Projectiles - Physics for Game Programmers - page 118

The actionPerformed method that is called when the Fire button is pressed extracts the
input values from all of the text fields including the input values for the x- and y-components
of wind velocity. A WindProjectile object is created and initialized with the input values. The
start method is called to begin the simulation.
// The actionPerformed() method is called when
// the Fire button is pressed.
public void actionPerformed(ActionEvent event) {
// Get the initial quantities from the text fields.
double vx0 = Double.parseDouble(vxTextField.getText());
double vy0 = Double.parseDouble(vyTextField.getText());
double vz0 = Double.parseDouble(vzTextField.getText());
double mass = Double.parseDouble(massTextField.getText());
double area = Double.parseDouble(areaTextField.getText());
double cd = Double.parseDouble(cdTextField.getText());
double density = Double.parseDouble(densityTextField.getText());
distanceToHole = Double.parseDouble(distanceTextField.getText());
double windVx = Double.parseDouble(windVxTextField.getText());
double windVy = Double.parseDouble(windVyTextField.getText());
// Create a WindProjectile object representing the golf ball.
golfball = new WindProjectile(0.0, 0.0, 0.0, vx0, vy0, vz0,
0.0, mass, area, density, cd, windVx, windVy);
// Update the display.
updateDisplay();
// Start the box sliding using a Timer object
// to slow down the action.
gameTimer.start();
}
The actionPerformed method that the Timer object calls in the GolfGame3 class is exactly
the same as the actionPerformed method that the Timer called in the GolfGame2 class (which
was exactly the same as the actionPerformed method in the GolfGame class).