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Listing 5 . Set frame rate and display location.
gc.setShowFPS(true);//show FPS ////set frame rategc.setTargetFrameRate((int)(1000/targetDelta)); //Set drawing location. This is the location within// the game window where the sprite will be displayed. spriteX = spriteWidth;spriteY = 0; }//end init

The update method

The update method is shown in Listing 6 . As indicated in the comments, the computation of totalTime in the method has nothing to do with the animation. Instead, it is used to display the clock timeas shown in Figure 2 .

Listing 6 . The update method.
public void update(GameContainer gc, int delta) throws SlickException{//Note that the following is for clock time display // only. It does not effect the animation.totalTime += delta;//update total time accumulator }//end update

The render method

The render method is shown in Listing 7 . The only thing that is new here is the call to the draw method on the Animation object.

Listing 7 . The render method.
public void render(GameContainer gc, Graphics g) throws SlickException{g.setDrawMode(g.MODE_NORMAL); g.setBackground(Color.gray);//Draw the currently selected animation image at the // specified locationanimation.draw(spriteX,spriteY); g.drawString("totalTime = "+totalTime/1000,10f,100f);}//end render }//end class Slick0180

Powerful behavior

The behavior of the Animation object and its draw method is very powerful.

  • The Animation object keeps track of the scheduling requirements of the animation, such as which image should be displayedat the current time.
  • Calling the draw method on the Animation object causes that image to actually be displayed.

The image display schedule being managed by the Animation object is independent of the frame rate.

The Animation object does its thing, and the render method does its thing virtually independent of one another. When the render method decides that it is time to display an animation image, it calls the draw method on the Animation object.

The Animation object delivers the image that is scheduled for display at that point in time according to the predetermined animationschedule and the draw method causes the image to be displayed.

Overloaded draw methods

There are several overloaded versions of the draw method including versions to filter the colors and to change the width and height ofthe displayed image.

Best results

Now you know why, as mentioned earlier , best results are achieved by keeping targetDelta less than the display time ( duration ) for each sprite. If targetDelta is greater than the duration , some images will be skipped and not displayed in the proper sequence.

For example, if the Animation object is switching from one image to the next every 0.10 second, but the draw method is only being called every 0.13 seconds, some of the images in the sequence won'tbe displayed and the quality of the animation will probably be poor.

However, this is also dependent on the amount of change from one image to the next. Ifthe change from one image to the next is small, then skipping an occasional image might not matter that much.

Questions & Answers

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
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
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?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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
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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