diff --git a/.travis.yml b/.travis.yml
index 87ec308c40f..ceb69a47f8b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,93 +1,93 @@
-language: cpp
-dist: trusty
-sudo: required
-env:
- matrix:
-  - PACKAGE='CHECK'
-  - PACKAGE='AABB_tree Advancing_front_surface_reconstruction Algebraic_foundations '
-  - PACKAGE='Algebraic_kernel_d Algebraic_kernel_for_circles Algebraic_kernel_for_spheres '
-  - PACKAGE='Alpha_shapes_2 Alpha_shapes_3 Apollonius_graph_2 '
-  - PACKAGE='Arithmetic_kernel Arrangement_on_surface_2 Barycentric_coordinates_2 '
-  - PACKAGE='BGL Boolean_set_operations_2 Bounding_volumes '
-  - PACKAGE='Box_intersection_d CGAL_ImageIO CGAL_ipelets '
-  - PACKAGE='Circular_kernel_2 Circular_kernel_3 Circulator '
-  - PACKAGE='Combinatorial_map Cone_spanners_2 Convex_decomposition_3 '
-  - PACKAGE='Convex_hull_2 Convex_hull_3 Convex_hull_d '
-  - PACKAGE='Distance_2 Distance_3 Envelope_2 '
-  - PACKAGE='Envelope_3 Filtered_kernel Generalized_map '
-  - PACKAGE='Generator Geomview GraphicsView '
-  - PACKAGE='HalfedgeDS Hash_map Inscribed_areas '
-  - PACKAGE='Installation Interpolation Intersections_2 '
-  - PACKAGE='Intersections_3 Interval_skip_list Interval_support '
-  - PACKAGE='Inventor Jet_fitting_3 Kernel_23 '
-  - PACKAGE='Kernel_d Kinetic_data_structures Kinetic_framework '
-  - PACKAGE='Linear_cell_complex Matrix_search Mesh_2 '
-  - PACKAGE='Mesh_3 Minkowski_sum_2 Minkowski_sum_3 '
-  - PACKAGE='Modifier Modular_arithmetic Nef_2 '
-  - PACKAGE='Nef_3 Nef_S2 NewKernel_d '
-  - PACKAGE='Number_types Optimal_transportation_reconstruction_2 Partition_2 '
-  - PACKAGE='Periodic_2_triangulation_2 Periodic_3_triangulation_3 Point_set_2 '
-  - PACKAGE='Point_set_3 Point_set_processing_3 Point_set_shape_detection_3 '
-  - PACKAGE='Poisson_surface_reconstruction_3 Polygon Polygon_mesh_processing '
-  - PACKAGE='Polyhedron Polyhedron_IO Polyline_simplification_2 '
-  - PACKAGE='Polynomial Polytope_distance_d Principal_component_analysis '
-  - PACKAGE='Profiling_tools QP_solver Random_numbers '
-  - PACKAGE='Ridges_3 Scale_space_reconstruction_3 Segment_Delaunay_graph_2 '
-  - PACKAGE='Segment_Delaunay_graph_Linf_2 Skin_surface_3 Snap_rounding_2 '
-  - PACKAGE='Solver_interface Spatial_searching Spatial_sorting '
-  - PACKAGE='STL_Extension Straight_skeleton_2 Stream_lines_2 '
-  - PACKAGE='Stream_support Subdivision_method_3 Surface_mesh '
-  - PACKAGE='Surface_mesh_deformation Surface_mesher Surface_mesh_parameterization '
-  - PACKAGE='Surface_mesh_segmentation Surface_mesh_shortest_path Surface_mesh_simplification '
-  - PACKAGE='Surface_mesh_skeletonization Surface_sweep_2 TDS_2 '
-  - PACKAGE='TDS_3 Three Triangulation '
-  - PACKAGE='Triangulation_2 Triangulation_3 Union_find '
-  - PACKAGE='Visibility_2 Voronoi_diagram_2 '
-  - PACKAGE='Polyhedron_demo'
-install:
-before_script:
-- mkdir -p build
-- cd build
-- cmake -DCGAL_HEADER_ONLY=ON -DWITH_demos:BOOL=TRUE -DWITH_examples:BOOL=true -DWITH_tests:BOOL=TRUE -DCMAKE_CXX_FLAGS_RELEASE=-DCGAL_NDEBUG ..
-- make
-- cd ..
