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The big picture

Sifting through all of this detail in an attempt to get a big picture view, we see that we should:

  • Override Initialize for any special initialization and for loading any non-graphic resources. For example, sound files arenon-graphic resources.
  • Override LoadContent to load all graphic resources.
  • Override UnloadContent if any graphic resources need to be unloaded.
  • Override Update to implement all of the game logic.
  • Override Draw to draw an individual frame based on values created and stored by the overridden Update method, such as the current position of a sprite.
  • Be aware that there are two different approaches to controlling the timing of the game loop, depending on whether the IsFixedTimeStep property of the Game object is true or false. The default value is true, meaning that the game will attempt to callthe Update method on a fixed time interval even if that means that the Draw method doesn't get called during some iterations of the game loop.

The constructor for the Game1 class

Listing 5 shows the declaration of two instance variables followed by the constructor for the Game1 class. One of the instance variables is used in the constructor and the other is used later in theprogram.

Listing 5 . Constructor for the Game1 class.

GraphicsDeviceManager graphics; SpriteBatch spriteBatch;public Game1() { graphics = new GraphicsDeviceManager(this);Content.RootDirectory = "Content"; }// end constructor

What is a constructor?

A constructor is a special method-like structure that is executed once and only once during the instantiation of an object.

The first statement in the Main method in Listing 2 uses the new operator to cause the constructor to be executed. When the constructor completes its task, it returns a reference to theobject just constructed. That reference is stored in the local reference variable of type Game1 named game in Listing 2 .

A new GraphicsDeviceManager object

The first statement in the constructor in Listing 5 instantiates a new object of the class GraphicsDeviceManager and stores that object's reference in the instance variable named graphics .

The documentation for GraphicsDeviceManager isn't very descriptive. Here is some of what Aaron Reed (the author of the Learning XNA books from O'Reilly) has to say on the topic.

"This (GraphicsDeviceManager) is a very important object because it provides you, as a developer, with a way to access the graphics device on your ... The GraphicsDeviceManager object has a property calledGraphicsDevice that represents the actual graphics device on your machine."

He goes on to explain how the GraphicsDevice object acts as a conduit between your XNA program and the physical graphics device on yourmachine.

Passing the this keyword as a parameter

Note the parameter that is passed to the GraphicsDeviceManager constructor in Listing 5 . The documentation tells us that the parameter must be of type Game and is the Game that the GraphicsDeviceManager should be associated with.

I don't recall having discussed the keyword this earlier in this collection of modules. According to Jesse Liberty ( Programming C# from O'Reilly)

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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