From dbb5c077090c7162b30ffde58a0a2547eac6c03f Mon Sep 17 00:00:00 2001
From: Maxime Gimeno <maxime.gimeno@gmail.com>
Date: Tue, 1 Dec 2015 12:42:20 +0100
Subject: [PATCH] Draw text done. WIP Blending

---
 .../demo/Polyhedron/Scene_polyhedron_item.cpp |  7 +++
 Polyhedron/demo/Polyhedron/Viewer.cpp         | 41 +++++++++++++++-
 Polyhedron/demo/Polyhedron/Viewer.h           | 49 +++++++++++++++++++
 .../include/CGAL/IO/Polyhedron_scan_OFF.h     |  1 +
 4 files changed, 97 insertions(+), 1 deletion(-)

diff --git a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
index f715f405970..45ce88dc13c 100644
--- a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
@@ -36,6 +36,9 @@
 #include <boost/foreach.hpp>
 #include <boost/container/flat_map.hpp>
 
+
+#include <QPainter>
+
 namespace PMP = CGAL::Polygon_mesh_processing;
 
 
@@ -832,6 +835,7 @@ void Scene_polyhedron_item::set_erase_next_picked_facet(bool b)
 }
 
 void Scene_polyhedron_item::draw(CGAL::Three::Viewer_interface* viewer) const {
+
     if(!are_buffers_filled)
     {
         compute_normals_and_vertices();
@@ -862,6 +866,9 @@ void Scene_polyhedron_item::draw(CGAL::Three::Viewer_interface* viewer) const {
         vaos[Facets]->release();
     else
         vaos[Gouraud_Facets]->release();
+
+    viewer->qglColor(Qt::black);
+    viewer->drawText(viewer->width()/2, viewer->height()/2, "CENTER");
 }
 
 // Points/Wireframe/Flat/Gouraud OpenGL drawing in a display list
diff --git a/Polyhedron/demo/Polyhedron/Viewer.cpp b/Polyhedron/demo/Polyhedron/Viewer.cpp
index 2e4c47ce637..dcc98330616 100644
--- a/Polyhedron/demo/Polyhedron/Viewer.cpp
+++ b/Polyhedron/demo/Polyhedron/Viewer.cpp
@@ -806,7 +806,17 @@ void Viewer::drawVisualHints()
         rendering_program.release();
         vao[0].release();
     }
-
+bool has_text = false;
+    if(has_text)
+    {
+    TextRenderer *textRenderer = new TextRenderer();
+    for(int i=0; i<3; i++)
+    {
+        float x = 30*i, y = 120, z=0;
+        textRenderer->addText(new TextItem(x,y,z,"Under Testing"));
+    }
+    textRenderer->draw(this);
+    }
 }
 
 void Viewer::resizeGL(int w, int h)
@@ -1131,3 +1141,32 @@ void Viewer::wheelEvent(QWheelEvent* e)
     else
         QGLViewer::wheelEvent(e);
 }
+
+void TextRenderer::draw(CGAL::Three::Viewer_interface *viewer)
+{
+    QPainter painter(viewer);
+    QRect rect;
+    qglviewer::Camera* camera = viewer->camera();
+    //fbo = new QOpenGLFramebufferObject(viewer->width(), viewer->height(),QOpenGLFramebufferObject::Depth);
+    //fbo->bind();
+    //viewer->glEnable(GL_DEPTH_TEST);
+    //viewer->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    Q_FOREACH(TextItem* item, textItems)
+    {
+        qglviewer::Vec src(item->position()->x(), item->position()->y(),item->position()->z());
+        rect = QRect(camera->projectedCoordinatesOf(src).x-item->width()/2,
+                     camera->projectedCoordinatesOf(src).y-item->height()/2,
+                     item->width(),
+                     item->height());
+        painter.setFont(item->font());
+        painter.drawText(rect, item->text());
+    }
+
+
+}
+
+ void TextRenderer::addText(TextItem *ti)
+ {
+     textItems.push_back(ti);
+ }
+
diff --git a/Polyhedron/demo/Polyhedron/Viewer.h b/Polyhedron/demo/Polyhedron/Viewer.h
index 53ed0360903..b5df436a1c6 100644
--- a/Polyhedron/demo/Polyhedron/Viewer.h
+++ b/Polyhedron/demo/Polyhedron/Viewer.h
@@ -11,6 +11,8 @@
 
 #include <QGLViewer/qglviewer.h>
 #include <QPoint>
+#include <QFont>
+#include <QOpenGLFramebufferObject>
 
 // forward declarations
 class QWidget;
@@ -92,6 +94,7 @@ protected:
       std::vector<float> *normals;
       std::vector<float> *colors;
   };
+
   //! The buffers used to draw the axis system
   QOpenGLBuffer buffers[3];
   //! The VAO used to draw the axis system
@@ -133,4 +136,50 @@ protected:
   double prev_radius;
 }; // end class Viewer
 
+//!This class holds the properties of each line of text to be rendered.
+class TextItem{
+public :
+    TextItem(float p_x, float p_y, float p_z, QString p_text, QFont font = QFont(), QColor p_color = Qt::black)
+        :x(p_x), y(p_y), z(p_z), m_text(p_text), m_font(font), color(p_color)
+    {
+       QFontMetrics fm(m_font);
+       _width = fm.width(m_text);
+       _height = fm.height();
+    }
+    QString text()const {return m_text;}
+    //!Returns the position of the center of the text, in world coordinates.
+    QVector3D *position(){return new QVector3D(x,y,z);}
+    float width(){return _width;}
+    float height(){return _height;}
+    QFont font(){return m_font;}
+private:
+    float x;
+    float y;
+    float z;
+    float _width;
+    float _height;
+    QString m_text;
+    QFont m_font;
+    QColor color;
+};//end class TextItem
+
+//!This class draws all the textItems.
+class TextRenderer{
+public:
+    TextRenderer()
+    {
+        textItems.resize(0);
+    }
+    /*!
+      * Projects each textItem from the world coordinates to the Screen coordinates
+      * and draws it.
+     */
+    void draw(CGAL::Three::Viewer_interface* viewer);
+    void addText(TextItem* ti);
+
+private:
+    std::vector<TextItem*> textItems;
+    QOpenGLFramebufferObject *fbo;
+
+};//end class TextRenderer
 #endif // VIEWER_H
diff --git a/Polyhedron_IO/include/CGAL/IO/Polyhedron_scan_OFF.h b/Polyhedron_IO/include/CGAL/IO/Polyhedron_scan_OFF.h
index 0d23b13f049..d862822e9ea 100644
--- a/Polyhedron_IO/include/CGAL/IO/Polyhedron_scan_OFF.h
+++ b/Polyhedron_IO/include/CGAL/IO/Polyhedron_scan_OFF.h
@@ -114,6 +114,7 @@ Polyhedron_scan_OFF<HDS>:: operator()( HDS& target) {
             scanner.scan_facet_vertex_index( index, i);
             B.add_vertex_to_facet( index);
         }
+        //TO DO : Insert read color
         B.end_facet();
         scanner.skip_to_next_facet( i);
     }