--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Widgets/SliceViewerWidget.cpp	Fri Nov 09 17:26:39 2018 +0100
@@ -0,0 +1,651 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2018 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 "SliceViewerWidget.h"
+
+#include "../Layers/SliceOutlineRenderer.h"
+#include "../Toolbox/GeometryToolbox.h"
+#include "Framework/Layers/FrameRenderer.h"
+
+#include <Core/Logging.h>
+
+#include <boost/math/constants/constants.hpp>
+
+
+static const double THIN_SLICE_THICKNESS = 100.0 * std::numeric_limits<double>::epsilon();
+
+namespace OrthancStone
+{
+  class SliceViewerWidget::Scene : public boost::noncopyable
+  {
+  private:
+    CoordinateSystem3D            slice_;
+    double                        thickness_;
+    size_t                        countMissing_;
+    std::vector<ILayerRenderer*>  renderers_;
+
+  public:
+    void DeleteLayer(size_t index)
+    {
+      if (index >= renderers_.size())
+      {
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+      }
+
+      assert(countMissing_ <= renderers_.size());
+
+      if (renderers_[index] != NULL)
+      {
+        assert(countMissing_ < renderers_.size());
+        delete renderers_[index];
+        renderers_[index] = NULL;
+        countMissing_++;
+      }
+    }
+
+    Scene(const CoordinateSystem3D& slice,
+          double thickness,
+          size_t countLayers) :
+      slice_(slice),
+      thickness_(thickness),
+      countMissing_(countLayers),
+      renderers_(countLayers, NULL)
+    {
+      if (thickness <= 0)
+      {
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+      }
+    }
+
+    ~Scene()
+    {
+      for (size_t i = 0; i < renderers_.size(); i++)
+      {
+        DeleteLayer(i);
+      }
+    }
+
+    void SetLayer(size_t index,
+                  ILayerRenderer* renderer)  // Takes ownership
+    {
+      if (renderer == NULL)
+      {
+        throw Orthanc::OrthancException(Orthanc::ErrorCode_NullPointer);
+      }
+
+      DeleteLayer(index);
+
+      renderers_[index] = renderer;
+      countMissing_--;
+    }
+
+    const CoordinateSystem3D& GetSlice() const
+    {
+      return slice_;
+    }
+
+    bool HasRenderer(size_t index)
+    {
+      return renderers_[index] != NULL;
+    }
+
+    bool IsComplete() const
+    {
+      return countMissing_ == 0;
+    }
+
+    unsigned int GetCountMissing() const
+    {
+      return countMissing_;
+    }
+
+    bool RenderScene(CairoContext& context,
+                     const ViewportGeometry& view,
+                     const CoordinateSystem3D& viewportSlice)
+    {
+      bool fullQuality = true;
+      cairo_t *cr = context.GetObject();
+
+      for (size_t i = 0; i < renderers_.size(); i++)
+      {
+        if (renderers_[i] != NULL)
+        {
+          const CoordinateSystem3D& frameSlice = renderers_[i]->GetLayerSlice();
+          
+          double x0, y0, x1, y1, x2, y2;
+          viewportSlice.ProjectPoint(x0, y0, frameSlice.GetOrigin());
+          viewportSlice.ProjectPoint(x1, y1, frameSlice.GetOrigin() + frameSlice.GetAxisX());
+          viewportSlice.ProjectPoint(x2, y2, frameSlice.GetOrigin() + frameSlice.GetAxisY());
+
+          /**
+           * Now we solve the system of linear equations Ax + b = x', given:
+           *   A [0 ; 0] + b = [x0 ; y0]
+           *   A [1 ; 0] + b = [x1 ; y1]
+           *   A [0 ; 1] + b = [x2 ; y2]
+           * <=>
+           *   b = [x0 ; y0]
+           *   A [1 ; 0] = [x1 ; y1] - b = [x1 - x0 ; y1 - y0]
+           *   A [0 ; 1] = [x2 ; y2] - b = [x2 - x0 ; y2 - y0]
+           * <=>
+           *   b = [x0 ; y0]
+           *   [a11 ; a21] = [x1 - x0 ; y1 - y0]
+           *   [a12 ; a22] = [x2 - x0 ; y2 - y0]
+           **/
+
+          cairo_matrix_t transform;
+          cairo_matrix_init(&transform, x1 - x0, y1 - y0, x2 - x0, y2 - y0, x0, y0);
+
+          cairo_save(cr);
+          cairo_transform(cr, &transform);
+          
+          if (!renderers_[i]->RenderLayer(context, view))
+          {
+            cairo_restore(cr);
+            return false;
+          }
+
+          cairo_restore(cr);
+        }
+
+        if (renderers_[i] != NULL &&
+            !renderers_[i]->IsFullQuality())
+        {
+          fullQuality = false;
+        }
+      }
+
+      if (!fullQuality)
+      {
+        double x, y;
+        view.MapDisplayToScene(x, y, static_cast<double>(view.GetDisplayWidth()) / 2.0, 10);
+
+        cairo_translate(cr, x, y);
+
+#if 1
+        double s = 5.0 / view.GetZoom();
+        cairo_rectangle(cr, -s, -s, 2.0 * s, 2.0 * s);
+#else
+        // TODO Drawing filled circles makes WebAssembly crash!
