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Figures in the middle group

The process of computing the horizontal position coordinate value continues in Listing 8 .

Listing 8 . Don't change position for middle group of sprite images.
}else if(frame<2*oneThird){ //Sprite is stationary. Don't change position

Listing 8 tests to determine if the current frame is in the middle group. If so, it causes the update method to return without changing the horizontal position coordinate value,thus allowing the sprite to remain in a stationary position.

Figures in the third group

The horizontal position values computed in Listing 9 make it appear that the sprite is running from right to left across the gamewindow.

This is one of those opportune times when it is appropriate to say that I will leave it as an exercise for the student to dust off their high-schoolalgebra books and figure out how the code in Listing 9 achieves the desired result.

Listing 9 . Run from right to left.
}else if(frame<3*oneThird){ //Cause the sprite to turn around and start// moving to the left toward the starting point. //Reduce frame count by number of frames during// which the sprite wasn't moving. frame -= oneThird;//Compute the new position. spriteX = (2*oneThird - frame)*stepSize;}//end else if}//end update

Listing 9 also signals the end of the update method.

The render method

Now it's time to realize the benefit of all of the hard work that went into planning for and writing the code in the init and update methods. The code in the render method, which is shown in Listing 10 , is almost trivial.

Listing 10 . The render method.
public void render(GameContainer gc, Graphics g) throws SlickException{g.setDrawMode(g.MODE_NORMAL); g.setBackground(Color.gray);animation.draw(spriteX,spriteY); }//end render}//end class Slick0190

There is nothing left for the render method to do other than to send a message to the Animation object once during each iteration of the game loop asking it to draw the current frame.

Listing 10 signals the end of the render method, the end of the Slick0190 class, and the end of the program.

Run the program

I encourage you to copy the code from Listing 11 . 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 objects of the SpriteSheet class and the Animation class to perform more complex sprite sheet animations than was the case in the previous module.

What's next?

In the next module, you will learn how to develop a sprite class from which you can instantiate and animate swarms of sprite objects.


This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Slick0190-Sprite sheet animation, part 2
  • File: Slick0190.htm
  • Published: 02/06/13
  • 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.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
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
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.
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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