Speed question

// with the following field declared in the world class
private InfoPanel info;
// in the constructor of that world class
TextImage.setDefaultName("Copperplate Gothic Bold");
TextImage.setDefaultSize(32);
String[][] data =
{
    { "New Game", "" },
    { "Setting", "Speed:  50\nWidth:  "+getWidth()+"\nHeight:  "+getHeight() },
    { "Controls", "Left:  move left\nRight:  move right\nSpace:  shoot" }
};
addObject(info = new InfoPanel(data), getWidth()/2, getHeight()/2);

import greenfoot.*;
import java.awt.Color;
import java.util.Arrays;

public class InfoPanel extends Actor
{
    private Actor[] buttons;

    /**
     * creates an InfoPanel object using the captions and texts given
     * 
     * param buttonData an array of paired Strings; captions and their displayed texts
     */
    public InfoPanel(String[][] buttonData)
    {
        buttons = new Actor[buttonData.length]; // initialize the button array
        for (int i=0; i<buttonData.length; i++) // for each button to add
        {
            buttons[i] = new Button(buttonData[i][0]); // assign new button with assigned caption to array
            ((Button)buttons[i]).setClickImage(createClickImage(buttonData[i][1])); // save the click image to button
        }
        setImage((GreenfootImage)null); // the infopanel will show click images when needed
    }
    
    /**
     * creates and returns the image with given text
     * 
     * param text the text for the image to display
     */
    private GreenfootImage createClickImage(String text)
    {
        GreenfootImage txtImg = new TextImage(text);
        GreenfootImage image = new GreenfootImage(txtImg.getWidth()+20, txtImg.getHeight()+20);
        image.setColor(new Color(93, 93, 93));
        image.fill();
        image.setColor(Color.lightGray);
        image.fillRect(5, 5, image.getWidth()-11, image.getHeight()-11);
        image.drawImage(txtImg, 10, 10);
        return image;
    }
    
    /**
     * adds the buttons into the world when the infopanel is placed into a world (or when clicked on -- see 'act' method)
     */
    protected void addedToWorld(World world)
    {
        for (int i=0; i<buttons.length; i++)
        {
            world.addObject(buttons[i], getX(), getY()+((i*2+1-buttons.length)*buttons[i].getImage().getHeight()/2));
        }
    }

    /**
     * returns to unclicked state when infopanel is clicked (button clicks go to clicked state)
     */
    public void act()
    {
        if (Greenfoot.mouseClicked(this))
        {
            setImage((GreenfootImage)null); // hides infopanel object
            addedToWorld(getWorld()); // adds buttons back into world
        }
    }            

    /**
     * returns the array of buttons for this infopanel
     */
    public Actor[] getButtons()
    {
        return buttons;
    }

    /** ********************************************************************************* */
    
    /**
     * The Button class creates clickable objects for an infopanel object
     */
    private class Button extends Actor
    {
        private GreenfootImage clickImage; // the image to set to the infopanel owner when button is clicked
        
        /**
         * creates the button with the given text
         */
        private Button(String text)
        {
            GreenfootImage txtImg = new TextImage(text);
            GreenfootImage image = new GreenfootImage(400, 120);
            image.setColor(new Color(93, 93, 93));
            image.fill();
            image.setColor(Color.lightGray);
            image.fillRect(25, 20, 349, 79);
            image.drawImage(txtImg, 200-txtImg.getWidth()/2, 60-txtImg.getHeight()/2);
            setImage(image);
        }

        /**
         * removes self if owner is removed from world;
         * sets image of owner and removes all owner buttons when clicked
         */
        public void act()
        {
            if (InfoPanel.this.getWorld() == null)
            {
                getWorld().removeObject(this);
                return;
            }
            if (Greenfoot.mouseClicked(this))
            {
                InfoPanel.this.setImage(clickImage);
                getWorld().removeObjects(Arrays.asList(buttons));
            }
        }
        
        /**
         * helper method to set the image to give owner when this button is clicked
         */
        public void setClickImage(GreenfootImage image)
        {
            clickImage = image;
        }
    }
}