+        cairo_arc(cr, 0, 0, 5.0 / view.GetZoom(), 0, 2.0 * boost::math::constants::pi<double>());
+#endif
+        
+        cairo_set_line_width(cr, 2.0 / view.GetZoom());
+        cairo_set_source_rgb(cr, 1, 1, 1);
+        cairo_stroke_preserve(cr);
+        cairo_set_source_rgb(cr, 1, 0, 0);
+        cairo_fill(cr);
+      }
+
+      return true;
+    }
+
+    void SetLayerStyle(size_t index,
+                       const RenderStyle& style)
+    {
+      if (renderers_[index] != NULL)
+      {
+        renderers_[index]->SetLayerStyle(style);
+      }
+    }
+
+    bool ContainsPlane(const CoordinateSystem3D& slice) const
+    {
+      bool isOpposite;
+      if (!GeometryToolbox::IsParallelOrOpposite(isOpposite,
+                                                 slice.GetNormal(),
+                                                 slice_.GetNormal()))
+      {
+        return false;
+      }
+      else
+      {
+        double z = (slice_.ProjectAlongNormal(slice.GetOrigin()) -
+                    slice_.ProjectAlongNormal(slice_.GetOrigin()));
+
+        if (z < 0)
+        {
+          z = -z;
+        }
+
+        return z <= thickness_;
+      }
+    }
+
+    double GetThickness() const
+    {
+      return thickness_;
+    }
+  };
+
+  
+  bool SliceViewerWidget::LookupLayer(size_t& index /* out */,
+                                      const ILayerSource& layer) const
+  {
+    LayersIndex::const_iterator found = layersIndex_.find(&layer);
+
+    if (found == layersIndex_.end())
+    {
+      return false;
+    }
+    else
+    {
+      index = found->second;
+      assert(index < layers_.size() &&
+             layers_[index] == &layer);
+      return true;
+    }
+  }
+
+
+  void SliceViewerWidget::GetLayerExtent(Extent2D& extent,
+                                         ILayerSource& source) const
+  {
+    extent.Reset();
+
+    std::vector<Vector> points;
+    if (source.GetExtent(points, slice_))
+    {
+      for (size_t i = 0; i < points.size(); i++)
+      {
+        double x, y;
+        slice_.ProjectPoint(x, y, points[i]);
+        extent.AddPoint(x, y);
+      }
+    }
+  }
+
+
+  Extent2D SliceViewerWidget::GetSceneExtent()
+  {
+    Extent2D sceneExtent;
+
+    for (size_t i = 0; i < layers_.size(); i++)
+    {
+      assert(layers_[i] != NULL);
+      Extent2D layerExtent;
+      GetLayerExtent(layerExtent, *layers_[i]);
+
+      sceneExtent.Union(layerExtent);
+    }
+
+    return sceneExtent;
+  }
+
+  
+  bool SliceViewerWidget::RenderScene(CairoContext& context,
+                                      const ViewportGeometry& view)
+  {
+    if (currentScene_.get() != NULL)
+    {
+      return currentScene_->RenderScene(context, view, slice_);
+    }
+    else
+    {
+      return true;
+    }
+  }
+
+  
+  void SliceViewerWidget::ResetPendingScene()
+  {
+    double thickness;
+    if (pendingScene_.get() == NULL)
+    {
+      thickness = 1.0;
+    }
+    else
+    {
+      thickness = pendingScene_->GetThickness();
+    }
+    
+    pendingScene_.reset(new Scene(slice_, thickness, layers_.size()));
+  }
+  
+
+  void SliceViewerWidget::UpdateLayer(size_t index,
+                                      ILayerRenderer* renderer,
+                                      const CoordinateSystem3D& slice)
+  {
+    LOG(INFO) << "Updating layer " << index;
+    
+    std::auto_ptr<ILayerRenderer> tmp(renderer);
+
+    if (renderer == NULL)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_NullPointer);
+    }
+
+    if (index >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    assert(layers_.size() == styles_.size());
+    renderer->SetLayerStyle(styles_[index]);
+
+    if (currentScene_.get() != NULL &&
+        currentScene_->ContainsPlane(slice))
+    {
+      currentScene_->SetLayer(index, tmp.release());
+      NotifyContentChanged();
+    }
+    else if (pendingScene_.get() != NULL &&
