New picking finished. Far more efficient.

Polyhedron/demo/Polyhedron/Scene.cpp

@@ -331,10 +331,10 @@ Scene::drawWithNames(CGAL::Three::Viewer_interface* viewer)
 {
     draw_aux(true, viewer);
 }
-
 void 
 Scene::draw_aux(bool with_names, CGAL::Three::Viewer_interface* viewer)
 {
+    QMap<float, int> picked_item_IDs;
     if(!ms_splatting->viewer_is_set)
         ms_splatting->setViewer(viewer);
     if(!gl_init)
@@ -343,7 +343,8 @@ Scene::draw_aux(bool with_names, CGAL::Three::Viewer_interface* viewer)
     for(int index = 0; index < m_entries.size(); ++index)
     {
         if(with_names) {
-            viewer->glPushName(index);
+            glClearDepth(1.0);
+            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
         }
         CGAL::Three::Scene_item& item = *m_entries[index];
         if(item.visible())
@@ -375,16 +376,23 @@ Scene::draw_aux(bool with_names, CGAL::Three::Viewer_interface* viewer)
             }
         }
         if(with_names) {
-            viewer->glPopName();
+
+            //    read depth buffer at pick location;
+            float depth = 1.0;
+            glReadPixels(picked_pixel.x(),picked_pixel.y(),1,1,GL_DEPTH_COMPONENT, GL_FLOAT, &depth);
+            if (depth != 1.0)
+            {
+                //add object to list of picked objects;
+                picked_item_IDs[depth] = index;
             }
         }
-glDepthFunc(GL_LEQUAL);
+    }
+    if(!with_names)
+    {
+        glDepthFunc(GL_LEQUAL);
         // Wireframe OpenGL drawing
         for(int index = 0; index < m_entries.size(); ++index)
         {
-        if(with_names) {
-            viewer->glPushName(index);
-        }
             CGAL::Three::Scene_item& item = *m_entries[index];
             if(item.visible())
             {
@@ -433,18 +441,12 @@ glDepthFunc(GL_LEQUAL);
                     }
                 }
             }
-        if(with_names) {
-            viewer->glPopName();
-        }
         }
 
 
         // Points OpenGL drawing
         for(int index = 0; index < m_entries.size(); ++index)
         {
-        if(with_names) {
-            viewer->glPushName(index);
-        }
             CGAL::Three::Scene_item& item = *m_entries[index];
             if(item.visible())
             {
@@ -461,9 +463,6 @@ glDepthFunc(GL_LEQUAL);
                         item.draw_points();
                 }
             }
-        if(with_names) {
-            viewer->glPopName();
-        }
         }
         glDepthFunc(GL_LESS);
         // Splatting
@@ -501,14 +500,27 @@ glDepthFunc(GL_LEQUAL);
             ms_splatting->finalize();
 
         }
-
+    }
-    //scrolls the sceneView to the selected item's line.
+    else
-    if(picked)
+    {
-        Q_EMIT(itemPicked(index_map.key(mainSelectionIndex())));
+        QList<float> depths = picked_item_IDs.keys();
+        if(!depths.isEmpty())
+        {
+            qSort(depths);
+            int id = picked_item_IDs[depths.first()];
+            setSelectedItemIndex(id);
+            viewer->setSelectedName(id);
+        }
+    }
     if(with_names)
         picked = true;
     else
         picked = false;
+    //scrolls the sceneView to the selected item's line.
+    if(picked)
+    {
+        Q_EMIT(itemPicked(index_map.key(mainSelectionIndex())));
+    }
 
 }
 

Polyhedron/demo/Polyhedron/Scene.h

@@ -112,6 +112,8 @@ public:
   void initializeGL();
   /*! Is called by Viewer::draw(). Is deprecated and does nothing.*/
   void draw();
+  /*! Sets the screen coordinates of the currently picked point.*/
+  void setPickedPixel(const QPoint &p) {picked_pixel = p;}
   /*! Is deprecated and does nothing.*/
   void drawWithNames();
   /*! Is called by Viewer::draw(Viewer_interface*). Calls draw_aux(false, viewer).
@@ -274,6 +276,7 @@ private:
   //!Index of the item_B.
   int item_B;
   bool picked;
+  QPoint picked_pixel;
   bool gl_init;
   static GlSplat::SplatRenderer* ms_splatting;
   static int ms_splattingCounter;

