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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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
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
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
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.
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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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