+             pendingScene_->ContainsPlane(slice))
+    {
+      pendingScene_->SetLayer(index, tmp.release());
+
+      if (currentScene_.get() == NULL ||
+          !currentScene_->IsComplete() ||
+          pendingScene_->IsComplete())
+      {
+        currentScene_ = pendingScene_;
+        NotifyContentChanged();
+      }
+    }
+  }
+
+  
+  SliceViewerWidget::SliceViewerWidget(MessageBroker& broker, 
+                                       const std::string& name) :
+    WorldSceneWidget(name),
+    IObserver(broker),
+    IObservable(broker),
+    started_(false)
+  {
+    SetBackgroundCleared(true);
+  }
+  
+  
+  SliceViewerWidget::~SliceViewerWidget()
+  {
+    for (size_t i = 0; i < layers_.size(); i++)
+    {
+      delete layers_[i];
+    }
+  }
+  
+  void SliceViewerWidget::ObserveLayer(ILayerSource& layer)
+  {
+    layer.RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::GeometryReadyMessage>
+                                   (*this, &SliceViewerWidget::OnGeometryReady));
+    // currently ignore errors layer->RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::GeometryErrorMessage>(*this, &SliceViewerWidget::...));
+    layer.RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::SliceChangedMessage>
+                                   (*this, &SliceViewerWidget::OnSliceChanged));
+    layer.RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::ContentChangedMessage>
+                                   (*this, &SliceViewerWidget::OnContentChanged));
+    layer.RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::LayerReadyMessage>
+                                   (*this, &SliceViewerWidget::OnLayerReady));
+    layer.RegisterObserverCallback(new Callable<SliceViewerWidget, ILayerSource::LayerErrorMessage>
+                                   (*this, &SliceViewerWidget::OnLayerError));
+  }
+
+
+  size_t SliceViewerWidget::AddLayer(ILayerSource* layer)  // Takes ownership
+  {
+    if (layer == NULL)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_NullPointer);
+    }
+
+    size_t index = layers_.size();
+    layers_.push_back(layer);
+    styles_.push_back(RenderStyle());
+    layersIndex_[layer] = index;
+
+    ResetPendingScene();
+
+    ObserveLayer(*layer);
+
+    ResetChangedLayers();
+
+    return index;
+  }
+
+
+  void SliceViewerWidget::ReplaceLayer(size_t index, ILayerSource* layer)  // Takes ownership
+  {
+    if (layer == NULL)
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_NullPointer);
+    }
+
+    if (index >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    delete layers_[index];
+    layers_[index] = layer;
+    layersIndex_[layer] = index;
+
+    ResetPendingScene();
+
+    ObserveLayer(*layer);
+
+    InvalidateLayer(index);
+  }
+
+
+  void SliceViewerWidget::RemoveLayer(size_t index)
+  {
+    if (index >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    ILayerSource* previousLayer = layers_[index];
+    layersIndex_.erase(layersIndex_.find(previousLayer));
+    layers_.erase(layers_.begin() + index);
+    changedLayers_.erase(changedLayers_.begin() + index);
+    styles_.erase(styles_.begin() + index);
+
+    delete layers_[index];
+
+    currentScene_->DeleteLayer(index);
+    ResetPendingScene();
+
+    NotifyContentChanged();
+  }
+
+
+  const RenderStyle& SliceViewerWidget::GetLayerStyle(size_t layer) const
+  {
+    if (layer >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    assert(layers_.size() == styles_.size());
+    return styles_[layer];
+  }
+  
+
+  void SliceViewerWidget::SetLayerStyle(size_t layer,
+                                        const RenderStyle& style)
+  {
+    if (layer >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    assert(layers_.size() == styles_.size());
+    styles_[layer] = style;
+
+    if (currentScene_.get() != NULL)
+    {
