Slides

TEST CASE 1: CGAL Hello World

• Download one (or several) of the source files
• In a directory containing the source file, run the following commands:
• /usr/local/bin/cgal_create_CMakeLists
• cmake -DCMAKE_BUILD_TYPE=Release .
• make
• then run the generated program

TEST CASE 2: Choosing a CGAL Kernel for Delaunay triangulations in 2D

• Download the source file choosing_kernel.cpp
• In a directory containing the source file, run the following commands:
• /usr/local/bin/cgal_create_CMakeLists
• cmake -DCMAKE_BUILD_TYPE=Debug .
• make
• ./choosing_kernel

• The program choosing_kernel stops with a message like:

  CGAL error: precondition violation!

  Expression : orientation(f->vertex(i)->point(), f->vertex(cw(i))->point(), mirror_vertex(f,i)->point()) == RIGHT_TURN && orientation(f->vertex(i)->point(), f->vertex(ccw(i))->point(), mirror_vertex(f,i)->point()) == LEFT_TURN

  Try to understand what went wrong using http://www.cgal.org/Manual/latest/doc_html/cgal_manual/TDS_2/Chapter_main.html

• Change the number type to the exact CGAL::MP_Float in the source file and recompile (make)
• Change the kernel to CGAL::Exact_predicates_inexact_constructions_kernel (EPIC)
• Compare the running times for points uniformly distributed in a square for EPIC kernel, CGAL::Cartesian kernel and CGAL::Cartesian kernel. Better use the "Release" mode for efficiency: cmake -DCMAKE_BUILD_TYPE=Release .

TEST CASE 3: Surface Reconstruction from Point Clouds

• Download CGAL examples
• Go to CGAL-5.3.1-examples-demos/examples/Poisson_surface_reconstruction_3
• cmake -DCMAKE_BUILD_TYPE=Release .
• make
• ./tutorial_example data/kitten.xyz
• Visualize the output file "out.ply" with your favorite viewer or online

TEST CASE 4: GIS: Geographic Information System

• Go to CGAL-5.3.1-examples-demos/examples/Classification
• cmake -DCMAKE_BUILD_TYPE=Release .
• make
• ./gis_tutorial_example data/b9.ply
• Visualize the output files with your favorite viewer or online