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Instance variables

Listing 1 declares a number of instance variables. The purpose of these variables should become clear based on their names andtheir usage that I will discuss later.

The constructor and the main method

There is nothing new in the constructor and the main method in Listing 1 .

The init method

The init method begins in Listing 2 . The embedded comments should provide a sufficient explanation of the code in Listing 2 .

Listing 2 . Beginning of the init method.
public void init(GameContainer gc) throws SlickException {spriteSheetImage = new Image("Slick0180a1.png"); //Enlarge the sprite sheet.Image temp = spriteSheetImage.getScaledCopy(580,224); spriteSheetImage = temp;//Get, save, and display the width and the height // of the sprite sheet.spriteSheetWidth = spriteSheetImage.getWidth(); spriteSheetHeight = spriteSheetImage.getHeight();System.out.println( "spriteSheetWidth: " + spriteSheetWidth);System.out.println( "spriteSheetHeight: " + spriteSheetHeight);//Compute the width and height of the individual// sprite images. spriteWidth = (int)(spriteSheetWidth/spritesPerRow);spriteHeight = (int)(spriteSheetHeight/spritesPerColumn);

Create a SpriteSheet object

Listing 3 creates a new SpriteSheet object based on the sprite sheet image along with the width and height of the individual sprites.

Listing 3 . Create a SpriteSheet object.
//Instantiate a new Spritesheet object based on the // width and height of the tiles.spriteSheet = new SpriteSheet(spriteSheetImage, spriteWidth,spriteHeight);

Create a new Animation object

Listing 4 creates a new Animation object that will process the SpriteSheet object instantiated in Listing 3 .

Listing 4 . Create a new Animation object.
//Create a new animation based on a selection of // sprites from the sprite sheet.animation = new Animation(spriteSheet, 0,//first column0,//first row 4,//last column0,//last row true,//horizontalduration,//display time true//autoupdate);

Constructor parameters

Obviously, the first parameter to the constructor for the Animation class specifies the SpriteSheet object.

The second and third parameters specify that the first image in the sequence should be the top-left image in Figure 1 .

The fourth and fifth parameters specify that the last image in the sequence should be the top-right image in Figure 1 .

The true value for the sixth parameter specifies that the images should be scanned horizontally.

The duration value in the seventh parameter specifies that each image should be displayed for 200 milliseconds.

The true value for the last parameter specifies that the display should continue cycling through the images until the animation is stopped.

Set frame rate and display location

The code is Listing 5 sets the frame rate and specifies the drawing location. The drawing location is the locationwithin the game window where the sprite will be displayed.

Questions & Answers

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
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for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
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.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
how to synthesize TiO2 nanoparticles by chemical methods
how did you get the value of 2000N.What calculations are needed to arrive at it
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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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