refactor: moved country picking to a separate class

Arrangement_on_surface_2/demo/earth/CMakeLists.txt

@@ -88,11 +88,12 @@ source_group( "Graphics_Geometry"  FILES ${source_files_graphics_geometry} )
 
 # GUI
 file(GLOB source_files_gui
-  Camera_manip.h            Camera_manip.cpp
-  Camera_manip_rot.h        Camera_manip_rot.cpp
-  Camera_manip_rot_bpa.h    Camera_manip_rot_bpa.cpp
-  Camera_manip_zoom.h       Camera_manip_zoom.cpp
-  GUI_event_handler.h       GUI_event_handler.cpp 
+  Camera_manip.h              Camera_manip.cpp
+  Camera_manip_rot.h          Camera_manip_rot.cpp
+  Camera_manip_rot_bpa.h      Camera_manip_rot_bpa.cpp
+  Camera_manip_zoom.h         Camera_manip_zoom.cpp
+  GUI_country_pick_handler.h  GUI_country_pick_handler.cpp
+  GUI_event_handler.h         GUI_event_handler.cpp 
 )
 source_group( "GUI"  FILES ${source_files_gui} )
 

Arrangement_on_surface_2/demo/earth/GUI_country_pick_handler.cpp

@@ -0,0 +1,117 @@
+// Copyright(c) 2012, 2020  Tel - Aviv University(Israel).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org).
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
+//
+// Author(s): Engin Deniz Diktas <[email protected]>
+
+#include "GUI_country_pick_handler.h"
+
+//#include <qvector3d.h>
+
+
+GUI_country_pick_handler::GUI_country_pick_handler(Main_widget& main_widget) :
+  m_main_widget(main_widget),
+  m_camera(main_widget.get_camera())
+{
+
+}
+
+void GUI_country_pick_handler::mouse_press_event(QMouseEvent* e)
+{
+  // handle country selection
+  if (e->button() == Qt::RightButton)
+  {
+    auto p = e->pos();
+    QVector3D  sp0(p.x(), m_vp_height - p.y(), 0);
+    QVector3D  sp1(p.x(), m_vp_height - p.y(), 1);
+
+    auto proj = m_camera.get_projection_matrix();
+    auto view = m_camera.get_view_matrix();
+    auto model_view = view * m_main_widget.get_model_matrix();
+    QRect viewport(0, 0, m_vp_width, m_vp_height);
+    auto wp0 = sp0.unproject(model_view, proj, viewport);
+    auto wp1 = sp1.unproject(model_view, proj, viewport);
+
+    // ASSERTION!!!
+    m_main_widget.set_mouse_pos(wp0);
+
+    // define a ray from the camera pos to the world-point
+    //auto o = m_camera.get_pos();
+    //auto u = wp - o;
+    auto o = wp0;
+    auto u = wp1 - wp0;
+
+    // solve the quadratic equation to check for intersection of ray with sphere
+    auto a = QVector3D::dotProduct(u, u);
+    auto b = 2 * QVector3D::dotProduct(u, o);
+    auto c = QVector3D::dotProduct(o, o) - 1;
+    auto d = b * b - 4 * a * c;
+
+    float ti = -1;
+    if (abs(d) < std::numeric_limits<float>::epsilon())
+    {
+      // single intersection
+      ti = -b / (2 * a);
+    }
+    else
+    {
+      if (d < 0)
+      {
+        // no intersection
+        return;
+      }
+      else
+      {
+        // two intersections
+        auto sd = sqrt(d);
+        auto t1 = (-b - sd) / (2 * a);
+        auto t2 = (-b + sd) / (2 * a);
+        if (t1 > 0 && t2 > 0)
+          ti = std::min(t1, t2);
+        else if (t1 > 0)
+          ti = t1;
+        else
+          ti = t2;
+      }
+    }
+
+    //m_mouse_pos = o + ti * u;
+    auto pos = o + ti * u;
+    m_main_widget.set_mouse_pos(pos);
+    static std::string prev_picked_country;
+    auto& arrh = m_main_widget.get_arr_handle();
+    auto picked_country = Aos::locate_country(arrh, pos);
+
+    m_main_widget.hightlight_country(picked_country);
+    //  if (!prev_picked_country.empty())
+  //  {
+  //    // dim the previous country color
+  //    auto& prev_country = m_country_triangles[prev_picked_country];
+  //    auto color = prev_country->get_color();
+  //    color *= s_dimming_factor;
+  //    color.setW(1);
+  //    prev_country->set_color(color);
+  //  }
+
+  //  if (!picked_country.empty())
+  //  {
+  //    // highlight the current country color
+  //    auto& curr_country = m_country_triangles[picked_country];
+  //    auto color = curr_country->get_color();
+  //    color /= s_dimming_factor;
+  //    color.setW(1);
+  //    curr_country->set_color(color);
+  //    qDebug() << "SELECTED COUNTRY: " << picked_country;
+  //  }
+
+  //  prev_picked_country = picked_country;
+  }
+}
+void GUI_country_pick_handler::resize(int w, int h)
+{
+  m_vp_width = w;
+  m_vp_height = h;
+}

Arrangement_on_surface_2/demo/earth/GUI_country_pick_handler.h

@@ -0,0 +1,35 @@
+// Copyright(c) 2012, 2020  Tel - Aviv University(Israel).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org).
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
+//
+// Author(s): Engin Deniz Diktas <[email protected]>
+
+#ifndef GUI_COUNTRY_PICK_HANDLER_H
+#define GUI_COUNTRY_PICK_HANDLER_H
+
+#include <qevent.h>
+#include <qvector2d.h>
+
+#include "GUI_event_handler.h"
+#include "Main_widget.h"
+
+
+class GUI_country_pick_handler : public GUI_event_handler
+{
+public:
+  GUI_country_pick_handler(Main_widget& main_widget);
+
+protected:
+  virtual void mouse_press_event(QMouseEvent* e) override;
+  virtual void resize(int w, int h) override;
+
+  Main_widget&  m_main_widget;
+  Camera&       m_camera;
+  int           m_vp_width, m_vp_height;
+};
+
+
+#endif