-script:
+language: cpp 
+dist: trusty 
+sudo: required 
+env: 
+ matrix: 
+  - PACKAGE='CHECK' 
+  - PACKAGE='AABB_tree Advancing_front_surface_reconstruction Algebraic_foundations ' 
+  - PACKAGE='Algebraic_kernel_d Algebraic_kernel_for_circles Algebraic_kernel_for_spheres ' 
+  - PACKAGE='Alpha_shapes_2 Alpha_shapes_3 Apollonius_graph_2 ' 
+  - PACKAGE='Arithmetic_kernel Arrangement_on_surface_2 Barycentric_coordinates_2 ' 
+  - PACKAGE='BGL Boolean_set_operations_2 Bounding_volumes ' 
+  - PACKAGE='Box_intersection_d CGAL_ImageIO CGAL_ipelets ' 
+  - PACKAGE='Circular_kernel_2 Circular_kernel_3 Circulator ' 
+  - PACKAGE='Combinatorial_map Cone_spanners_2 Convex_decomposition_3 ' 
+  - PACKAGE='Convex_hull_2 Convex_hull_3 Convex_hull_d ' 
+  - PACKAGE='Distance_2 Distance_3 Envelope_2 ' 
+  - PACKAGE='Envelope_3 Filtered_kernel Generalized_map ' 
+  - PACKAGE='Generator Geomview GraphicsView ' 
+  - PACKAGE='HalfedgeDS Hash_map Inscribed_areas ' 
+  - PACKAGE='Installation Interpolation Intersections_2 ' 
+  - PACKAGE='Intersections_3 Interval_skip_list Interval_support ' 
+  - PACKAGE='Inventor Jet_fitting_3 Kernel_23 ' 
+  - PACKAGE='Kernel_d Kinetic_data_structures Kinetic_framework ' 
+  - PACKAGE='Linear_cell_complex Matrix_search Mesh_2 ' 
+  - PACKAGE='Mesh_3 Minkowski_sum_2 Minkowski_sum_3 ' 
+  - PACKAGE='Modifier Modular_arithmetic Nef_2 ' 
+  - PACKAGE='Nef_3 Nef_S2 NewKernel_d ' 
+  - PACKAGE='Number_types Optimal_transportation_reconstruction_2 Partition_2 ' 
+  - PACKAGE='Periodic_2_triangulation_2 Periodic_3_triangulation_3 Point_set_2 ' 
+  - PACKAGE='Point_set_3 Point_set_processing_3 Point_set_shape_detection_3 ' 
+  - PACKAGE='Poisson_surface_reconstruction_3 Polygon Polygon_mesh_processing ' 
+  - PACKAGE='Polyhedron Polyhedron_IO Polyline_simplification_2 ' 
+  - PACKAGE='Polynomial Polytope_distance_d Principal_component_analysis ' 
+  - PACKAGE='Profiling_tools QP_solver Random_numbers ' 
+  - PACKAGE='Ridges_3 Scale_space_reconstruction_3 Segment_Delaunay_graph_2 ' 
+  - PACKAGE='Segment_Delaunay_graph_Linf_2 Skin_surface_3 Snap_rounding_2 ' 
+  - PACKAGE='Solver_interface Spatial_searching Spatial_sorting ' 
+  - PACKAGE='STL_Extension Straight_skeleton_2 Stream_lines_2 ' 
+  - PACKAGE='Stream_support Subdivision_method_3 Surface_mesh ' 
+  - PACKAGE='Surface_mesh_deformation Surface_mesher Surface_mesh_parameterization ' 
+  - PACKAGE='Surface_mesh_segmentation Surface_mesh_shortest_path Surface_mesh_simplification ' 
+  - PACKAGE='Surface_mesh_skeletonization Surface_sweep_2 TDS_2 ' 
+  - PACKAGE='TDS_3 Three Triangulation ' 
+  - PACKAGE='Triangulation_2 Triangulation_3 Union_find ' 
+  - PACKAGE='Visibility_2 Voronoi_diagram_2 ' 
+  - PACKAGE='Polyhedron_demo' 
+compiler: 
+  - clang-3.6
+  - gcc  
+install: 
+  - if [[ "$CXX" = "clang++" ]]; then export CXX=clang++-3.6 CC=clang-3.6; fi
+before_script: 
+- mkdir -p build 
+- cd build 
+- cmake -DCGAL_HEADER_ONLY=ON -DQt5_DIR="/opt/qt55/lib/cmake/Qt5" -DQt5Svg_DIR="/opt/qt55/lib/cmake/Qt5Svg" -DQt5OpenGL_DIR="/opt/qt55/lib/cmake/Qt5OpenGL" -DWITH_demos:BOOL=TRUE -DWITH_examples:BOOL=true -DWITH_tests:BOOL=TRUE -DCMAKE_CXX_FLAGS_RELEASE=-DCGAL_NDEBUG .. 
