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The Input class also provides two methods named getAbsoluteMouseX and getAbsoluteMouseY . I'm not certain how these two methods differ from the two methods that were calledin Listing 4 , but I haven't spent any time investigating the difference.

The end of the update method

Listing 4 also signals the end of the update method and the end of this discussion.

Run the program

I encourage you to copy the code from Listing 5 . Compile the code and execute it,making changes, and observing the results of your changes. Make certain that you can explain why your changes behave as they do.


In this module, you learned how to use the following methods of the Input class to get user input:

  • isKeyDown
  • isMouseButtonDown
  • getMouseX
  • getMouseY

What's next?

In the next module, you will learn how to use objects of the SpriteSheet class and the Animation class to perform simple sprite sheet animation.


This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Slick0170: Mouse and keyboard input
  • File: Slick0170.htm
  • Published: 02/05/13
  • Revised: 09/03/15

Financial : Although the Connexions site makes it possible for you to download a PDF file for thismodule at no charge, and also makes it possible for you to purchase a pre-printed version of the PDF file, you should beaware that some of the HTML elements in this module may not translate well into PDF.

I also want you to know that, I receive no financial compensation from the Connexions website even if you purchase the PDF version of the module.

In the past, unknown individuals have copied my modules from cnx.org, converted them to Kindle books, and placed them for sale on Amazon.com showing me as the author. Ineither receive compensation for those sales nor do I know who does receive compensation. If you purchase such a book, please beaware that it is a copy of a module that is freely available on cnx.org and that it was made and published withoutmy prior knowledge.

Affiliation : I am a professor of Computer Information Technology at Austin Community College in Austin, TX.

Complete program listing

A complete listing of the program discussed in this module is provided in Listing 5 .

Listing 5 . Source code for the program named Slick0170.
/*Slick0170java Copyright 2013, R.G.BaldwinCause a ladybug sprite to move inside the game window by pressing the arrow keys or the left and right mousebuttons. The mouse pointer must be inside the game window for the mouse buttons to move the sprite.Right arrow or right mouse button: move right Left arrow or left mouse button: move leftUp arrow: move up Down arrow: move downThe program also gets and displays the X and Y coordinates of the mouse pointer.Much of this program is identical to the earlier program named Slick0150a.java.Tested using JDK 1.7 under WinXP *********************************************************/import org.newdawn.slick.AppGameContainer; import org.newdawn.slick.BasicGame;import org.newdawn.slick.GameContainer; import org.newdawn.slick.Graphics;import org.newdawn.slick.Image; import org.newdawn.slick.SlickException;import org.newdawn.slick.Input; public class Slick0170 extends BasicGame{Image bug = null;Image background = null;float backgroundWidth; float backgroundHeight;float bugX = 100;float bugY = 100; float bugWidth;float bugHeight;float xStep = 4.0f;//horizontal step size float yStep = 3.0f;//vertical step sizefloat bugScale = 0.75f;//drawing scale factor//Frame rate we would like to see and maximum frame// rate we will allow. int targetFPS = 60;//This is new code relative to Slick0150a.javaint mouseX = 0; int mouseY = 0;//----------------------------------------------------// public Slick0170(){//constructor//Set the title super("Slick0170, baldwin");}//end constructor //----------------------------------------------------//public static void main(String[] args)throws SlickException{ AppGameContainer app = new AppGameContainer(new Slick0170(),414,307,false); app.start();}//end main //----------------------------------------------------//@Override public void init(GameContainer gc)throws SlickException { bug = new Image("ladybug.png");background = new Image("background.jpg");backgroundWidth = background.getWidth(); backgroundHeight = background.getHeight();bugWidth = bug.getWidth()*bugScale;bugHeight = bug.getHeight()*bugScale;System.out.println( "backgroundWidth: " + backgroundWidth);System.out.println( "backgroundHeight: " + backgroundHeight);System.out.println("bugWidth: " + bugWidth); System.out.println("bugHeight: " + bugHeight);gc.setTargetFrameRate(targetFPS);//set frame rate}//end init //----------------------------------------------------//@Override public void update(GameContainer gc, int delta)throws SlickException{ //Most of the code in this method is different from// the code in Slick0150a.java.//Get a reference to the Input object. Input input = gc.getInput();//Control horizontal bug position by pressing the// arrow keys or pressing the left and right mouse // buttons.if(input.isKeyDown(Input.KEY_RIGHT) || input.isMouseButtonDown(Input.MOUSE_RIGHT_BUTTON)){bugX += xStep; }//end ifif(input.isKeyDown(Input.KEY_LEFT) ||input.isMouseButtonDown(Input.MOUSE_LEFT_BUTTON)){ bugX -= xStep;}//end if//Control vertical bug position by pressing the arrow // keys. Vertical bug position cannot be controlled by// pressing mouse buttons. if(input.isKeyDown(Input.KEY_UP)){bugY -= yStep; }//end ifif(input.isKeyDown(Input.KEY_DOWN)){bugY += yStep; }//end if//Test for collisions with the sides of the game// window and stop moving the bug when a collision // occurs.if(bugX + bugWidth>= backgroundWidth){ //Set the position to the right edge less the width// of the sprite. bugX = backgroundWidth - bugWidth;}//end if//Continue testing for collisions with the edges. if(bugX<= 0){ bugX = 0;}//end ifif(bugY + bugHeight>= backgroundHeight){ bugY = backgroundHeight - bugHeight;}//end ifif(bugY<= 0){ bugY = 0;}//end if//Get and save the X and Y coordinates of the mouse // pointer.mouseX = input.getMouseX(); mouseY = input.getMouseY();}//end update//----------------------------------------------------// public void render(GameContainer gc, Graphics g)throws SlickException{ //set the drawing mode to honor transparent pixelsg.setDrawMode(g.MODE_NORMAL);//Draw the background to erase the previous picture. background.draw(0,0);//Draw the bug in its new location.bug.draw(bugX,bugY,bugScale);//Display the location of the mouse pointer. This is // new code relative to Slick0150a.javag.drawString( "X: " + mouseX + " Y: " + mouseY,100f,10f);}//end render }//end class Slick0170//======================================================//


Questions & Answers

what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Anatomy of a game engine. OpenStax CNX. Feb 07, 2013 Download for free at https://legacy.cnx.org/content/col11489/1.13
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