDL_MOUSEBUTTONUP
+    SDL_MouseWheelEvent   SDL_MOUSEWHEEL
+    SDL_UserEvent         SDL_USEREVENT through ::SDL_LASTEVENT-1
+    */
+
+    // if this string is left empty, it means the message will be sent to
+    // all widgets.
+    // otherwise, it contains the originating message window title
+
+    std::string windowTitle;
+    uint32_t windowId = 0;
+
+    if (sdlEvent.type == SDL_WINDOWEVENT)
+      windowId = sdlEvent.window.windowID;
+    else if (sdlEvent.type == SDL_KEYDOWN || sdlEvent.type == SDL_KEYUP)
+      windowId = sdlEvent.key.windowID;
+    else if (sdlEvent.type == SDL_TEXTEDITING)
+      windowId = sdlEvent.edit.windowID;
+    else if (sdlEvent.type == SDL_TEXTINPUT)
+      windowId = sdlEvent.text.windowID;
+    else if (sdlEvent.type == SDL_MOUSEMOTION)
+      windowId = sdlEvent.motion.windowID;
+    else if (sdlEvent.type == SDL_MOUSEBUTTONDOWN || sdlEvent.type == SDL_MOUSEBUTTONUP)
+      windowId = sdlEvent.button.windowID;
+    else if (sdlEvent.type == SDL_MOUSEWHEEL)
+      windowId = sdlEvent.wheel.windowID;
+    else if (sdlEvent.type >= SDL_USEREVENT && sdlEvent.type <= (SDL_LASTEVENT-1))
+      windowId = sdlEvent.user.windowID;
+
+    if (windowId != 0)
+    {
+      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!");
+      windowTitle = windowTitleSz;
+      ORTHANC_ASSERT(windowTitle != "", "Window ID \"" << windowId << "\" has an empty window title!");
+    }
+
+    for (size_t i = 0; i < sdlEventHandlers_.size(); i++)
+    {
+      // normally, the handlers return a bool indicating whether they
+      // have handled the event or not, but we don't really care about this
+      std::string& canvasName = sdlEventHandlers_[i].canvasName;
+      
+      bool sendEvent = true;
+
+      if (windowTitle != "" && (canvasName != windowTitle))
+        sendEvent = false;
+
+      if (sendEvent)
+      {
+        OnSdlEventCallback func = sdlEventHandlers_[i].func;
+        (*func)(canvasName, sdlEvent, sdlEventHandlers_[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;
+    }
+  }
+
+
+  void GuiAdapter::OnKeyboardEvent(uint32_t windowID, const GuiAdapterKeyboardEvent& event)
+  {
+    // only one-letter (ascii) keyboard events supported for now
+    ORTHANC_ASSERT(event.sym[0] != 0);
+    ORTHANC_ASSERT(event.sym[1] == 0);
+
+    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_KEYDOWN:
+      for (size_t i = 0; i < keyDownHandlers_.size(); i++)
+      {
+        (*(keyDownHandlers_[i].func))(windowTitle, &event, keyDownHandlers_[i].userData);
+      }
+      break;
+    case GUIADAPTER_EVENT_KEYUP:
+      for (size_t i = 0; i < keyUpHandlers_.size(); i++)
+      {
+        (*(keyUpHandlers_[i].func))(windowTitle, &event, keyUpHandlers_[i].userData);
+      }
+      break;
+    default:
+      ORTHANC_ASSERT(false, "Wrong event.type: " << event.type << " in GuiAdapter::OnKeyboardEvent(...)");
+      break;
+    }
+  }
+
+  // SDL ONLY
+  void GuiAdapter::OnMouseEvent(uint32_t windowID, const GuiAdapterMouseEvent& event)
+  {
+    if (windowID == 0)
+    {
+      LOG(WARNING) << "GuiAdapter::OnMouseEvent -- windowID == 0 and event won't be routed!";
+    }
+    else
+    {
+      // 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_MOUSEDBLCLICK:
+        for (size_t i = 0; i < mouseDblCickHandlers_.size(); i++)
+        {
+          if (mouseDblCickHandlers_[i].canvasName == windowTitle)
+            (*(mouseDblCickHandlers_[i].func))(windowTitle, &event, mouseDblCickHandlers_[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;
+      }
+    }
+  }
+
+
+  // extern void Debug_SetContextToBeKilled(std::string title);
+  // extern void Debug_SetContextToBeRestored(std::string title);
+
+  // 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
+
+#if 0
+  // TODO: remove this when generic sdl event handlers are implemented in 
+  // the DoseView
+  // SDL ONLY
+  bool GuiAdapter::IsSdlViewPortRefreshEvent(const SDL_Event& event) const
+  {
+    SDL_Window* sdlWindow = SDL_GetWindowFromID(event.window.windowID);
+
+    ORTHANC_ASSERT(sdlWindow != NULL, "Window ID \"" << event.window.windowID << "\" is not a valid SDL window ID!");
+
+    const char* windowTitleSz = SDL_GetWindowTitle(sdlWindow);
+
+    // now we need to find the DoseView from from the canvas name!