+- make 
+- cd .. 
+script: 
 - cd ./.travis
 - bash -x -e ./build_package.sh $PACKAGE
-compiler:
-  - clang
-  - gcc
-addons:
+addons: 
   apt:
     sources:
-      - sourceline: 'ppa:ppsspp/cmake'
+      - sourceline: 'ppa:ppsspp/cmake' 
+      - sourceline: 'ppa:hedges/qt5.5'
     packages:
       - clang-3.6
       - zsh
-      - cmake
-      - libboost1.55-dev
-      - libboost-system1.55-dev
-      - libboost-program-options1.55-dev
-      - libboost-thread1.55-dev
-      - libgmp-dev
-      - libmpfr-dev
-      - zlib1g-dev
-      - libeigen3-dev # too old
-      - qtbase5-dev
-      - qtscript5-dev
-      - libqt5svg5-dev
-      - qttools5-dev
-      - qttools5-dev-tools
-      - libqt5opengl5-dev
-      - libqt5gui5
-      - libqt5widgets5
-      - libqt5xml5
-      - qt5-qmake
-      # Not allowed (yet)
-      # - geomview
-      # - libglew1.5-dev
-      # - libipe-dev
-      # - libmpfi-dev
+      - cmake 
+      - libboost1.55-dev 
+      - libboost-system1.55-dev 
+      - libboost-program-options1.55-dev 
+      - libboost-thread1.55-dev 
+      - libgmp-dev 
+      - libmpfr-dev 
+      - zlib1g-dev 
+      - libeigen3-dev # too old 
+      - qt55base
+      - qt55script 
+      - qt55svg
+      - qt55tools
+      - qt55graphicaleffects
+       
+      - mesa-common-dev
+      - libglu1-mesa-dev
+      # Not allowed (yet) 
+      # - geomview 
+      # - libglew1.5-dev 
+      # - libipe-dev 
+      # - libmpfi-dev 
 notifications:
   email:
     on_success: change # default: always
diff --git a/.travis/packages.txt b/.travis/packages.txt
index b89307a1919..e30cdc33286 100644
--- a/.travis/packages.txt
+++ b/.travis/packages.txt
@@ -1,116 +1,116 @@
-AABB_tree
-Advancing_front_surface_reconstruction
-Algebraic_foundations
-Algebraic_kernel_d
-Algebraic_kernel_for_circles
-Algebraic_kernel_for_spheres
-Alpha_shapes_2
-Alpha_shapes_3
-Apollonius_graph_2
-Arithmetic_kernel
-Arrangement_on_surface_2
-Barycentric_coordinates_2
-BGL
-Boolean_set_operations_2
-Bounding_volumes
-Box_intersection_d
-CGAL_ImageIO
-CGAL_ipelets
-Circular_kernel_2
-Circular_kernel_3
-Circulator
-Combinatorial_map
-Cone_spanners_2
-Convex_decomposition_3
-Convex_hull_2
-Convex_hull_3
-Convex_hull_d
-Distance_2
-Distance_3
-Envelope_2
-Envelope_3
-Filtered_kernel
-Generalized_map
-Generator
-Geomview
-GraphicsView
-HalfedgeDS
-Hash_map
-Inscribed_areas
-Installation
-Interpolation
-Intersections_2
-Intersections_3
-Interval_skip_list
-Interval_support
-Inventor
-Jet_fitting_3
-Kernel_23
-Kernel_d
-Kinetic_data_structures
-Kinetic_framework
-Linear_cell_complex
-Matrix_search
-Mesh_2
-Mesh_3
-Minkowski_sum_2
-Minkowski_sum_3
-Modifier
-Modular_arithmetic
-Nef_2
-Nef_3
-Nef_S2
-NewKernel_d
-Number_types
-Optimal_transportation_reconstruction_2
-Partition_2
-Periodic_2_triangulation_2
-Periodic_3_triangulation_3
-Point_set_2
-Point_set_3
-Point_set_processing_3
-Point_set_shape_detection_3
-Poisson_surface_reconstruction_3
-Polygon
