int Width = size().width;
int Height = size().height;
int width = Width/2;
int height = Height/2;
int x = (Width - width)/2;
int y = (Height- height)/2;
int [] polyx = { 0, Width/2, Width, Width/2 };
int [] polyy = { Height/2, 0, Height/2, Height };
Polygon poly = new Polygon( polyx, polyy, 4 );
g.setColor( Color.black );
g.fillRect( 0, 0, size().width, size().height );
g.setColor( Color.yellow );
g.fillPolygon( poly );
g.setColor( Color.red );
g.fillRect( x, y, width, height );
g.setColor( Color.green );
g.fillOval( x, y, width, height );
g.setColor( Color.blue );
int delta = 90;
g.fillArc( x, y, width, height, theta, delta );
g.setColor( Color.white );
g.drawLine( x, y, x+width, x+height );
