--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Platforms/Wasm/Defaults.cpp	Tue Jun 19 16:06:32 2018 +0200
@@ -0,0 +1,252 @@
+#include "Defaults.h"
+
+#include "WasmWebService.h"
+#include <Framework/dev.h>
+#include "Framework/Widgets/TestCairoWidget.h"
+#include <Framework/Viewport/WidgetViewport.h>
+#include <Framework/Widgets/LayerWidget.h>
+#include <algorithm>
+
+static unsigned int width_ = 0;
+static unsigned int height_ = 0;
+
+/**********************************/
+
+static std::auto_ptr<OrthancStone::BasicWasmApplication> application;
+static OrthancStone::ChangeObserver changeObserver_;
+static OrthancStone::StatusBar statusBar_;
+
+
+static std::list<std::shared_ptr<OrthancStone::WidgetViewport>> viewports_;
+
+std::shared_ptr<OrthancStone::WidgetViewport> FindViewportSharedPtr(ViewportHandle viewport) {
+  for (const auto& v : viewports_) {
+    if (v.get() == viewport) {
+      return v;
+    }
+  }
+  assert(false);
+  return std::shared_ptr<OrthancStone::WidgetViewport>();
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+  using namespace OrthancStone;
+
+  // when WASM needs a C++ viewport
+  ViewportHandle EMSCRIPTEN_KEEPALIVE CreateCppViewport() {
+    
+    std::shared_ptr<OrthancStone::WidgetViewport> viewport(new OrthancStone::WidgetViewport);
+    printf("viewport %x\n", viewport.get());
+
+    viewports_.push_back(viewport);
+
+    printf("There are now %d viewports in C++\n", viewports_.size());
+
+    viewport->SetStatusBar(statusBar_);
+    viewport->Register(changeObserver_);
+
+    return viewport.get();
+  }
+
+  // when WASM does not need a viewport anymore, it should release it 
+  void EMSCRIPTEN_KEEPALIVE ReleaseCppViewport(ViewportHandle viewport) {
+    viewports_.remove_if([viewport](const std::shared_ptr<OrthancStone::WidgetViewport>& v) { return v.get() == viewport;});
+
+    printf("There are now %d viewports in C++\n", viewports_.size());
+  }
+
+  void EMSCRIPTEN_KEEPALIVE CreateWasmApplication(ViewportHandle viewport) {
+
+    printf("CreateWasmApplication\n");
+
+    application.reset(CreateUserApplication());
+
+    boost::program_options::options_description options;
+    application->DeclareStartupOptions(options);
+  }
+
+  void EMSCRIPTEN_KEEPALIVE SetStartupParameter(const char* keyc,
+                                                  const char* value) {
+    application->SetStartupParameter(keyc, value);
+  }
+
+  void EMSCRIPTEN_KEEPALIVE StartWasmApplication() {
+
+    printf("StartWasmApplication\n");
+
+    // recreate a command line from uri arguments and parse it
+    boost::program_options::variables_map parameters;
+    application->GetStartupParameters(parameters);
+
+    BasicWasmApplicationContext& context = dynamic_cast<BasicWasmApplicationContext&>(application->CreateApplicationContext(OrthancStone::WasmWebService::GetInstance(), NULL));
+    application->Initialize(statusBar_, parameters);
+
+//    viewport->SetSize(width_, height_);
+    printf("StartWasmApplication - completed\n");
+  }
+  
+  void EMSCRIPTEN_KEEPALIVE NotifyUpdateContent()
+  {
+    for (auto viewport : viewports_) {
+      // TODO Only launch the JavaScript timer if "HasUpdateContent()"
+      if (viewport->HasUpdateContent())
+      {
+        viewport->UpdateContent();
+      }
+
+    }
+
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportSetSize(ViewportHandle viewport, unsigned int width, unsigned int height)
+  {
+    width_ = width;
+    height_ = height;
+    
+    viewport->SetSize(width, height);
+  }
+
+  int EMSCRIPTEN_KEEPALIVE ViewportRender(ViewportHandle viewport,
+                                          unsigned int width,
+                                          unsigned int height,
+                                          uint8_t* data)
+  {
+    changeObserver_.Reset();
+
+    //printf("ViewportRender called %dx%d\n", width, height);
+    if (width == 0 ||
+        height == 0)
+    {
+      return 1;
+    }
+
+    Orthanc::ImageAccessor surface;
+    surface.AssignWritable(Orthanc::PixelFormat_BGRA32, width, height, 4 * width, data);
+
+    viewport->Render(surface);
+
+    // Convert from BGRA32 memory layout (only color mode supported by
+    // Cairo, which corresponds to CAIRO_FORMAT_ARGB32) to RGBA32 (as
+    // expected by HTML5 canvas). This simply amounts to swapping the
+    // B and R channels.
