Programming and Graphics

176 Introduction to C++ Programming and Graphics

The implementation of the non-intrusivegetyfunction is:

double point::gety() const

{

return y;

}

The implementation of the mutatormovefunction is:

void point::move(double dx, double dy)

{

x = x+dx;

y = y+dy;

}

The main function is allowed to make any of the following calls:

• Define the default pointA, shift it, and print the original and new coor-
  dinates:

point A = point();

A.print();

A.move(-0.2, 0.4);

A.print();

• Define point B, shift it, and print the original and new coordinates:

point B = point(1, 2);

B.print();

B.move(0.3, 0.4);

B.print();

An alternative to the first statement is:

point B(1, 2);

• Print the coordinates of point (10, 15):

point(10, 15).print();

• Print the coordinates of the default point:

point().print();

• Setaequal to thexcoordinate of pointA:

doublea=A.getx();