Changes in the name used for the game map canvas area, instead of 'viewport' now is named 'canvas'.. game canvas.
Now the box over the map are properly drawn, also the calculation for the field when the user press down a button was fixed.
Some changes in the city map draw procedure, i removed the many get_vertex function call. now citymap_graphic_t is responsible for drawing the city map ( draw_the_map( sf::RenderWindow& window ) ). The second changes is in the node_t, now the graphic information are stored in the field_graphic_info structure (vertex and texture)
Now when a construction is built on a field the color of the field is changed to blue. Also a 'stop' function was introduced to clean all the resource just before killing the application
Small changes in the startup procedure. (check  the amount of buildings)
Small fix in read_building_file
Small fix in handle_new_construction