-Polygon_mesh_processing
-Polyhedron
-Polyhedron_IO
-Polyline_simplification_2
-Polynomial
-Polytope_distance_d
-Principal_component_analysis
-Profiling_tools
-QP_solver
-Random_numbers
-Ridges_3
-Scale_space_reconstruction_3
-Segment_Delaunay_graph_2
-Segment_Delaunay_graph_Linf_2
-Skin_surface_3
-Snap_rounding_2
-Solver_interface
-Spatial_searching
-Spatial_sorting
-STL_Extension
-Straight_skeleton_2
-Stream_lines_2
-Stream_support
-Subdivision_method_3
-Surface_mesh
-Surface_mesh_deformation
-Surface_mesher
-Surface_mesh_parameterization
-Surface_mesh_segmentation
-Surface_mesh_shortest_path
-Surface_mesh_simplification
-Surface_mesh_skeletonization
-Surface_sweep_2
-TDS_2
-TDS_3
-Three
-Triangulation
-Triangulation_2
-Triangulation_3
-Union_find
-Visibility_2
-Voronoi_diagram_2
+AABB_tree 
+Advancing_front_surface_reconstruction 
+Algebraic_foundations 
+Algebraic_kernel_d 
+Algebraic_kernel_for_circles 
+Algebraic_kernel_for_spheres 
+Alpha_shapes_2 
+Alpha_shapes_3 
+Apollonius_graph_2 
+Arithmetic_kernel 
+Arrangement_on_surface_2 
+Barycentric_coordinates_2 
+BGL 
+Boolean_set_operations_2 
+Bounding_volumes 
+Box_intersection_d 
+CGAL_ImageIO 
+CGAL_ipelets 
+Circular_kernel_2 
+Circular_kernel_3 
+Circulator 
+Combinatorial_map 
+Cone_spanners_2 
+Convex_decomposition_3 
+Convex_hull_2 
+Convex_hull_3 
+Convex_hull_d 
+Distance_2 
+Distance_3 
+Envelope_2 
+Envelope_3 
+Filtered_kernel 
+Generalized_map 
+Generator 
+Geomview 
+GraphicsView 
+HalfedgeDS 
+Hash_map 
+Inscribed_areas 
+Installation 
+Interpolation 
+Intersections_2 
+Intersections_3 
+Interval_skip_list 
+Interval_support 
+Inventor 
+Jet_fitting_3 
+Kernel_23 
+Kernel_d 
+Kinetic_data_structures 
+Kinetic_framework 
+Linear_cell_complex 
+Matrix_search 
+Mesh_2 
+Mesh_3 
+Minkowski_sum_2 
+Minkowski_sum_3 
+Modifier 
+Modular_arithmetic 
+Nef_2 
+Nef_3 
+Nef_S2 
+NewKernel_d 
+Number_types 
+Optimal_transportation_reconstruction_2 
+Partition_2 
+Periodic_2_triangulation_2 
+Periodic_3_triangulation_3 
+Point_set_2 
+Point_set_3 
+Point_set_processing_3 
+Point_set_shape_detection_3 
+Poisson_surface_reconstruction_3 
+Polygon 
+Polygon_mesh_processing 
+Polyhedron 
+Polyhedron_IO 
+Polyline_simplification_2 
+Polynomial 
+Polytope_distance_d 
+Principal_component_analysis 
+Profiling_tools 
+QP_solver 
+Random_numbers 
+Ridges_3 
+Scale_space_reconstruction_3 
+Segment_Delaunay_graph_2 
+Segment_Delaunay_graph_Linf_2 
+Skin_surface_3 
+Snap_rounding_2 
+Solver_interface 
+Spatial_searching 
+Spatial_sorting 
+STL_Extension 
+Straight_skeleton_2 
+Stream_lines_2 
+Stream_support 
+Subdivision_method_3 
+Surface_mesh 
+Surface_mesh_deformation 
+Surface_mesher 
+Surface_mesh_parameterization 
+Surface_mesh_segmentation 
+Surface_mesh_shortest_path 
+Surface_mesh_simplification 
+Surface_mesh_skeletonization 
+Surface_sweep_2 
+TDS_2 
+TDS_3 
+Three 
+Triangulation 
+Triangulation_2 
+Triangulation_3 
+Union_find 
+Visibility_2 
+Voronoi_diagram_2