+    // (and retrieve the SdlViewport)
+    boost::shared_ptr<IGuiAdapterWidget> foundWidget;
+    VisitWidgets([&foundWidget, windowTitleSz](auto widget)
+    {
+      if (widget->GetCanvasIdentifier() == std::string(windowTitleSz))
+        foundWidget = widget;
+    });
+    ORTHANC_ASSERT(foundWidget, "The window named: \"" << windowTitleSz << "\" was not found in the registered widgets!");
+    return foundWidget->GetSdlViewport().IsRefreshEvent(event);
+  }
+#endif
+
+  // SDL ONLY
+  void GuiAdapter::Run(GuiAdapterRunFunc func, void* cookie)
+  {
+#if 1
+    // TODO: MAKE THIS DYNAMIC !!! See SdlOpenGLViewport vs Cairo in ViewportWrapper
+# if ORTHANC_ENABLE_OPENGL == 1 && !defined(__APPLE__)
+    glEnable(GL_DEBUG_OUTPUT);
+    glDebugMessageCallback(OpenGLMessageCallback, 0);
+# endif
+#endif
+
+    // Uint32 SDL_GetWindowID(SDL_Window* window)
+    // SDL_Window* SDL_GetWindowFromID(Uint32 id)   // may return NULL
+
+    bool stop = false;
+    while (!stop)
+    {
+      {
+        // TODO: lock all viewports here! (use a scoped object)
+        if(func != NULL)
+          (*func)(cookie);
+        OnAnimationFrame(); // in SDL we must call it
+      }
+
+      while (!stop)
+      {
+        std::vector<SDL_Event> sdlEvents;
+        std::map<Uint32,SDL_Event> userEventsMap;
+        
+        SDL_Event sdlEvent;
+
+        // FIRST: collect all pending events
+        while (SDL_PollEvent(&sdlEvent) != 0)
+        {
+          if ( (sdlEvent.type >= SDL_USEREVENT) && 
+               (sdlEvent.type <= SDL_USEREVENT) )
+          {
+            // we don't want to have multiple events with the same event.type
+            userEventsMap[sdlEvent.type] = sdlEvent;
+          }
+          else
+          {
+            sdlEvents.push_back(sdlEvent);
+          }
+        }
+
+        // SECOND: collect all user events
+        for (std::map<Uint32,SDL_Event>::const_iterator it = userEventsMap.begin(); it != userEventsMap.end(); ++it)
+          sdlEvents.push_back(it->second);
+                
+        // now process the events
+        for (std::vector<SDL_Event>::const_iterator it = sdlEvents.begin(); it != sdlEvents.end(); ++it)
+        {
+          const SDL_Event& sdlEvent = *it;
+          // TODO: lock all viewports here! (use a scoped object)
+
+          if (sdlEvent.type == SDL_QUIT)
+          {
+            // TODO: call exit callbacks here
+            stop = true;
+            break;
+          }
+          else if ((sdlEvent.type == SDL_MOUSEMOTION) ||
+            (sdlEvent.type == SDL_MOUSEBUTTONDOWN) ||
+                   (sdlEvent.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, sdlEvent);
+            OnMouseEvent(sdlEvent.window.windowID, dest);
+  #if 0
+            // for reference, how to create trackers
+            if (tracker)
+            {
+              PointerEvent e;
+              e.AddPosition(compositor.GetPixelCenterCoordinates(
+                sdlEvent.button.x, sdlEvent.button.y));
+              tracker->PointerMove(e);
+            }
+  #endif
+          }
+          else if (sdlEvent.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, sdlEvent);
+            OnMouseWheelEvent(sdlEvent.window.windowID, dest);
+
+            //KeyboardModifiers modifiers = GetKeyboardModifiers(keyboardState, scancodeCount);
+
+            //int x, y;
+            //SDL_GetMouseState(&x, &y);
+
+            //if (sdlEvent.wheel.y > 0)
+            //{
+            //  locker.GetCentralViewport().MouseWheel(MouseWheelDirection_Up, x, y, modifiers);
+            //}
+            //else if (sdlEvent.wheel.y < 0)
+            //{
+            //  locker.GetCentralViewport().MouseWheel(MouseWheelDirection_Down, x, y, modifiers);
+            //}
+          }
+          else if (sdlEvent.type == SDL_WINDOWEVENT &&
+            (sdlEvent.window.event == SDL_WINDOWEVENT_RESIZED ||
+             sdlEvent.window.event == SDL_WINDOWEVENT_SIZE_CHANGED))
+          {
+  #if 0
+            tracker.reset();
+  #endif
+            OnResize(sdlEvent.window.data1, sdlEvent.window.data2);
+          }
+          else if (sdlEvent.type == SDL_KEYDOWN && sdlEvent.key.repeat == 0 /* Ignore key bounce */)
+          {
+            switch (sdlEvent.key.keysym.sym)
+            {
+            case SDLK_f:
+              // window.GetWindow().ToggleMaximize(); //TODO: move to particular handler
+              break;
+
+            // This commented out code was used to debug the context
+            // loss/restoring code (2019-08-10)
+            // case SDLK_k:
+            //   {
+            //     SDL_Window* window = SDL_GetWindowFromID(sdlEvent.window.windowID);
+            //     std::string windowTitle(SDL_GetWindowTitle(window));
+            //     Debug_SetContextToBeKilled(windowTitle);
+            //   }
+            //   break;
+            // case SDLK_l:
+            //   {
+            //     SDL_Window* window = SDL_GetWindowFromID(sdlEvent.window.windowID);
+            //     std::string windowTitle(SDL_GetWindowTitle(window));
+            //     Debug_SetContextToBeRestored(windowTitle);
+            //   }
+            //   break;
+
+            case SDLK_q:
+              stop = true;
+              break;
+
+            default:
+              GuiAdapterKeyboardEvent dest;
+              ConvertFromPlatform(dest, sdlEvent);
+              OnKeyboardEvent(sdlEvent.window.windowID, dest);
+              break;
+            }
+          }
+        
+          OnSdlGenericEvent(sdlEvent);
+        }
+      }
+
+      SDL_Delay(1);
+    }
+  }
+#endif
+}
+