+    uint8_t* p = data;
+    for (unsigned int y = 0; y < height; y++) {
+      for (unsigned int x = 0; x < width; x++) {
+        uint8_t tmp = p[0];
+        p[0] = p[2];
+        p[2] = tmp;
+        
+        p += 4;
+      }
+    }
+
+    return 1;
+  }
+
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseDown(ViewportHandle viewport,
+                                              unsigned int rawButton,
+                                              int x,
+                                              int y,
+                                              unsigned int rawModifiers)
+  {
+    OrthancStone::MouseButton button;
+    switch (rawButton)
+    {
+      case 0:
+        button = OrthancStone::MouseButton_Left;
+        break;
+
+      case 1:
+        button = OrthancStone::MouseButton_Middle;
+        break;
+
+      case 2:
+        button = OrthancStone::MouseButton_Right;
+        break;
+
+      default:
+        return;  // Unknown button
+    }
+
+    viewport->MouseDown(button, x, y, OrthancStone::KeyboardModifiers_None /* TODO */);
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseWheel(ViewportHandle viewport,
+                                               int deltaY,
+                                               int x,
+                                               int y,
+                                               int isControl)
+  {
+    if (deltaY != 0)
+    {
+      OrthancStone::MouseWheelDirection direction = (deltaY < 0 ?
+                                                     OrthancStone::MouseWheelDirection_Up :
+                                                     OrthancStone::MouseWheelDirection_Down);
+      OrthancStone::KeyboardModifiers modifiers = OrthancStone::KeyboardModifiers_None;
+
+      if (isControl != 0)
+      {
+        modifiers = OrthancStone::KeyboardModifiers_Control;
+      }
+
+      viewport->MouseWheel(direction, x, y, modifiers);
+    }
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseMove(ViewportHandle viewport,
+                                              int x,
+                                              int y)
+  {
+    viewport->MouseMove(x, y);
+  }
+  
+  void EMSCRIPTEN_KEEPALIVE ViewportKeyPressed(ViewportHandle viewport,
+                                               const char* key, 
+                                               bool isShiftPressed, 
+                                               bool isControlPressed,
+                                               bool isAltPressed)
+                                               
+  {
+    OrthancStone::KeyboardModifiers modifiers = OrthancStone::KeyboardModifiers_None;
+    if (isShiftPressed) {
+      modifiers = static_cast<OrthancStone::KeyboardModifiers>(modifiers + OrthancStone::KeyboardModifiers_Shift);
+    }
+    if (isControlPressed) {
+      modifiers = static_cast<OrthancStone::KeyboardModifiers>(modifiers + OrthancStone::KeyboardModifiers_Control);
+    }
+    if (isAltPressed) {
+      modifiers = static_cast<OrthancStone::KeyboardModifiers>(modifiers + OrthancStone::KeyboardModifiers_Alt);
+    }
+    printf("key pressed : %c\n", key[0]);
+    viewport->KeyPressed(key[0], modifiers);
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseUp(ViewportHandle viewport)
+  {
+    viewport->MouseUp();
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseEnter(ViewportHandle viewport)
+  {
+    viewport->MouseEnter();
+  }
+  
+
+  void EMSCRIPTEN_KEEPALIVE ViewportMouseLeave(ViewportHandle viewport)
+  {
+    viewport->MouseLeave();
+  }
+
+
+#ifdef __cplusplus
+}
+#endif