CS274 Computational Geometry

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This week, I worked on compiling and running some example programs as I followed the "Getting Started with CGAL" document, Chapter 2. As I ran and compiled the programs, if possible I created Cinderella drawings of what was happening in the programs.

Example file: examples/Getting_started/basic.C (I don't have the link ready yet, but it will be here soon)

When we compile and run the program*, the output is:

 Vector v2 has coordinates: (3, 4)

Point p3 has coordinates: (8, 31)

  (* To compile I needed to modify the makefile and just type "make basic"

• This Cinderella applet shows the variables, the two points and the two vectors. Although, I couldn't find a way to put arrows on the lines to show the directions of the vectors, following the code, it is easy to figure out.
• This one shows the final outcome of the program. Point p3 is the endpoint of the long black line. And vector v2 is shown at its original position. Note that to be able to see the value (3, 4) on the vector you need to place the endpoint of it on the origin.

1. Include files -

First include file is "tutorial.h". It contains some definitions that make the example programs easier to read.Then, there are the header files that define CGAL points and vectors.Then, there is the I/O file, since the program outputs results.

** Order is really important. "tutorial.h" has to go first.

2. Variable declarations -

There are 3 2D points. The first two are initialized whereas the thrid one isn't. There are 2 vectors. The first one is initialized the same way as the points. The third one is initialized as a difference of two points.

3. Operations -