+      currentScene_->SetLayerStyle(layer, style);
+    }
+
+    if (pendingScene_.get() != NULL)
+    {
+      pendingScene_->SetLayerStyle(layer, style);
+    }
+
+    NotifyContentChanged();
+  }
+  
+
+  void SliceViewerWidget::SetSlice(const CoordinateSystem3D& slice)
+  {
+    LOG(INFO) << "Setting slice origin: (" << slice.GetOrigin()[0]
+              << "," << slice.GetOrigin()[1]
+              << "," << slice.GetOrigin()[2] << ")";
+    
+    Slice displayedSlice(slice_, THIN_SLICE_THICKNESS);
+
+    //if (!displayedSlice.ContainsPlane(slice))
+    {
+      if (currentScene_.get() == NULL ||
+          (pendingScene_.get() != NULL &&
+           pendingScene_->IsComplete()))
+      {
+        currentScene_ = pendingScene_;
+      }
+
+      slice_ = slice;
+      ResetPendingScene();
+
+      InvalidateAllLayers();   // TODO Removing this line avoid loading twice the image in WASM
+    }
+  }
+
+
+  void SliceViewerWidget::OnGeometryReady(const ILayerSource::GeometryReadyMessage& message)
+  {
+    size_t i;
+    if (LookupLayer(i, message.GetOrigin()))
+    {
+      LOG(INFO) << ": Geometry ready for layer " << i << " in " << GetName();
+
+      changedLayers_[i] = true;
+      //layers_[i]->ScheduleLayerCreation(slice_);
+    }
+    EmitMessage(GeometryChangedMessage(*this));
+  }
+  
+
+  void SliceViewerWidget::InvalidateAllLayers()
+  {
+    for (size_t i = 0; i < layers_.size(); i++)
+    {
+      assert(layers_[i] != NULL);
+      changedLayers_[i] = true;
+      
+      //layers_[i]->ScheduleLayerCreation(slice_);
+    }
+  }
+
+
+  void SliceViewerWidget::InvalidateLayer(size_t layer)
+  {
+    if (layer >= layers_.size())
+    {
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_ParameterOutOfRange);
+    }
+
+    assert(layers_[layer] != NULL);
+    changedLayers_[layer] = true;
+
+    //layers_[layer]->ScheduleLayerCreation(slice_);
+  }
+
+
+  void SliceViewerWidget::OnContentChanged(const ILayerSource::ContentChangedMessage& message)
+  {
+    size_t index;
+    if (LookupLayer(index, message.GetOrigin()))
+    {
+      InvalidateLayer(index);
+    }
+    
+    EmitMessage(SliceViewerWidget::ContentChangedMessage(*this));
+  }
+  
+
+  void SliceViewerWidget::OnSliceChanged(const ILayerSource::SliceChangedMessage& message)
+  {
+    if (message.GetSlice().ContainsPlane(slice_))
+    {
+      size_t index;
+      if (LookupLayer(index, message.GetOrigin()))
+      {
+        InvalidateLayer(index);
+      }
+    }
+    
+    EmitMessage(SliceViewerWidget::ContentChangedMessage(*this));
+  }
+  
+  
+  void SliceViewerWidget::OnLayerReady(const ILayerSource::LayerReadyMessage& message)
+  {
+    size_t index;
+    if (LookupLayer(index, message.GetOrigin()))
+    {
+      LOG(INFO) << "Renderer ready for layer " << index;
+      UpdateLayer(index, message.CreateRenderer(), message.GetSlice());
+    }
+    
+    EmitMessage(SliceViewerWidget::ContentChangedMessage(*this));
+  }
+
+
+  void SliceViewerWidget::OnLayerError(const ILayerSource::LayerErrorMessage& message)
+  {
+    size_t index;
+    if (LookupLayer(index, message.GetOrigin()))
+    {
+      LOG(ERROR) << "Using error renderer on layer " << index;
+
+      // TODO
+      //UpdateLayer(index, new SliceOutlineRenderer(slice), slice);
+
+      EmitMessage(SliceViewerWidget::ContentChangedMessage(*this));
+    }
+  }
+
+
+  void SliceViewerWidget::ResetChangedLayers()
+  {
+    changedLayers_.resize(layers_.size());
+
+    for (size_t i = 0; i < changedLayers_.size(); i++)
+    {
+      changedLayers_[i] = false;
+    }
+  }
+
+
+  void SliceViewerWidget::DoAnimation()
+  {
+    assert(changedLayers_.size() <= layers_.size());
+    
+    for (size_t i = 0; i < changedLayers_.size(); i++)
+    {
+      if (changedLayers_[i])
+      {
+        layers_[i]->ScheduleLayerCreation(slice_);
+      }
+    }
+    
+    ResetChangedLayers();
+  }
+}