Polyhedron/demo/Polyhedron/Viewer.cpp

@@ -237,6 +237,7 @@ void Viewer::mousePressEvent(QMouseEvent* event)
   if(event->button() == Qt::RightButton &&
      event->modifiers().testFlag(Qt::ShiftModifier)) 
   {
+
     select(event->pos());
     requestContextMenu(event->globalPos());
     event->accept();
@@ -435,7 +436,6 @@ void Viewer::attrib_buffers(int program_name) const {
         mv_mat.data()[i] = GLfloat(d_mat[i]);
     for (int i=0; i<16; ++i)
         pick_mat.data()[i] = this->pickMatrix_[i];
-
     mvp_mat = pick_mat * mvp_mat;
 
     const_cast<Viewer*>(this)->glGetIntegerv(GL_LIGHT_MODEL_TWO_SIDE,
@@ -546,7 +546,7 @@ void Viewer::attrib_buffers(int program_name) const {
 
 
 void Viewer::pickMatrix(GLdouble x, GLdouble y, GLdouble width, GLdouble height,
-GLint viewport[4])
+GLint viewport[4]) const
 {
  //GLfloat m[16];
  GLfloat sx, sy;
@@ -575,21 +575,25 @@ GLint viewport[4])
   M(3, 2) = 0.0;
   M(3, 3) = 1.0;
  #undef M
-
- //pickMatrix_[i] = m[i];
 }
 void Viewer::beginSelection(const QPoint &point)
 {
-    QGLViewer::beginSelection(point);
+   // QGLViewer::beginSelection(point);
+    makeCurrent();
     //set the picking matrix to allow the picking
     static GLint viewport[4];
     camera()->getViewport(viewport);
-    pickMatrix(point.x(), point.y(), selectRegionWidth(), selectRegionHeight(), viewport);
+    pickMatrix(point.x(), point.y(), 1, 1, viewport);
+    glEnable(GL_SCISSOR_TEST);
+    glScissor(point.x(), point.y(), 1, 1);
+    d->scene->setPickedPixel(point);
 
 }
-void Viewer::endSelection(const QPoint& point)
+void Viewer::endSelection(const QPoint&)
 {
-  QGLViewer::endSelection(point);
+    //QGLViewer::endSelection(point);
+    glDisable(GL_SCISSOR_TEST);
+
    //set the pick matrix to Identity
     for(int i=0; i<16; i++)
         pickMatrix_[i]=0;

Polyhedron/demo/Polyhedron/Viewer.h

@@ -114,7 +114,7 @@ protected:
   * the drawing system changed to use shaders, and these need this value. pickMatrix_ is passed to the shaders in
   * Scene_item::attrib_buffers(CGAL::Three::Viewer_interface* viewer, int program_name).*/
   void pickMatrix(GLdouble x, GLdouble y, GLdouble width, GLdouble height,
-                  GLint viewport[4]);
+                  GLint viewport[4]) const;
   /*!
    * \brief makeArrow creates an arrow and stores it in a struct of vectors.
    * \param R the radius of the arrow.

Three/include/CGAL/Three/Scene_draw_interface.h

@@ -22,6 +22,7 @@
 #define SCENE_DRAW_INTERFACE_H
 
 class QKeyEvent;
+class QPoint;
 namespace CGAL
 {
 namespace Three {
@@ -36,6 +37,8 @@ public:
   virtual void draw() = 0;
   virtual void draw(CGAL::Three::Viewer_interface*) { draw(); };
   virtual void drawWithNames() = 0;
+ /*! Sets the screen coordinates of the currently picked point.*/
+  virtual void setPickedPixel(const QPoint &e) = 0;
   virtual void drawWithNames(CGAL::Three::Viewer_interface*) { drawWithNames(); }
   virtual bool keyPressEvent(QKeyEvent* e) = 0;
   virtual float get_bbox_length() const = 0;

Three/include/CGAL/Three/Viewer_interface.h

@@ -109,7 +109,7 @@ public:
   //! Used by the items to avoid SEGFAULT.
   bool extension_is_found;
   //!The matrix used for the picking.
-  GLfloat pickMatrix_[16];
+  mutable GLfloat pickMatrix_[16];
   //!Sets the binding for SHIFT+LEFT CLICK to SELECT (initially used in Scene_polyhedron_selection_item.h)
   void setBindingSelect()
   {